Proceedings of the 23Rd Forum on the Geology of Industrial Minerals, May

14.GS: -^Ssfefc^ IMN 102 c. 1

Proceedings of the 23rd Forum on the Geology of Industrial Minerals

Randall E. Hughes and James C. Bradbury, editors

Sponsored by the Department of Energy and Natural Resources ILLINOIS STATE GEOLOGICAL SURVEY May 11-15, 1987 North Aurora, Illinois

December, 1989 1987 LOCAL COMMITTEES

J. W. Baxter; general chairman

J. C. Bradbury and R. E. Hughes; technical program co-chairman

H. P. Ehrlinger, HI, J. H. Goodwin, J. M. Masters, and W. A. White; organization J. W. Baxter, J. H. Goodwin, R. E. Hughes, J. M. Masters, D. G. Mikulic, and W. A. White; field trip leaders

1987 FORUM STEERING COMMITTEE

Norman F. Williams, past chairman, 1986 James W. Baxter, chairman, 1987 David A. Hopkins, 1987 Robert W Powers, 1988 Charles T. Steuart, 1989

FUTURE HOSTS Alan-Jon W Zupan, 1988 Ronald P. Geitgey, 1989 Palmer C. Sweet, 1990

ANNUAL MEETING OF THE FORUM ON THE GEOLOGY OF INDUSTRIAL MINERALS 1965 Columbus, Ohio 1966 Bloomington, Indiana 1967 Lawrence, Kansas 1968 Austin, Texas 1969 Harrisburg, Pennsylvania 1970 Ann Arbor, Michigan 1971 Tampa, Florida 1972 Iowa City, Iowa 1973 Paducah, Kentucky 1974 Columbus, Ohio 1975 Kalispell, Montana 1976 Atlanta, Georgia 1977 Norman, Oklahoma 1978 Albany, New York 1979 Golden, Colorado 1980 St. Louis, Missouri 1981 Albuquerque, New Mexico 1982 Bloomington, Indiana 1983 Toronto, Ontario, Canada 1984 Baltimore, Maryland 1985 Tuscon, Arizona 1986 Litde Rock, Arkansas 1987 North Aurora, Illinois 1988 Greenville, South Carolina 1989 Portland, Oregon 1990 Charlottesville, Virginia

Cover photo: State-of-the-art mining at the Ottowa Silica Company Quarry in July 1940. Workers used scrapers to remove thin overburden down to the sandstone, then shoveled out (by hand) the loose overburden remaining in depressions and loaded it onto this brand-new dump-truck. The final cleaning was done with stiff brushes and compressed air or steam. The men (left center) are drilling a blast-hole on the cleaned sandstone surface; in the background is the processing plant.

Graphics: Pamella Foster Layout and Design: Pamella Foster andDebra Coffman

Printed by authority of the State ofIllinois/1989/700. Proceedings of the 23rd Forum on the Geology of Industrial Minerals

Randall E. Hughes and James C. Bradbury, editors

May 11-15, 1987 North Aurora, Illinois

ILLINOIS STATE GEOLOGICAL SURVEY Morris W. Leighton, Chief

Natural Resources Building 615 East Peabody Drive Champaign, IL 61820 FORUM DEDICATION

Dr. Ralph E. Grim, the keynote author in this proceedings, died August 19, 1989, shortly after returning from a consulting trip. Because of his lifelong interest in industrial minerals and the help and guidance he gave to many of us, we dedicate this volume to Dr. Grim's memory. Contents

Keynote address: Industrial Minerals Research 1 Ralph Grim

The Current State of Industrial Minerals in China 5 Fred Barnard

Geology of Six Kentucky Carbonates: Sulfur Sorbents for AFBC H Lance S. Barron, Garland R. Dever, Jr., and Thomas L. Robl

Possible Underground Mining of Limestone and Dolomite in Central Illinois 21 James W. Baxter

Model of Contruction Aggregates Demand and Supply: A Chicago Area Case Study 29 Subhash B. Bhagwat

Industrial Sand in Indiana 35 Donald D. Carr, Curtis H. Ault, and Todd A. Thompson

Depositional Environments of Natural-Aggregate Reserves, Osseo District, Twin Cities Metropolitian Area, Minnesota 41 Rudolph K. Hoagberg

Evaluation of the Economic Usefulness of Earth Materials by X-Ray Diffraction 47 Randall E. Hughes and Robin L. Warren

The History, Geology, and Future of Industrial Clays in Illinois 59 Randall E. Hughes, W. Arthur White, and Robin L. Warren

Effects of Rock Types in Illinois Gravels on Freeze-Thaw Test Beams 71 John M. Masters

The Chicago Stone Industry: A Historical Perspective 83 Donald G. Mikulic

An Overview of the Geology of Clays, Shales, and Slates Utilized in Ceramic and Structural Clay Products in Georgia 91 Bruce J. O'Connor

Industrial Minerals and the CUSMAP Program 97 A. W Rueff

Silica Sands: Grassroots Exploration or Acquisitions 101 Mark J. Zdunczyk

Enhancement of Sulfur Dioxide Sorption Reactivity of Limestone (abstract) 105 Massoud Rostam-Abadi, D. L. Moran, R. R. Frost, R. D. Harvey, and G. C. Sresty

Reserve Evaluation and Planning on an IBM Personal Computer (abstract) 105 George F. Swindle Digitized by the Internet Archive

in 2012 with funding from

University of Illinois Urbana-Champaign

http://archive.org/details/proceedingsof23r102foru Keynote Address: Industrial Minerals Research

Ralph Grim, Professor Emeritus Department of Geology University ofIllinois Urbana, Illinois 61801

Development of bentonites Our keynote speaker, Ralph Grim, is a father of clay mineralogy. His career The development of bentonites in this has been marked with outstanding scientific achievements and service to the State country was primarily the result of the ef- ofIllinois, the University ofIllinois, and the national and international scientific forts of two men. In the 1920s and 1930s and industrial communities. Dr. Grim earned his bachelor's degree from Yale George Radcliffe, head of the Baroid University and his doctoratefrom the University ofIowa. He began his career in Corporation (now part of the NL Indus- geology more than 60 years ago as Assistant Professor at the University Mis- of tries), realized, with the development of sissippi when he was also Assistant State Geologist of Mississippi. Dr. Grim rotary drilling for oil in the Gulf Coast joined the Illinois State Geology Survey (ISGS) in 1931 as a petrographer and region, that drilling muds were essential became widely knownfor his work on clays and clay minerals. He became Prin- in that process. He also realized that ben- cipal Geologist of the ISGS in 1945, and from 1948 to 1967 was a research tonites could produce superb drilling professor ofgeology at the University ofIllinois. Dr. Grim has been widely recog- fluids, and he developed that business. nized. Among his honors are the Gold Medal and honorary membership in the Bentonites set into a gel when drilling is Clay Minerals Society of Spain in 1972; the Medal of the National Order and stopped and tend to hold cuttings in designation as a Chevalier of the National Order of the Republic the Ivory of suspension so they do not drop to the bot- Coast in 1973; the prestigious Roebling Medal of the Mineralogical Society of tom and freeze the drill stem. Bentonites America in 1974, the highest honor that can be bestowed by that society in his also tend to produce an impervious wall field; and in 1984, an honorary doctoral degree from the University Illinois. of on the inside of the drillhole. He continues to be active in scientific circles, and has published more than 120 Much research has since been done on articles and three books. Dr. Grim doesn't know this, but many his books were of the use of bentonites in drilling fluids. my primers when I began my research work in the X-ray diffraction laboratory One interesting problem is that when you the of Carter Oil Research Company in Tulsa, Oklahoma. His life has touched drill a well through clays and shales you many of us in many waysfor many years. unavoidably grind up a lot of that clay and shale and add it to the mud. The mud be- Morris W. Leighton, Chief comes increasingly viscous—so viscous Illinois State Geological Survey that it has to be modified. Obviously, you could dilute the mud with water to reduce the viscosity, but this would reduce the INTRODUCTION in the Gulf Coast areas of Texas, Missis- weight of the mud, which is not desirable. Many industrial minerals such as sippi, and Alabama and in the Rocky Research has been conducted on how to sands and gravels require very little Mountain states. The development of the control the viscosity of the mud. Various preparation before they are used commer- bentonite industry is an American event. chemicals, particularly certain phos- cially. Some require a moderate amount Bentonite was recognized and developed phates, have proven valuable for this pur- of preparation—perhaps grinding, perfor industrial use here years before pose. haps a little purification, perhaps clas- Europeans and others even realized that Paul Bechner, head of the American sification. Others profit from substantial it existed. In England, bentonite was Colloid Company in Chicago for many preparation before they are put on the produced as fuller's earth for many years; years, also helped to develop the ben- market or used, and still others are the raw however, it was the Americans who tonite industry. During the 1920s and materials for a variety of manufacturing recognized the equivalence of bentonite 1930s, when foundries become mech- processes. This paper is concerned with and fuller's earth. anized and shifted over to synthetic mold- research to improve methods of preparing Bentonite has unique properties: it ing sands, he appreciated the possibility industrial minerals for use and to extend swells in water, produces gel-type struc- of using bentonite as a bonding agent for and improve products made from them. tures, and has high adsorptive capacity. It synthetic molding sands. can adsorb various organic and inorganic Properties and uses of bentonites BENTONITE ions that are commonly replaceable one Bentonite is a peculiar One of die factors that causes variation kind of clay for another. It is exceedingly plastic. The composed entirely of in the properties of bentonite from place montmorillonite, a properties of bentonite obtained from dif- to place is the particular member of the smectite group of clay ferent places can vary widely. cation that is ad- minerals. In the United States, bentonite sorbed by the bentonite. A bentonite that is produced mostly in Wyoming but also is carrying sodium will have somewhat different properties from a bentonite car- petroleum industry from kaolinite, and The use of bentonites in the disposal rying calcium. The properties preferred recently an excellent catalyst was made of high-level radioactive wastes is a cur- for drilling and bonding clays are com- by a totally different process in which rent interest of mine and many others as monly developed in the sodium ben- dehydroxylated kaolin is treated with well. High-level radioactive wastes and tonites rather than in the calcium caustic soda to create a zeolite-type struc- some other materials can probably be dis- bentonites. Bentonite producers ture having superb catalytic properties. posed of by calcining the waste material worldwide add soda ash to bentonites to This process results in a gasoline with an with a flux to form a slag in which the hot change their characteristics and control exceedingly high octane number. isotopes are locked up in a relatively in- their properties. A good deal of research Reactions with organics In the early soluble form. The slag is placed in con- has gone into developing ways to add 1940s there was a furious effort on the duits or pipes about a foot in diameter and soda ash to get maximum improvement. part of the Army Air Corps to find some about 10 feet long. These pipes are then

Some bentonites decolorize oil and way to quickly solidify soil, so that if its carried to an underground facility, where thus can be used as fuller's earth—as is men captured a Pacific island they could holes are drilled to a diameter of about 30 one of the English bentonites. By treating go in and harden the soil quickly in order inches. The pipes are lowered into the certain bentonites with acids you can en- to land planes on it. This research in- holes and completely surrounded by ben- hance the decolorizing property and you volved some work with organic materials tonite, with bentonite beneath them and can manipulate this process, by varying and soil, much of which was done at the bentonite on top of them. The bentonite time, temperature, and acid concentra- Massachusetts Institute of Technology forms an impervious seal around the tions, to produce adsorbents that are (MIT) by Ernest Hauser. pipes; also, it will adsorb the isotopes in specific for a particular kind of oil (cot- About 1942, George Radcliffe set up the event that the pipes should be rusted tonseed oil, for instance). a fellowship at Mellon Institute to inves- through or broken, preventing the iso- Catalytic properties In some cases, tigate other potential uses of bentonite. topes from escaping into the groundwater bentonites have catalytic properties—the He chose a group of people to select the system. ability to change the character of organic topic of research and advise the fellow. Bentonite probably will not be used in molecules because of their reaction with The research topic this group selected its pure form in such an operation but will the montmorillonite surface. The process was the reaction of bentonite with various be mixed with zeolites, another type of for producing gasoline by refining crude organic compounds. Soil chemists, ag- mineral with high capacity for fixation of oil changed around the 1920s from distil- ronomists, and others were particularly isotopes. Some ceramic research labora- lation processes to the use of catalysts. interested in the reaction of organics in tories have recently developed synthetic The early catalysts used in the petroleum soils with clay materials. materials that have a very high potency industry were synthetic granular ma- The fellow chosen, John W. "Spike" for the adsorption and fixation of atomic terials (a little coarser than sugar or small Jordan, was a bright, young organic wastes. These would also be added to the pellets) such as silica compounds with chemist. He went to work at Mellon and bentonite, probably to form about a 50:50 magnesium.When the catalysts are mixed in about three or four years came up with mixture; the bentonites would form an with the feed stock and heated to a what now are known as "bentones." Ben- impervious seal and the other materials temperature of a couple of hundred tones are organically treated bentonites in added would aid in trapping any isotopes degrees centigrade, they break down the which the individual layer components of that might escape. feed stock into gasolines and into carbon the montmorillonite are coated with a thin The Swedish government is currently that is coated on the catalysts. sheet of organic molecules. The character using this method of disposal of atomic

A successful catalyst must be hard. It of the bentonite is thus changed; instead waste on a pilot-plant scale. Sweden is in- must be able to convert a high percentage of being water absorbent, it becomes tensely interested in atomic energy be- of the feed stock to gasoline, and the water repellent and adsorbs and gels cause it has no coal or oil and has used all gasoline formed must have an acceptable many organic liquids. Now produced of its potential sites for hydroelectric octane number. A great deal of research commercially, bentones are used in energy. Except for atomic energy, has been done on developing catalysts for preparing lubricating greases (in place of Sweden has few energy sources for the petroleum industry that can achieve soaps) and in many other ways. The work making electricity. The Swedes are now these desired results. by Spike Jordan opened the door for re- investigating the use of bentonites in In the 1940s, around the time of World search into the reaction of all sorts of or- radioactive waste disposal in an aban- War II, Wright Gary, who was head of the ganic materials with all of the various doned iron mine located within a mass of

Filtrol Corporation in Los Angeles, con- types of clay minerals. granite at a depth of about 1 500 feet. This ceived of the idea that bentonites might Bentonite sealers Bentonite has the activity is sponsored not only by the be used to make a satisfactory catalyst for power of fixing many organic and inor- Swedish government, but by our own

producing aviation gasoline. After about ganic materials; it also can form a very government as well. I have been in the two years of research, he succeeded in impervious seal. For example, if you mine, and it is quite a place. One of the producing the first satisfactory catalyst spread a little bentonite along a drainage largest computers you could imagine is in from clay material. ditch it becomes impervious to water. I the mine, 1500 feet underground. The Since that time, catalysts for the have prevented water from leaking into laboratory work for the procedure of

petroleum industry have been produced our house by spreading a layer of benton- atomic waste disposal is being done at by treating other clay minerals. Plants in ite all around die outside wall. Luleo, just south of the Arctic Circle, at a Georgia are producing catalysts for the —

branch of the University of Sweden and very smooth surface is required for ac- altered volcanic ashes; this poses the in- the Swedish Geological Survey. ceptable printing. The Cretaceous kaolins teresting problem of why the volcanic ash are excellent for this. The preparation of is altered to a zeolite rather than to smec- KAOLINS the coating-grade product involves tite, a clay. The zeolites have a structure Kaolins are clays composed essential- delaminating the kaolins— that is, they completely different from that of the ly of the clay mineral kaolinite. They are are split on their cleavages during the clays. The silica tetrahedral units are tied used in the manufacture of various grinding process. A vast amount of re- together in a netlike structure that ceramic products, refractories, china- search has gone into making big flakes provides tremendous adsorption capa- ware, sanitaryware, and also paper used from tiny flakes in the Tertiary kaolins so city. Some of the silicon is replaced by as fillers and coating agents. It comes as that these kaolins might also be used to aluminum, which gives the zeolites a high a real surprise to many people to learn that make a satisfactory surface for book and cation exchange capacity. The zeolites a sheet of paper like that in used Nation- rotogravure printing. Considerable suc- have been used as molecular sieves to al Geographic is more than half clay. cess has been obtained by tacking these classify various materials. Zeolites can be In Georgia, many deposits of kaolin flakes together with an organic, some- made commercially, but, as I said, in are found in an area stretching from near times using a big flake to act as a kind of recent years huge deposits of zeolites Macon on the southwest to about the core to hold the tiny flakes together. have been found. South Carolina line on the northeast. There is far more to research on Last year, in extreme western Idaho They are lenticular masses, 15 feet thick preparing clay for the paper industry than and extreme eastern Oregon, I spent some or more, composed essentially of pure just removing the little bit of grit present time looking at these zeolites.There's one kaolinite and commonly found in sand- in the kaolin. The goal of such research is deposit up there in which they put a stone. Georgia kaolinite is unique world- to prepare a material that produces a drillhole down through about a hundred wide in that it contains no fine quartz printable surface with acceptable gloss feet of solid clinoptilolite zeolite, and if particles— grit no that cannot be easily a sheet of paper that is very, very thin, yet you look at a thin section of this material removed. Therein lies its special value. opaque enough so that advertisers can't under the microscope you can still Hundreds see the of thousands of tons of kaolin see a competitor's message through the structure of the parent ash. This zeolite are exported every year from the deposits sheet of paper they are reading. clearly is altered volcanic ash. in Georgia to Germany, Japan, Brazil, and One small area in Georgia contains Zeolites have interesting adsorption elsewhere because of its unique charac- some kaolins with smectite, a component properties, as I mentioned earlier. They teristics. It costs too much to produce a in bentonites. How this came about, I also have the ability to fix various completely grit-free kaolin from deposits don't know the origin of — the Tertiary isotopes, so it's possible that a natural or in many other parts of the world, and kaolins is also a mystery to me. I can't un- synthetic zeolite will be used paper as an in- manufacturers won 't have anything derstand how such extremely fine gredient in material used to form the seal to do with a clay that's at all gritty. If you material could have been transported a around the atomic waste run containers. an X-ray diffraction pattern on a sizable distance from any source area Zeolites have other properties, and sample of kaolin and there's even the very without somewhere along the line hav- there's considerable research going on at slightest indication that quartz is in it, that ing picked up some grit that had been the present time to discover potential uses kaolin isn't any good for the paper in- washed into the stream —so that grit was for them. Zeolites are granular. They dustry. The grit tends to wear out the deposited with the very fine kaolin. Now, don't tend to mix with water, so they fourdrinier wire in the paper-making the origin of the Cretaceous kaolins is won't form a mud. They tend to fix potas- machines. It also tends to produce an reasonably clear: they were transported sium and various organic compounds, abrasive so surface on the sheet of paper, only a very, very short distance from they've been loaded with nitrogenous which tends to wear out the type face of saprolites in the Piedmont, where altera- materials and potash and used to provide the offset printing masters. tions produced a material composed of the plant food for plants growing in a tank Two varieties of kaolins are found in extremely large crystals of kaolinite and of water. (Instead of putting your Georgia. In kaolins of Cretaceous age, the only large particles of quartz. nutrients in solution into the tank, you ad- kaolinite is present in sizable vermicules sorb them in the zeolites.) The zeolites or "books" in crystals that you can some- ZEOLITES slowly release the nutrients to the plants times see with a hand lens. The other In recent years, there has been a great over a period of time. When the zeolites kaolins, of Tertiary age, are completely deal of interest in another type of in- are exhausted, you take them out, different. They are composed of extreme- dustrial mineral that nobody had ever replenish them, and use them again. ly thin, small flakes about a micrometer paid much attention to—the zeolites. In Zeolites also can absorb a variety of or so in size odors that are packed together, one my days at the university, zeolites were a and have been used as deodorants. on top of the other, in a kind of random mineral curiosity. They occurred in very A man who lives near the fashion. They break Idaho down only to ag- small amounts, sometimes in vugs in ig- deposit has taken upon himself the gregates, not job of to individual flakes. neous rocks, but they were not particular- finding uses for these zeolites. He recent- Material used for coating paper should ly abundant and nobody considered that ly set up some research projects in the contain some relatively large flakes to they might have commercial use. local high school in which a group of stu- heal the openings in the fiber that makes Recently, however, tremendous deposits dents investigated the up the potential uses of base of the paper. For some types of zeolites have been found in our zeolites. One bright young woman got of printing (rotogravure, for example) a western states. Some of these zeolites are hold of some soil that contained a good —

deal of phosphate, but the phosphorous tle or no technical background. Conse- area. They changed the flow of water was locked up in a calcium compound quently, they are reluctant to be frank through bedrock material, and probably and was not readily available to the about their problems, and you don't have there was bentonite somewhere in these plants. So she mixed some zeolite with a chance to contribute anything. I know Cretaceous formations. (Cretaceous for- this particular soil and planted radishes of a couple of cases in which a company mations are notorious for the presence of and alfalfa in test plots. She reported that I was supposed to be a consultant for pur- bentonite and smectite types of ma- the zeolites tended to release the phos- chased deposits that I happened to know terials.) Analysis showed that there was phate and that she got increased yields of about. They lost a good deal of money at- about 10 to 15 percent smectite in the radishes and alfalfa when the zeolites tempting to develop these materials for materials at the site. So what do you do were added. Zeolites are an interesting which there was no hope. I didn't know about it? In the first place, you make sure resource with a promising future. about their plans to purchase the deposits that you keep all the water away from the or their efforts to develop them, and in the formation; there are also ways that a GYPSUM end I resigned from the company. chemical ingredient can be put into the Another industrial mineral that's a Now this lack of communication car- smectite material to help prevent the favorite of mine is gypsum. Gypsum is ries on down through a whole host of ac- swelling by binding the particles white and occurs in flake-shaped units. tivities: tremendous problems are created together. Chemically it is hydrated calcium sulfate, and mistakes are made because often the This procedure has been used very currendy used as a pigment in paints and people at the top don't know what to ask successfully in the construction of high- in plasters. If you drive off about three- or who to ask. Here's just one example of ways around Oslo in Norway. In the fourths of the water that's present, you get this. For years, I was a consultant for the vicinity of Oslo and elsewhere in the Plaster of Paris. Gypsum is tremendous- Bechtel Corporation in San Francisco, a world there are materials that engineers ly abundant worldwide and its deposits huge engineering and construction outfit call "quick" soils. These are soils that are relatively pure. that builds everything from dams to have a high moisture content, and in an About ten years ago, a very good atomic energy plants. The Bechtel Cor- undisturbed condition they are solid and friend of mine in England—a consultant poration has a very large, excellent geol- reasonably strong. But if they are agitated for a company that produced industrial ogy department, and the investigation of they flow like water. In the Oslo area, ter- minerals and chemicals—convinced his the geology prior to construction activity races along streams have suddenly li- company to investigate another possible is very thorough in the Bechtel group. quefied and flowed catastrophically use for gypsum. Two people in the re- One of my early activities with the down into streams. Well, a very bright en- search laboratory began to conduct some company concerned two atomic energy gineer in Oslo conceived of a way to sta- experiments to try to make a "bentone" plants that were built in Spain near Bar- bilize these "quick" soils by treating them material out of gypsum. I was pretty celona. Bechtel didn't have anything to with various chemicals—and this treat- deeply involved in this and spent some do with the construction of these plants ment is so effective that it's been possible time in their laboratory, and one of their they were built by a Spanish public utility to build superhighways across these soils. scientists spent some weeks with me in on the side of a valley above a sizable my laboratory at the University of Il- stream. They had chopped off the end of RESEARCH OPPORTUNITIES linois. I think we had achieved the inter- the broad ridge in the valley wall, cut it Much research remains to be done on calation of organics in gypsum. We had down, and leveled it off. On this newly improving industrial minerals and ex- some X-ray diffraction data that indicated leveled ground, they built two atomic panding their uses. There is tremendous we were on the threshold of really work- energy plants. The bedrock in the area is opportunity for fundamental research in ing that out. Unfortunately, the company a series of Cretaceous sands, clays, and many areas. Gypsum, which is so abun- in England had financial difficulties and gravels. dant worldwide, is basically an untapped went broke, and the project was killed. I Just before the fuel was to be loaded resource. Maybe it could be used to sta- would hope that this type of research on into the first-completed plant the soil bilize soft soils—it certainly has more gypsum will continue. began to swell, and it pushed the plant up uses than just plaster and pigment Some a measurable amount The Spanish en- of the applications for industrial minerals CONSULTING gineers called the Bechtel Corporation, that I've touched on today are in their For many years I have been a consult- wanting to know what caused the rise and early stages—bentonites for radioactive ant to a great many companies involved what they could do about it. Well, the waste disposal, kaolins in the printing in- in industrial minerals. One of the cause of it, as anybody with any dustry, and zeolites for increased produc- problems in consulting is that you must knowledge about clay minerals would tivity in agriculture. The future looks get close to management in order to be suspect right off, was that they had some- promising to me for further research to able to do anything really important. how changed the movement of improve the preparation and expand the Commonly the company that you're a groundwater when they leveled off this uses of this important group of minerals. consultant for is managed by lawyers or hill. You should never do this sort of thing accountants or other people who have lit- if you're going to build a plant in such an The Current State of Industrial Minerals in China

Fred Barnard Consulting Economic Geologist 1835 Alkire Street Golden, Colorado 80401

been felt by Western producers of barite, ABSTRACT fluorite, and rare earths because of falling prices China has in the face of Chinese exports a rich and varied mineral resource base and all the requisite con- during times of weak demand. A positive ditions that tend to stimulate production and utilization ofindustrial minerals: a side to the equation for large, growing population, western producers rapidly increasing living standards, an expanding in- is that China is dustrial base, supplying some high- a growing need for export earnings, facilities for rail and water demand minerals (wollastonite, transport, and abundant low-cost labor. magnesite), and purchasing others (phosphates, Because of the variety ofgeologic terranes in China, virtually every known in- potash, dustrial soda ash, diatomite). mineral occurs in important quantities. Three ancient continental cratons This article provides are rimmed by plate-collision zones having a geological metamorphic belts, ultramafic ter- framework ranes, and for China's industrial igneous complexes; the cratons are locally covered by relatively un- minerals resources, examines the orga- iformed clastic and evaporitic sedimentary rocks. Therefore, the geological nizational basis of the China's industrial environments that lead to the formation of a wide variety industrial of minerals minerals are broadly industry, and attempts to discern distributed around the country. Although mineral production has so some trends for far been concentrated the future. Background in the densely populated eastern half of China, the poten- information for this tialfor article was derived future production is also high in western China, in spite oftransportation from the writer's limitations. geologic work, including examination of In addition to the industrial minerals huge quantities of construction materials used in China, deposits, in several many minerals high regions of China. of unit-value—including asbestos, barite, diamond, fluorite, graphite, pyrophyllite, sillimanite, vermiculite, wollastonite , and minerals of GEOLOGIC SETTING beryllium, boron, and titanium—are of current or potential importance in world Within China's trade. China leads the 9.5 million square world in production ofrare earths and barite. Exports to kilometers (an the world are area 2 percent larger than expected to increase as the immaturity of China's mineral resource the United States), database and transportation a wide variety of system is offset by a growing labor surplus and in- geologic conditions has resulted in en- creasing needforforeign exchange to finance industrialization. vironments suitable for the formation of During the current period of rapid flux in China's economic policy, the for- nearly eigner every industrial mineral com- interested in China's mineralsfaces a challenging business environment. Reorganization modity. Three ancient cratons—the Sino- of central-government agencies into competitive, profit- Korean, the Yangtze, and the motivated units has created rivalries Tarim—are that transcend the traditional commodity- rimmed bound relationships by plate-collision zones with between organizations. At the same time, the economic autonomy metamorphic belts, ophiolites, and ig- of local governments has increased. Private enterprise, in the form of neous complexes Chinese orforeign companies, (fig. 1). Acollision zone may soon become an importantfactor in China's is still forming in industrial minerals industry. the Himalayas. Sedimentary basins, some with evaporite facies, locally cover cratonic and inter- cratonic rocks. Sedimentation (mostly INTRODUCTION ness in China: a rich and varied resource continental-evaporitic in the west China has and been a supplier of industrial base, a large and increasing population, a deltaic-marine in the east) continues in minerals to the world for centuries. rising standard of living, abundant low- many parts of China. Minerals such as borates from the salt cost labor, increasing industrialization, Some degree of correspondence lakes of western China exists and kaolin (named and a growing need for export earnings. between the tectonic units shown on for Gaoling village in Jiangxi province) Although strained to capacity, rail and figure 1 and the distribution have long nourished of certain an export trade for waterborne transport systems are ade- minerals (fig. 2). Asbestos China. About 1273 and chromite Marco Polo described quate in eastern China. typically occur in ophiolites; the mining and processing diamonds of asbestos in During the past few years, Chinese ex- on cratons; bentonite, boron, and what is now Xinjiang potash province. ports of certain industrial minerals have in sedimentary basins; A number of and rare earths, factors have combined to had major impacts on Western producers titanium, and perlite on the margins of create a thriving industrial minerals busi- and consumers. Negative impacts have cratons. Figure 1 Tectonic sketch map of China showing Precambrian cratons, ophiolite belts (dark bands), and selected sedimentary basins (modified from Zhang etal., 1984).

CURRENT PRODUCTION power. Not shown in table 1 is the nesses are expected to generate a profit Most mineral production figures are production trend for each commodity, and wean themselves from the annual officially confidential, and probably no which is upward in most cases as China state budget. At the same time, local complete statistics exist for minerals continues its drive to industrialize and ex- governments (provincial, prefectural, produced and consumed locally in rural port. county, and municipal) have been al- areas. The chapter on China (Chin, 1987) In terms of foreign trade, China's ex- lowed greater autonomy in producing and in the U.S. Bureau of Mines Yearbook in- ports include many minerals important to selling minerals. The long-term aim of cludes production estimates for only modern technology, such as refractories, this policy is to promote efficiency and about 15 industrial mineral commodities, rare earths, and rare metals (beryllium, constructive competition. and many commodity review articles in lithium, niobium, and tantalum). Im- A side effect of the new system has the mining press neglect China al- ported minerals include those used as fer- been blurring of the divisions of respon- together. However, it is apparent that tilizers (phosphate, potash, and sulfur) sibility of the various organizations. This about 60 industrial minerals (excluding and for housing (soda ash for glass, and has produced a large degree of overlap construction materials) are produced in cement). The import list underlines the and competition among minerals- China and about 50 are exported. country's priorities to feed and house a producing organizations. As one ex-

Table 1 is a summary of available data population of 1.1 billion people. ample, the Ministry of Geology and for most industrial minerals produced in Mineral Resources no longer functions

China; it was compiled from a wide INDUSTRY ORGANIZATION solely as a public service, discovering variety of sources. It is apparent that The past five years have seen increas- mineral deposits and disseminating infor- China is the world's leading producer ing decentralization of China's minerals mation; it may now compete directly with (and exporter) of rare earths and barite, industry. Many responsibilities have other agencies for participation in and an important producer of a number of been removed from the bailiwick of minerals development. The result can be other minerals. Taken together, the central-government ministries and interagency competition to the detriment figures in this table indicate China's top delegated to newly established, profit- of the agencies and the frustration of the ranking, along with the United States and oriented government corporations. potential foreign investor. In the positive the U.S.S.R., as an industrial minerals Under the "responsibility system," busi- view, the responsibility system has paved •a i y HEILONGJIANG ;v / } Li, Be t-»i/^x :__ graph* Cr *bent # M\y-*A

JILIN . A ^ ~u N NEI MONGOL ,Jn,\»woll _/'° J y v j\ r LIAONING , J c XINJIANG RE y A^BEliHEBEI'l ^"MdfcO,/"l "M < S GANSU >f tasb \V) /? \ shanxiV ^ , CningVNG- // XIA^., diamB /^ • K ( SHANDONG ) H r QINGHAI r ^ <

/ C" HENAN . f Y iJIANG- V. ^SHAANXI^.perl ,/ XIZANG 3\ ^su V ON HUBEI SICHUAN 3 "J bentB"•X_ \ - y B^perl r-U/v- 1 r e \ asb S,r "^"-^VkaolB \ZHEJIANG "2- ,^ */alum 4 CaF2 JjANGXI^ &? hunan -Nb,Ta' J : \ \ CguizhouI g^aph ^fujianS /n ,

major mines YUNNAN & SUANGXI^^ iUANGDONG \) undeveloped/ X y'P! slightly developed deposits VJ HAINAN 1000 km Zr, Ti(^J

Figure 2 Selected deposits of industrial minerals in China.

the way toward eventual innovative and A major function of CNMC is apparently denum). Besides having primary vigorous respon- management of Chinese in- to provide financing, technical support, sibility in China for rare earths, titanium, dustry. marketing, and international contacts to a chromite, and some rare metals, CNNC It should be apparent from the follow- host of locally managed enterprises in produces a number of industrial minerals ing discussion that designation of a "lead return for joint- venture shares. It also un- as by-products; these include barite, agency" on table 1 is not always a simple dertakes research on nonmetallic fluorite, pyrite, and others. CNNC has a matter, although in most cases one or- minerals and operates colleges of non- gemstones division, mainly for market- ganization is still dominant. metallic minerals technology. ing of by-product gems from pegmatite China Nonmetallic Minerals In- State Administration of Building and placer mines. dustry Corporation (CNMC), the agen- Materials (SABM) has responsibility for The Ministry of cy most Geology and deeply involved in industrial production and processing of aggregates, Minerals Resources (MGMR) func- minerals, was formed in 1985 from por- cement, building stone, glass, and similar tions as China's geological survey. tions of the Ministry of Construction materials. SABM produces industrial During recent years it has become direct- Materials and is responsible for most of diamonds and an array of other minerals ly involved in mining because of the the industrial minerals other than con- in addition to construction materials. profit incentive. No longer does struction MGMR materials. When formed, The Ministry of Chemical Industry routinely pass on the successful results of CNMC was largely an umbrella or- (MCI) mines and processes minerals its exploration programs to other agen- ganization with only one mine—an as- used as chemical feedstocks: potash, cies; now the Ministry often will bestos mine in Qinghai— under its direct phosphate, sulfur, sodium minerals, negotiate an equity interest in its dis- ownership. It now has joint-venture or borates, lithium brines, and a few others. coveries before disclosing data to an sales agreements with scores of locally Most of this ministry's activities are in operating managed agency. For example, MGMR mines and products plants. In petroleum refining and petrochemicals. operates a diamond mine in kimberlite, addition, it sells some 80 mineral com- China National Nonferrous Metals discovered by its own personnel, in Shan- modities, ranging from diamonds to Industry Corporation (CNNC) mines dong province. mudstone, as well as products such as as- and processes a host of nonferrous metals Local governments have always bestos brake linings and diatomite bricks. (including copper, lead, zinc, and molyb- been important elements in China's in- Table 1. Industrial minerals production in China.

Annual prod'n. Supply Lead Commodity (metric tons) status agency Comments

Alunite n.a. exp CNMC Deposits near Wenzhou in Zhejiang province

Andalusite 2,500 exp CNMC Includes kyanite, sillimanite

Asbestos 160,000 exp CNMC Chrysotile and crocidolite; mines in many provinces

Barite 1,000,000 exp CNMC Guangxi largest producer; CNNC also some witherite

Bauxite 500,000 exp CNMC Henan largest producer; refractor; abrasive, and aluminum ore

Liaoning Bentonite 500,000 exp SABM Ca and Na types; mainly

Beryl (BeO) 50 exp CNMC Mostly from Altai pegmatites, Xinjiang

Borates 100,000 even MCI Szaibelyite mine in Liaoning, resources in W. China playas

Cement 180,000,000 imp SABM Official figure; over 5,000 plants, including vertical kilns

Cesium n.a. n.a. n.a. Pegmatite resource in Jiangxi

Chromite 25,000 imp CNNC From Altai Mountains, Xinjiang pigment, Cinnabar n.a. exp'' CNNC Widely used in China as medicine, gemstone

Clays attapulgite n.a. exp CNMC Exported by CNMC Exported by ball clays n.a. exp CNMC CNMC central China kaolin 600.000 varies SABM Mainly mined in sepiolite n.a. Deposits in Hunan

Corundum n.a. exp n.a. Most is artificial

chiolite Cryolite n.a. exp n.a. Includes Diamond 0.04 exp (gem) CNMC Placer and kimberlite mines, imp MGMR Mainly Shandong, also Hunan, Liaoning; (industrial) SABM estimated 80% industrial

in Yunnan, Jilin; Diatomite 50,000 imp CNMC Produced insulation grade

mostly K-spar Feldspar n.a. exp CNMC Widespread, and metallurgical grades; Fluorite 750,000 exp CNNC Acid CNMC largest producer Hunan province

Garnet 4,000 exp CNMC Probably alluvial aquamarine, sapphire, Gemstones, n.a. exp CNNC Includes turquoise, excluding diamond CNMC ruby, amber, etc.

Graphite 180,000 CNMC amorphous exp Hunan largest producer Heilongjiang, Shandong flake exp

Gypsum 10,000,000 even MCI Many deposits, also CNMC anhydrite

Lithium spodumene 15,000 exp CNNC Pegmatite mines, Xinjiang in Qinghai and Xizang brines MCI Resources

Magnesite 3,500,000 exp MCI Mainly from Liaoning Meerschaum Deposit known in Hunan

Mica 25,000 exp CNMC Flake and scrap muscovite, phlogopite, biotite Table 1. continued

Annual prod'n. Supply Lead Commodity (metric tons) status agency Comments

Nepheline syenite n.a. exp? CNMC Offered for export Niobium n.a. exp CNNC In Nei Mongol REE mine Olivine n.a. exp CNMC Offered for export Perlite 500,000 exp SABM Mainly in Henan, Zhejiang Phosphate 12,000,000 imp MCI Largest producer Yunnan Potash (K2o) 50,000 imp MCI Brine production in Qinghai Pyrophyllite 50,000 exp CNMC Large deposits in Zhejiang Rare earths (REO) 15,100 exp CNNC Most from Bayan Obo mine, Nei Mongol; includes yttrium; alsoTh from monazite sands Rubidium n.a. Pegmatite resources, Jiangxi Sericite n.a. exp CNMC Offered for export Silica, n.a. exp Silicon metal produced in chemical grade Qinghai from natural silica Sodium minerals salt 20,000,000 exp Sichuan Basin rock salt; also brines

and sea salt; rock-salt reserves in Jiangsu soda ash 2,400,000 imp Natural (in Nei Mongol) and manufactured sulfates 300,000 exp Natural and manufactured; mirabilite in Nei Mongol Staurolite n.a. No information

Strontium n.a. exp CNMC Celestite production, Sichuan Sulfur elemental 200,000 imp MCI pyrite 2,300,000 imp CNNC Guangdong, Nei Mongol by-product 350,000 imp CNMC Talc 900,000 exp CNMC Largest producer is Liaoning Tantalum n.a. exp CNNC Pegmatites, Xinjiang, Jiangxi Titanium (Ti0 2 ) 30,000 imp CNNC Sponge and oxide production, igneous rocks and beach sands Vermiculite small exp CNMC Produced in Hebei Wollastonite 63,000 exp CNMC Jilin and Hubei have most of production and reserves Zeolites n.a. imp? Chabazite production in Hainan; also synthetics Zircon 15,000 Mostly from small mines on Hainan beach sands

These data were compiled from a wide variety of sources, including U.S. Bureau of Mines (Chin, 1987), Mining Journal, Engineering and Mining Journal Chinese press reports, and the author's notes. Data for fuels, metallic ores, and most construction material are not included Most production figures are estimates for 1987 from unofficial sources. See footnotes for abbreviations. Abbreviations: CNMC China Nonmetallic Minerals Industry Corporation CNNC China National Nonferrous Metals Industry Corporation MCI Ministry of Chemical Industry MGMR Ministry of Geology and Mineral Resources SABM State Administration of Building Materials n.a. data not available exp net export commodity imp net import commodity factors, cer- dustrial minerals business because of the diamonds, and others, are being dis- economic and political but over the next local use of many commodities and the cussed or already under way. tain trends do appear likely labor-intensive nature of many opera- China's business environment has decade: in state of flux since 1976, but tions. With the decentralization and profit been a • The import/export balance for some regulations incentive stimuli of the past few years, since 1984 many laws and minerals will shift as China's industrial local governments have increased their pertaining to contracts, joint ventures, base and consumer segment grow. justice have be- participation in processing and selling the foreign exchange, and • Processed mineral products will further commodities produced. A typical small come codified. Several forms of ventures, displace raw minerals as export items. tax and operation may be entirely local in nature; each with its own particular • Quality control will improve in production is by manual methods, and operational advantages, are open to response to market forces. the bagged ore is sold to buyers from a higher foreign investors in China. Besides • Expansion of mining and processing level of government. Larger operations commonly used equity joint venture, facilities will require increasing in- may be partly mechanized (mainly other vehicles for foreign participation fusions of Western technology, capital, transport, possibly milling) and may have are the contractual joint venture, the and management. a higher level joint- venture partner (such wholly owned foreign enterprise, the • Chinese exports will dominate trade and as CNMC, CNNC, or MCI) to provide foreign company, and the representation will affect the prices of a number of technical input and coordinate purchas- office. commodities, including barite, fluorite, ing and product sales. To the foreigner who opts for involve- graphite, pyrophyllite, natural mag- Local private enterprise has ap- ment in China's industrial minerals busi- nesite, and rare earths. peared at the lowest levels of mineral ness, China offers the advantages of • Domestic demand will require con- production in the form of individuals and abundant raw materials, a desire to tinued imports of fertilizer minerals and small cooperatives producing small develop and export its minerals, and a increasing imports of soda ash, borates, quantities of minerals. Generally these potential for enormous growth in internal and a few other materials. there are aspects of enterprises consist of placer operations or markets. However, Regardless of the degree to which climate that are difficult reworking of dumps. The products are China's business each of these trends develops, China will foreign investor to assimilate, and usually sold to the local village or coun- for the be very much in evidence in the industrial factors must be taken into con- ty government these minerals business in the coming years. China National Metals and Min- sideration in developing a business erals Import and Export Corporation strategy: (1) cultural and bureaucratic ACKNOWLEDGMENTS obstacles to doing business; a thinly (CNIEC) is the key agency involved in (2) The author is grateful to Dr. Fun-Den of transportation, foreign trade of minerals. The corpora- stretched infrastructure Wang for his review of this article. tion deals mainly with semifinished communications, and energy supplies; products and large-tonnage commodities, and (3) uneven technical backgrounds of REFERENCES including including fuels, metals, and some in- Chinese counterpart personnel, Chin, E., 1987, China - 1986: Minerals of the impor- dustrial minerals. a low level of awareness Yearbook, v. IV, U.S. Bureau of tance of marketing and quality control. Mines (also earlier editions). FOREIGN VENTURES IN CHINA Lefond, S.J. [ed.], 1983, Industrial Foreign interests are still a minuscule CURRENT TRENDS minerals and rocks: New York, AIME, minerals Huge strides have been made in the element in China's industrial 1446 p. picture. Foreign participation is usually development of industrial minerals in Zhang, A.M., J.G. Liou, and R.G. starting at the level of mineral processing rather China during the past 10 years, Coleman, 1984, An outline of the plate than mining. Foreign investments in ven- from a base that consisted mainly of con- tectonics of China: Geological materials few traditional tures involving a variety of minerals, in- struction and a Society of American Bulletin, v. 95, p. cluding kaolin, talc, diatomite, graphite, export items. Fulfillment of development 295-312. plans naturally depends on a host of

10 Geology of Six Kentucky Carbonates: Sulfur Sorbents for AFBC

Lance S. Barron Garland R. Dever, Jr. Thomas L. Robl University ofKentucky Kentucky Geological Survey University ofKentucky Ctr. for Applied Energy Research* Lexington, Kentucky 40506 Ctr. for Applied Energy Research* Lexington, Kentucky 40512 Lexington, Kentucky 40512

ABSTRACT utilization efficiency. In addition, limited evaluations of attrition and elutriation Three limestones and three dolostonesfromfive active quarries and one mine were conducted in a 2.54-cm (1-inch) in Kentucky were tested in the 2.7-million-Btulhr atmosphericfluidized-bed com- diameter reactor. On the basis of this bustion (AFBC) pilot plant at the Kentucky Energy Cabinet Laboratory to inves- evaluation, three limestones and three tigate their effectiveness as sulfur sorbents. The three limestones consisted of dolostones were selected for testing in the high-calcium oolitic-peloidal calcarenite from the Ste. Genevieve Limestone pilot plant. (Mississippian); crinoidal, bioclastic calcarenite from the Salem and Warsaw In the research reported in this paper, Limestones (Mississippian); and fossiliferous, bioclastic calcarenite from the six Kentucky carbonates were tested in a Grier Limestone Member of the Lexington Limestone (Ordovician). The three 2.7-million-Btu/hr AFBC pilot plant at dolostones consisted ofthe Oregon Formation (Ordovician), the Laurel Dolomite the Kentucky Energy Cabinet Laboratory (Silurian), and the Renfro Member of the Slade Formation (Mississippian). (KECL) in Lexington, and results of the The dolostones performed better than the limestones as sulfur sorbents, show- pilot-plant tests were compared to results ing higher calcium utilization values, greater sulfur capture capacity, and slight- of bench-scale tests of the sorbents. This ly lower SO2 emission levels. Conversely, the limestones had lower rates of paper includes information on the main attrition and elutriationfrom the bed and slightly lower NOx emission levels. features of AFBC technology, results of The mean grain sizes of the limestones were 550, 800, and 1200 Urn for the the pilot-plant tests, and the geology and Grier, Salem-Warsaw, and Ste. Genevieve, respectively. The mean crystal sizes geochemistry of the limestones and were 42, 86, and 25 \imfor the Oregon, Laurel, and Renfro dolostones, respec- dolostones. The potential importance of tively. Chemically, the six carbonates were composedprimarily ofCaC03, MgC03, dolostones as alternatives to high-cal- andSiOi in the following concentrations: Ste. Genevieve (95.9, 2.1, 1 1) Salem- cium limestone AFBC sorbents is em- Warsaw (90.9, 4.5, 3.0), Grier (87.4, 3.8, 4.7), Oregon (62.4, 31.6, 4.2), Laurel phasized. Test results and engineering (51.5, 39.0, 65), and Renfro (59.4, 26.2, 10.3). information included in this paper were presented at the Ninth International Con- ference on Fluidized Bed Combustion (Barron and others, 1987) and at "Coal INTRODUCTION Carbonate rocks are an integral part of Technology '86" (Barron and others, Limestone and lime have been used to atmospheric-pressure fluidized-bed com- 1986). control sulfur dioxide (SO2) emissions bustion of coal. They capture sulfur from coal-burning electric utility plants released from the burning coal in the AFBC TECHNOLOGY since the early 1970s. At that time, scrub- boiler itself, eliminating the need for Atmospheric fluidized-bed combus- bing represented a new market for lime- downstream scrubbers. tion has been demonstrated at pilot scale stone producers. In 1980, when the The overall goal of this project was to to be an efficient, environmentally ac- National Crushed Stone Association examine the basic chemical and geologi- ceptable method for burning high-sulfur presented a seminar on "Limestone for cal parameters characteristic of some of coal (Castleman, 1985; Tang and others, Flue Gas Scrubbing" (NCSA, 1980), the major carbonate deposits in Kentucky 1983). The AFBC process has only a number one paper dealt with the use of lime- and to identify, by means of bench-scale of advantages, including in-boiler SO2 stones in atmospheric fluidized-bed com- and pilot plant tests, parameters that are removal, low NOx emission levels, high bustion (AFBC), a technology then in the useful in predicting and ranking the per- heat-transfer efficiency, low combustion distant future. This technology came of formance of sorbents in AFBC boilers. temperatures that eliminate slagging and age with the start-up of the 160-megawatt More than 200 samples, representing (MW) a fouling, and a dry, easily handled solid AFBC demonstration plant at the broad range of lithologic types, were col- refuse. In addition, an AFBC boiler can Tennessee Valley Authority's (TVA) lected and analyzed chemically and burn many different types and qualities of Shawnee Steam Plant near Paducah, petrographically. These samples were fuel. Kentucky, in 1988. (See Bass and others, then characterized in a modified ther- Figure 1 is a schematic of the KECL 1987, for an overview of the development mogravimetric analyzer (TGA) for sul- AFBC pilot plant. Washed of Springfield AFBC technology at this facility.) fur-capture capacity and calcium- coal (Western Kentucky No.9) and the sorbent to be tested were delivered by Formerly called the Kentucky Energy Cabinet Laboratory.

11 ' fa L£j COAL

LIMESTONE

RECEIVING BED PRODUCT REMOVAL AND STORAGE BOILER, HEAT RECOVERY AND GAS CLEANING AND STORAGE 16. Heat Exchanger 24. Bed Product Cooler 1 Storage 8. Conveyor Stack Gas 9 Feed Injector 17. Baghouse 25. Bed Product Storage PREPARATION 10 Water Wall Header 18. ID. Fan 26. Fly Ash Storage 11. Air Blower 19. Stack 2 Conveyor 12. Combustor 20 Water Pump 3 Crusher 13. Start-Up Burner 21. Head Tank 4 Screener 14 Hot Cyclone 22. Exhaust Heat to Atmosphere TRANSPORTATION 15 Cyclone Solids Remjection 23 Building Heat AND METERING Disposal Hopper 5 Pneumatic Transporter 6. Day Storage Bin 7. Weigh Belt

Figure 1 Schematic and flow diagram of the AFBC pilot plant. truck to storage bins in the preparation plant for the sorbent tests are listed in PILOT PLANT TESTS plant building. Sorbent was received as No.9 table 1. The purpose of the pilot test was aggregate (-1/2 inch x 4 mesh). Coal was As demonstrated in pilot plants and in to assess the performance of a broad Ken- crushed in the hammer mill to -1/4 inch the construction of demonstration plants range of carbonate lithotypes from and sorbent to -1/8 inch. These size dif- and retrofits, AFBC technology can meet tucky in an industrial-type AFBC unit. ferences reflect the different densities and current emission requirements and has The selected sorbents, representing all fluidizing properties of the materials. the potential to meet even stricter require- the major geologic systems that are com- Coal and sorbent limestone were then ments. Current operating practices re- mercial sources of crushed stone (table pneumatically conveyed to day bins lo- quire calcium-to-sulfur ratios above the 2), were therefore tested under similar pilot cated next to the pilot plant. During theoretical stoichiometry of one mole of conditions in the KECL AFBC operations, coal and sorbent were SO2 per mole of CaO. These ratios range plant. Washed Springfield coal (Western metered across weigh belts and injected up to 3:1, CaO:S02, and even higher for Kentucky No. 9) containing approxi- under-bed into the firebox. The bed of the more stringent emission controls. For mately 3.5 percent sulfur and 8 to 10 per- in series boiler was maintained in a fluidized state these reasons, research into the effects of cent ash was used a test by a force-draft fan providing a superfi- chemical, physical, and geologic conducted at 70, 85,and 100 percent load. cial gas velocity of approximately 5.2 feet parameters of limestones and dolostones Carbon utilization per second. Combustion gases and on AFBC technology has been part of the Carbon utilization values ranged from entrained particulate matter exit at the top research program on this technology. 95 to 99 percent, values comparable to of the combustor and enter a hot-gas cyclone; here the coarse, entrained par- ticulates are removed before the gas Table 1 AFBC pilot plant operating conditions enters a heat exchanger, to be cooled before it enters the fine-particulate Bed area 6.4 ft (0.6 m) removal baghouse. Stack-gas chemistry was monitored Fluidizing air superficial velocity ~5.2ft/s(1.6m/s)

with a Beckman gas analyzer. Spent bed Excess air 20% (at 100% load) material was removed from the bed 100% load 2.7 million Btu/hr through a water-cooled auger. A com- Operating temperature 1500-1600°F(830-880°C) puter-controlled data acquisition system monitored 128 channels of temperature, Feedpoint Under-bed pressure, flow rates, and chemistry of the Cyclone catch No recycle process. Operating conditions of the pilot

12 Table 2. General geologic features of the six pilot plant carbonates tested in the AFBC. .60- Sorbent Geologic Grain/Crystal Number Formation Name System LithologicType Mean Size

1 Oregon Dol. Ordovician Calcareous Dol. Crystals 42u,m c 2 Renfro Dol. Mississippian Calcareous Dol. Crystals 25u.m N2CO .40-: 3 Laurel Dol. Silurian Calcareous Dol. Crystals 86u.m 4 Ste. Genevieve Dol. Mississippian Oolitic Ls. Grains 1200u.m E

5 Salem-Warsaw Ls. Mississippian Bioclastic Ls. Grains 800u.m 03 6 GrierLs. Ordovician FossiliferousLs. Grains 550>m 03 C £ .20 o 03 those obtained in other tests in this pilot Calcium utilization plant. These percentages were higher Calcium utilization values were than those obtained in other AFBC test higher for the dolostones than for the facilities (Castleman, 1985; Tang and limestones (fig. 3); the effect of higher others, 1983). However, the differences calcium utilization was of course reduced .00- J_ in test results can be explained by the ab- somewhat by the higher calcium contents Limestone sence of a sorbents convection-pass heat ex- of the limestones. changer in the freeboard area (the area Figure 3 Maximum fractional calcium utiliza- between the top of the bed and the top of tion observed in the KECL pilot plant for each carbonate the combustor) of this pilot plant. The ef- rock tested (Barron and others 1986). fect of the heat exchanger in the other units is to lower the temperature of that also demonstrates that the dolostones are zone to below combustion levels; thus, less sensitive to sorbent feed rate than are any unbumed or pardy burned coal car- the limestones (as reflected by higher cal- ried into the zone would not be burned, cium utilization and lower SO2 emissions and carbon utilization, as measured in the for the dolostones). ash, would be lower. Because the pilot plant had no heat exchanger to reduce the SELECTION OF SORBENTS temperature in this unit, elutriated coal The limestones and dolostones continued to burn in the freeboard, and selected for testing were obtained from the carbon content in the ash was lower active .40 quarries or mines in stone-produc- than it would have been if the tempera- 1 S 1 ing areas of Kentucky; they represented a ture had been reduced. CD variety of carbonate lithotypes and were Emission levels lithologically homogeneous. 20 y I ? Data on NOx emission levels in the six i?i 100 tests (fig. 2) indicate that all test results were well below the NOx emission stan- .00 T 1 T dard of 0.6 lbs NO* per million Btu (MMBtu), as expected with AFBC units & f S> ,9 & (Castleman, 1985; Furusawa and others, 1978; Hansen and others, 1983). The Figure 2 Emission levels of SO2 and NOx for l {!,« dolostones had slightly higher the NOx levels six carbonates tested in the AFBC pilot than the limestones. plant. The uppermost and SO2 emission levels lowermost lines *75 D (whiskers) for each data set for all carbonates were below the 1.2 lbs denote the range of values, the ends of the boxes mark the quar- SO2 /MMBtu emission standard. Lower tiles, and the line in the box is the median of the SO2 levels were achieved with the dolo- data for • Oregon Dol that test (Barron and others, 1 987). Renfro Dol stones, partly because of the greater reac- a Laurel Dol tivity of dolostones and partly because of Sulfur capture capacity Ste. Genevieve Ls the slightly higher sorbent feed rates. Be- Salem-Warsaw Ls cause In these tests, sulfur capture was af- the dolostones had lower SO2 a Grier Ls fected by sorbent feed 50 levels, the higher NO* levels rate (fig. 4), a result were 0.0 0.25 0.50 consistent with results obtained by others probably related to increased sulfation of Stone-to-coal weight feed (Castleman, ratio the dolostones. Other researchers 1985; Tang and others, 1983). This finding supports the Figure 4 Stone-to-coal weight ratio versus sul- (CasUeman, 1985; Furusawa and others, concept fur capture that increasing percentage. The scatter in the data 1978) have reported on the amount of sorbent fed tests of partly sul- is due to different operating conditions, such as fated at a given coal feed rate will reduce stone beds. bed height, excess air, and load (Barron and utilization efficiency. The plot in figure 4 others, 1986).

13 1. Ste Genevieve Ls. Limestone production area

2. Salem-WarsawLs.

3. RenfroDol.

4. Laurel Dol

5. GrierLs 6. Oregon Dol.

Figure 5 Locations of the quarries that supplied carbonate rocks for the AFBC pilot plant tests, shown in relationship to the major limestone-producing areas and coal fields of Kentucky.

In previous research at the KECL Genevieve Limestones (the principal (Middle Ordovician), a thick (430 to 570 AFBC pilot plant, various Kentucky sources of stone in the area) had already ft) sequence of limestone and dolostone coals were tested, but only one locally been used as sorbents in the TVA20-MW (fig. 7). The Oregon is composed of cal- available carbonate sorbent, the Oregon pilot plant near Paducah, Kentucky. careous dolostone commonly inter- Formation, was used in all runs. In the bedded with calcilutite. The dolostone is current phase of research, the sorbent GEOCHEMISTRY OF SORBENTS yellowish gray to yellowish brown, intri- characteristics of six carbonate rocks The concentration of CaC03 in the cately mottled with dark gray; it is finely were determined, but the same high-sul- three limestones ranged from 85 to 95 crystalline and thick bedded. Microscopi- fur Springfield coal (Western Kentucky percent; the MgC03 content of each lime- cally, it consists of a mixture of anhedral No. 9) was used in all runs. stone was less than 5 percent (fig. 6). The and euhedral dolomite crystals with small Three dolostone and three limestone total content of inerts (mostly quartz and scattered patches of calcite microspar lithotypes were selected because bench- clay) for each limestone was below 5 per- (fig. 9). The dolomite crystals generally scale testing of carbonate rocks from cent. Two of the limestones, the Ste. have dark boundaries. The size of the across Kentucky had indicated that both Genevieve and the Salem-Warsaw, were dolomite crystals (measured along ap- dolostones and limestones were poten- high-carbonate stones (CaC03 + MgC03 parent long axes) averaged 44 urn in the tially suitable for use in AFBC plants. >95%); the Ste. Genevieve was a high- long dimension. Testing at KECL, and at other calcium limestone (>95% CaC03). The The High Bridge Group, the oldest laboratories (Borgwardt and Harvey, MgC03 content of the calcareous dolo- strata exposed in Kentucky, crops out on 1972; Harvey and Steinmetz, 1972; stones ranged from 25 to 36 percent (fig. me Cincinnati Arch in central Kentucky Snyder, Fuchs, and Wilson, 1978), indi- 6), short of the MgC03 concentration re- along valleys of the entrenched Kentucky cated that different carbonate lithologies quired for true dolomites in the strict in- River (fig. 10) and its tributaries; it is at reacted differendy in the calcining/sulfat- dustrial sense (40 to 43% MgC03). The minable depth beneath a large part of ing AFBC environment; therefore, total content of inerts (mostly Si02, central and north-central Kentucky. The lithologically homogeneous sorbent quartz or chert primarily) for each dolo- Oregon Formation ranges from 6 to 65 feedstocks were sought in this study to stone ranged from 6 to 14 percent, higher feet thick (Cressman and Noger, 1976). facilitate interpretation of study results. than in the limestones. Construction and agricultural stone This requirement eliminated many quar- are produced from the Oregon at six un- ries and mines as potential sources of GEOLOGY OF SORBENTS derground mines in central Kentucky. stone because their active faces contained The three dolostones and three lime- The dolostone tested in the AFBC pilot a mixture of carbonate lithologies. stones are described separately, in as- plant was obtained from the Central Rock We obtained stone only from active cending stratigraphic order, in the Company mine in Lexington, Fayette operations (fig. 5) because relatively following sections. Stratigraphic posi- County, where the formation is 28 feet large quantities of stone were required for tions of the carbonate units are shown in thick. At the time the stone was taken for the test runs and because we wanted to figures 7 and 8 and general characteris- testing, a bench in the lower 17 feet of the document potential sources of sorbent tics are summarized in table 2. formation was being mined. Five of the stone for future AFBC plants. No stone operations in the Oregon, including the Dolostones was obtained from the western part of the Central Rock Company mine, also Oregon Formation The Oregon For- Mississippian Plateau Region in western produce stone from the basal part of the mation is part of the High Bridge Group Kentucky because the Warsaw and Ste. overlying Tyrone Limestone.

14 '

T-TT

Laurel

Feet Feet 1,000 1,000-

— 500 v Ste. 500 — ' Genevieve

Tjrn. Grier

Renfro

Oregon

Salem- 0— Warsaw

CaC0 MgC0 Si0 3 3 2 Al 2 3 Fe2 3 K2

Chemical composition

Figure 6 Chemical compositions (weight per- Figure Stratigraphic 7 positions of Ordovician Figure 8 Stratigraphic positions cent) of Mississip- of the six carbonate rocks tested in the and Silurian carbonate units on a generalized pian carbonate units on a generalized colum- AFBC pilot plant. columnar section for surface rocks in Kentucky. nar section for surface rocks in Kentucky. Laurel Dolomite The Laurel Dolo- west-central Kentucky; the belt extends finely crystalline; it is light gray and mite (Middle Silurian, fig. 7) is composed from Trimble County on the Ohio River weathers rapidly to yellowish orange or of light gray to olive gray calcareous southward for a distance of about 80 grayish orange. Microscopically, the dolostone with minor amounts of shale in miles into western Marion County. (Pre- Renfro consists mostly of euhedral to an- partings and thin beds. The dolostone Middle Devonian erosion truncated the hedral dolomite crystals (fig. 14); it has a mainly consists of two types termed information at the southern end of the belt.) 4 percent ankerite content and small (10 formally the " vuggy " stone and the "quar- The Laurel also crops out in south-central Mm) crystals of calcite. The average ry" stone (Peterson, 1981). The "vuggy" Kentucky in a small area along the Ken- dolomite crystal size (measured along ap- dolostone is finely to medium crystalline, tucky-Tennessee border. In many places parent long axes) is 25 urn. The dolomite very porous, fossiliferous, and massive to the Laurel is 40 to 55 feet thick; its max- has a ferroan dolomite content of about thin bedded; it forms extremely pitted, imum thickness is 65 feet (Peterson, 33 percent, as determined by potassium weathered surfaces. The "quarry" stone is 1981). Construction and agricultural ferrocyanide staining. The dolostone has finely to very finely crystalline, porous, stone are produced from the Laurel at very fine intercrystalline porosity and ir- and sparsely fossiliferous; it occurs in three quarries and two underground regular patches of calcilutite. thin to thick planar beds and forms dense, mines in the western Blue Grass Region. Mississippian limestones and dolo- smooth, rounded surfaces in weathered Working faces encompass both the stones crop out along the western border exposures. In a quarry face of the Laurel "vuggy" dolostone and the "quarry" of the Eastern Kentucky Coal Field in a shown in figure 11, the "quarry" stone stone. The dolostone tested in the AFBC northeastward-trending belt extending overlies the "vuggy" stone. pilot plant was obtained from a 22-foot across south-central, east-central, and Porosity in the formation is mainly face in the upper Laurel (fig. 11) at the northeastern Kentucky from the Ten- biomoldic and partly intercrystalline. In Medusa Aggregates Company's nessee state line to the Ohio River. The thin section (fig. 12), the Laurel consists Bardstown quarry in Nelson County. name Renfro is applied in east-central primarily of euhedral dolomite rhom- Renfro Member of the Slade For- and northeastern Kentucky bohedra with to the dolo- patches of calcite mation The Renfro Member, the basal stone at the base of this carbonate se- microspar. The average size of the unit of the limestone-dominated Slade quence. In south-central Kentucky, dolomite rocks crystals, measured along ap- Formation (Mississippian; see fig. 8), is correlative with the Renfro are thicker parent long axes, was 88 |im. composed mostly of calcareous dolo- and more varied in lithology; they form, The Laurel crops out in a narrow belt stone interbedded with limestone and in descending order, middle along and lower the western border of the Outer shale. The dolostone is thick bedded to parts of the St. Louis Limestone, Salem Blue Grass Region in north-central and thin bedded (fig. 13), and very finely to and Warsaw Limestones, and the

15 Figure 9 Photomicrograph of the Oregon For- Figure 10 Roadcut in the Ordovician High Bridge Group along U.S. Highway 27 as it crosses the mation from the Central Rock Company mine Kentucky River in Jessamine County, Kentucky. Base of the Oregon Formation is near the shale in Fayette County, Kentucky. Average crystal parting just above the top of the car. The next significant shale parting is in the base of the oversize is 44 |im in the long dimension. lying Tyrone Limestone.

Muldraugh Member of the Borden For- mation (Dever and Moody, 1979). The Renfro thins northeastward across the outcrop belt, from 120 feet in southern east-central Kentucky to 2 feet in northeastern Kentucky. Intra-Mississippian erosion removed the Renfro from parts of northeastern and northern east-central Kentucky. The dolostone tested in the AFBC pilot plant was obtained from the Natural Bridge Stone Company quarry in Powell County, where Slade limestones overlying the Renfro are quarried for construction stone. A bench of about 15 feet of upper Renfro dolostone was excavated from below the quarry floor (fig. 13) but SW^ra^sE. the stone did not meet construction-stone ^Kan specifications. Stone from a stock pile of Figure 11 Quarry face of the Silurian Laurel Dolomite in the Medusa Aggregates Company Bardstown quarry in Nelson County, Kentucky, showing bedded "quarry stone" overlying the waste dolostone was prepared as No. pitted "vuggy" dolostone. 9 aggregate for use in the AFBC pilot plant. Commercial use of the dolostone in the region presently is limited to one underground operation in south-central Kentucky, where St. Louis dolostone and limestone correlative with the Renfro are mined for agricultural and construction stone. Renfro dolostone would be readily exploitable at many active quarries and mines in the region where the top of the member is a short distance below or at the present floor. Potential exploitation of the Renfro will be somewhat restricted in southern east-central Kentucky, however, because in this region its lower part con- Figure 12 Photomicrograph of the sists mostly of cherty and geodiferous Laurel Dolomite from the Medusa Aggregates quarry. Average crystal dolostones. Nodular quartz, associated size is 88 urn in the long dimension.

16 with brecciated dolostone, also occurs in Limestones reflecting the large size range in fossil the upper part of the member. These Grier Limestone Member of the fragments. deleterious constituents generally are ab- Lexington Limestone The Grier Lime- The Grier crops out in central and sent in the Renfro of northern east-central stone Member of the Lexington Lime- north-central Kentucky, across the Inner and northeastern Kentucky. stone (Middle Ordovician, fig. 7) consists Blue Grass Region and along the valley of fossiliferous calcarenite and calcisilute of the Licking River. Its wide variation and minor amounts of calcilutite. Shale in thickness (60 to 180 ft) reflects inter- partings are common. The limestone, tonguing with adjacent members of the light brownish gray to pale yellowish Lexington Limestone (Cressman, 1973). brown and medium dark gray to light Construction and agricultural stone olive gray, is cemented by medium to are produced from the Grier, commonly coarsely crystalline sparry calcite; whole along with adjacent members of the Lex- and fragmented fossils are partly recrys- ington, at seven quarries in central and tallized. Beds are thin to medium, ir- north-central Kentucky. The limestone regular, nodular, and tabular (fig. 15), and for the AFBC pilot plant was obtained scattered fossils are replaced by gray from the Nally & Gibson Georgetown, chert. In thin section (fig. 16), the Grier is Incorporated quarry from a 55-foot face composed of about 50 percent medium to in the upper Grier (fig. 15). The base of coarse calcite spar and 40 percent calcite the member is not exposed at the quarry, microspar; the remaining 10 percent con- but the Grier is about 130 feet thick in the sists of dolomite and microcrystalline vicinity (Cressman, 1973). calcite. Mean grain size (measured along Salem and Warsaw Limestones The apparent long dimensions) is 550 pm, Salem Limestone and Warsaw Limestone (Mississippian) of south-central Ken-

Figure 13 Upper part of the cut in the Renfro Member of the Slade Formation in the Natural Bridge Stone Company Quarry in Powell Coun- ty, Kentucky. The hand of the person in the photograph is at the contact between the Renfro and the overlying St. Louis member.

Figure Quarry 15 face of the Grier Limestone Member of the Ordovician Lexington Limestone in the Nally & Gibson Georgetown quarry in Scott County, Kentucky.

Figure 16 Photomicrograph of the Grier Limestone Member of the Lex- Figure 14 Photomicrograph of the Renfro ington Limestone showing dolomite Member of the Slade Formation. Average crys- crystals within a folded trilobite frag- tal size along the longest grain axis is 25 u.m. ment.

17 r'_> - ^»>*.

Figure 17 Quarry face of the Mississippian Salem-Warsaw Limestones in the Southern Ag- gregates quarry in Allen County, Kentucky. The top of the petroleum-stained zone at the base of the face is approximately 1 2 feet above the quarry floor.

Figure 18 Photomicrograph of the Salem-War- saw Limestones showing pelmatozoan fragments. Average grain size is 800 |im along the longest dimension.

tucky were combined into one mapping

unit, Salem-Warsaw Limestones (fig. 8), during the U.S. Geological Survey-Ken- tucky Geological Survey cooperative mapping project (1960 to 1978). The unit is composed of crinoidal calcarenite and contains zones of sandstone, argillaceous

dolomite, and shale. The calcarenite is medium gray to olive black, partly fossiliferous and locally dolomitic and con-

tains minor amounts of chert; it is thin Figure 19 Quarry face of the Mississippian Ste. Genevieve Limestone in the Kentucky Stone bedded to thick bedded (fig. 17) and com- Company Irvington quarry in Breckinridge County, Kentucky. The high-calcium ledge is the monly cross bedded. In thin section, crossbedded, lighter colored unit at the base pelmatozoan particles—the principal constituent (fig. 18)—and smaller amounts of bryozoan particles are both cemented with clear sparry calcite. About one-third of the pelmatozoan fragments have syntaxial rim cement; minor constituents include mollusks, algae, and dolomite crystals. Mean grain size (measured along apparent long dimensions) is 800 pin. The Salem and Warsaw Limestones crop out in the Mississippian Plateau Region across south-central Kentucky, from Simpson and Warren Counties Figure 20 Photomicrograph of the eastward into Wayne and Pulaski Coun- Ste. Genevieve Limestone show- ties. The unit thickness ing ooliths, micrite-enveloped ranges from 35 to grains, and spar cement. Average 170 feet. grain size in the longest dimension Construction and agricultural stone is 1200 urn. are produced from the Salem-Warsaw at

18 Table 3 TGA experimental conditions. (1972) and Snyder, Wilson, and Johnson (1978) (see Barron and Sample mass 45-60 mg others, 1987). In a TGA test, a sample of limestone is Sample particle size 850 M-m - 1 mm (No. 18 X 20 seive) placed in a quartz pan on a microbalance. Operating temperature 1600°F(870°C) The arm of the balance is placed in a fur- Gas flow rate 8.3 ml/s nace operated isothermally at 87°C. The Calcining gas composition sample is calcined (table 3) for 30 N2,81.5%; C02 ,16%; 2 ,2.5% minutes and then exposed to S02-bearing Calcining time 30 minutes gas for almost 3 hours. During calcina- Sulfating gas composition N ,75.2%; tion and 2 C02 ,16%; 2,2.5%; SO2 ,0.3% sulfation, the microbalance Sulfating time 160 minutes records weight loss and weight gain. The resulting data can be used to calculate sulfation capacity and calcium utilization two quarries in south-central Kentucky. near the quarry (Dever and others, 1979). (combined with chemical content). Table The limestone for the AFBC pilot plant The quarry produces construction stone 3 outlines the experimental was conditions. obtained from the Southern Ag- from the lower part of the formation. A One of the parameters derived from gregates, Incorporated Scottsville quarry lithologically similar high-calcium cal- the TGA tests is calcium utilization, in Allen County, from an 80-foot face carenite from the Ste. Genevieve in which provides a simple, first look at per- (fig. 17) in a unit having a total thickness Caldwell County has been used in the formance of candidate limestones. Cal- of about 1 10 feet near the quarry (Ketner, TVA 20-MW AFBC pilot plant at the cium-utilization values determined by 1962). Shawnee Steam Plant near Paducah in TGA differ from calcium-utilization Ste. Genevieve Limestone The Ste. western Kentucky. values obtained in the Genevieve pilot plant. The Limestone (Upper Mississip- The light gray to white "oolitic" cal- data plotted in figure 21 demonstrate the pian, fig. 8) consists mostly of limestone carenite at Irvington consists of micrite- differences between limestone and dolo- (calcarenite and calcilutite), with smaller enveloped bioclastic grains and peloids stone values obtained from TGA data amounts and of dolostone, shale, sandstone, (micritized, algal-bored grains). True from pilot plant performance results. For and chert. The limestone is white to olive oolites were rare. In thin section (fig. 20) the dolostones, calcium utilization values gray, partly fossiliferous, thinbedded to the principal volumetric constituents, in obtained in pilot plant tests were lower thickbedded, and partly crossbedded (fig. descending order, are sparry calcite ce- than expected on the basis of TGA data. 19). Calcarenites are composed of Conversely, for the limestones, calcium bioclastic, micrite-enveloped peloidal utilization values were higher in the pilot and oolitic grains. plant results than in the TGA results. Al- The Ste. Genevieve en crops out in the o though utilization only six data points are available Mississippian Plateau Region of western • to work with at this time, it appears that and west-central Kentucky. Equivalent *» / the TGA-derived calcium utilization limestones in the Monteagle Limestone, (3-40- number is useful for screening purposes. Slade Formation, and Newman Lime- plant stone crop out in south-central, east- o 20 SUMMARY central, and southeastern Kentucky, a. • Six commercially produced Kentucky respectively. The thickness of the Ste. Dolomites carbonates were successfully Genevieve • Limestones tested as and its equivalents ranges .00- J AFBC sulfur sorbents in the AFBC pilot from 320 feet in western Kentucky 0.0 0.2 0.4 0.6 0.8 to less plant at the TGA calcium Kentucky Energy Cabinet than 10 feet in east-central Kentucky. utilization Laboratory; all limestones and dolo- Intra-Mississippian erosion removed the Figure 21 Comparison of calcium utilization stones achieved NO and levels data x SO2 at Ste. Genevieve equivalent from north- obtained from the TGA with that observed or below the emission standards. in the pilot plant tests. The single line repre- eastern and parts of northern east-central sents ideal 1 :1 relationship; the double •The three calcareous dolomites Kentucky. line represents a least-squares regression through the demonstrated greater sulfur dioxide Construction, agricultural, and in- six data points (Barron and others, 1987). capture and calcium utilization and dustrial stone are produced from the Ste. lower sulfur dioxide emission levels Genevieve (commonly together with ad- ment, micrite-enveloped grains, and than the limestones did. jacent limestone units) at 38 quarries and peloids. Minor constituents include bio- • The three limestones exhibited lower mines in the state. The limestone for the clasts, dolomite, and trace amounts of NOx emissions and required lower feed AFBC pilot plant was obtained from the chalcedony. Mean grain size in the rates of stone than the dolomites. Kentucky Stone Company's Irvington longest dimension is 1200 Jim. • The high-calcium Ste. Genevieve lime- quarry in Breckinridge County, where a stone performed better than the bio- 17-foot deposit of high-calcium "oolitic" THERMOGRAVIMETRIC clastic and fossiliferous limestones. calcarenite (fig. 19) is selectively quar- ANALYSIS RESULTS • TGA calcium-utilization data cor- ried for industrial use. The top of the cal- Thermogravimetric analyses (TGA) responded well with actual pilot plant carenite is 34 feet below the top of the Ste. were conducted on an apparatus pat- performance for all six carbonate rocks. Genevieve, which is about 200 feet thick terned after Ruth, Squires, and Graff

19 ACKNOWLEDGMENTS Castleman, J.M., 1985, Process perfor- commercial utility AFBC design as- This research was funded by the Com- mance of the TVA 20-MW atmos- sessment: EPRI Interim Report CS- monwealth of Kentucky, Kentucky Ener- pheric fluidized bed combustion pilot 2930, Babcock & Wilcox Company. gy Cabinet. Essential contributions were plant, in Proceedings of the Eighth In- Harvey, R.D. and J.C. Steinmetz, 1972, made by the KECL AFBC Operations ternational Conference on Fluidized Petrographic properties of carbonate Group, the limestone TGA laboratory, the Bed Combustion: DOE/METC-85/ rocks related to their sorption of sulfur limestone analysis laboratory, the coal 6021, v.I, p. 196-207. dioxide: Illinois State Geological Sur- analysis laboratory, and the KECL Publi- Cressman, E.R., 1973, Lithostratigraphy vey, Environmental Geology Notes cations Group. The contributions of Jack and depositional environments of the 50, 37 p. R. Moody of the Kentucky Geological Lexington Limestone (Ordovician) of Ketner.K.B., 1962, Geology of the Scot- Survey in field work, sampling, and dis- central Kentucky: U.S. Geological tsville quadrangle, Kentucky: U.S. cussions were critical to this project, and Survey Professional Paper 768, 61 p. Geological Survey Geologic Quad- the earlier work of S. Adibhatla at the Cressman, E.R., and M.C. Noger, 1976, rangle Map GQ184, scale 1:24,000. KECL is gratefully acknowledged. We Tidal-flat carbonate environments in National Crushed Stone Association, are also grateful to the companies that the High Bridge Group (Middle Or- 1980, Proceedings, National Crushed furnished stone for the test series. dovician) of central Kentucky: Ken- Stone Association Seminar, Lime- tucky Geological Survey, series 10, stone for Flue Gas Scrubbing, Hous-

REFERENCES Report of Investigations 18, 15 p. ton, TX, January 1980. Barron, L.S., D J. Collins, J. R. Hasler, T. Dever, G.R., Jr., P. McGrain, G.W. Peterson, W.L., 1981, Lithostratigrapy of

L. Robl, J.L. Schaefer, and J.C. Wang, Ellsworth, Jr., and J.R. Moody, 1979, the Silurian rocks exposed on the west 1986, Performance of Kentucky sulfur Features in the upper Ste. Genevieve side of the Cincinnati Arch in Ken- sorbents in AFBC: presented at Coal of west-central Kentucky, in Etten- tucky: U.S. Geological Survey Profes- Technology '86, Pittsburgh, PA, Ken- sohn, F. R., and G.R. Dever, Jr. [eds.], sional Paper 1151-C, 29 p. tucky Energy Cabinet Laboratory Carboniferous geology from the Ap- Ruth, L. A., A.M. Squires, and R.A. Graff,

Technical Paper TP24-86, 22 p. palachian Basin to the Illinois Basin 1972, Desulfurization of fuels with Barron, L.S., J.C.Z. Wang, J.L.Schaefer, through eastern Ohio and Kentucky. half-calcined dolomite: first kinetic T.MJones, J.R. Hasler, DJ. Collins, Field Trip No. 4, Ninth International data: Environmental Science and and T.L. Robl, 1987, AFBC pilot plant Congress of Carboniferous Stratig- Technology, v. 6, p. 1009-1014. test of six Kentucky limestones, in raphy and Geology: Lexington, KY, Snyder, R.B., H.L. Fuchs, and W.I. Wil- Mustonen, John P. [ed.], Proceedings University of Kentucky, p. 261-263. son, 1978, Petrographic examination

of the 1987 International Conference Dever, G.R., Jr., and J.R. Moody, 1979, of limestones: Argonne National on Fluidized Bed Combustion: The Review of the lithostratigraphy of the Laboratory, ANL/CEN/FE-78-4, p. American Society of Mechanical En- Renfro Member of the Borden Forma- 10-46.

gineers, v. I, p. 474-480. tion (Mississippian), east-central Ken- Snyder, R., W.I. Wilson, and I. Johnson, Bass, J.W., IB, J.L. Golden, B.M. Long, tucky: Geological Society of America 1978, Limestone reactivities with SO2

R.L. Lumpkin, Jr., and A.M. Abstracts with Programs, v. 1 1, p. 176- as determined by thermogravimetric Mawaker, 1987, Overview of the 177. analysis and as measured in pilot scale

utility development of AFBC technol- Furusawa, T, T. Honda, J. Takano, and D. fluidized-bed coal combustors: Ther- ogy Tennessee Valley Authority Kunii, 1978, Abatementof nitricoxide mochimica Acta, v. 26, p. 257-267. (TVA), in Proceedings of the 1987 In- emission in fluidized bed combustion Tang, J.T., J.N. Duqum, T. M. Modrak, ternational Conference on Fluidized of coal: Journal of Chemical En- and C.J. Aulisio, 1983, An overall 6' Bed Combustion: The American gineering of Japan, v. 11, p. 377-384; review of the EPRI/B&W 6' x

Society of Mechanical Engineers, v. I, cited in Hansen and others, 1983. fluidized bed combustion test facility: p. 146-152. Hansen, W A., J.M. Bloss, PL. Daniel, R. Proceedings of the Seventh Interna- Borgwardt, R.H., and R.D. Harvey, 1972, P. Apa, W.C. Lapple, J.A. Lewis, K.L. tional Conference on Fluidized Bed Properties of carbonate rocks related Loudin, T.M. Modrak, T.A. Morris, J. Combustion, DOE/METC/83-48, p. to SO2 reactivity, Environmental T. Tang, and V. K. Viliamas, 1983, 6- 373-380. Science and Technology, v. 6, p. 350- x 6-ft atmospheric fluidized-bed com- 360. bustion development facility and

20 —

Possible Underground Mining of Limestone and Dolomite in Central Illinois

James W. Baxter Illinois State Geological Survey Champaign, Illinois 61820

and in some situations underground min- ABSTRACT ing becomes the preferred mining method (Baxter, 1980). An 11 -county area in central Illinois that produces little or no crushed lime- This preliminary stone or assessment of the dolomite for use as construction aggregate includes several major feasibility of underground mining of downstate metropolitan centers: Bloomington-Normal, Champaign-Urbana, limestone and dolomite Decatur, Peoria, and is based largely Springfield. In much of this area quarriable thicknesses of on published information of the Illinois limestone or dolomite either do not exist or lie beneath excessive thicknesses of State Geological Survey drift and and interpreta- younger, predominantly clastic bedrock of the Pennsylvanian System. tions by the author. Preliminary studies indicate that underground mining of sub-Pennsylvanian limestone or dolomite formations could provide new sources of limestone and LIMESTONE AND dolomite in central DOLOMITE Illinois to meet the growing needfor crushed stone. Poten- OUTCROPS AND QUARRIES tial targets include the Valmeyeran (middle Mississippian) Ste. Genevieve, St. The pattern of stone production in Il- Louis, and Burlington; the Middle Devonian Cedar Valley, Wapsipinicon, and linois reflects the Grand Tower; distribution of outcrops the Niagaran (upper Silurian) Racine; and Champlainian (mid- imposed by the structural configuration dle Ordovician) Galena Group. of the Illinois Basin, the sedimentary A detailed his- investigation ofthe depth to minable stone, the chemical andphysi- tory of the Basin, and subsequent glacial cal characteristics of the stone, and the specific factors thatfavor underground events. The following discussion mining operations of out- could lead to profitable mining operations in central Illinois, crops and quarries is limited to strati- where both the resources and the market are present. graphic units considered to be targets for underground mining in central Illinois. The bedrock surface is covered by gla- INTRODUCTION in Illinois in recent years has come from cial drift (fig. 3) that either obscures or Illinois has been a leading producer of dolomite quarries in Cook County alone. deeply buries the bedrock (fig. 4) and is limestone and dolomite rock products for An 11 -county region in central Il- thickest in the central Illinois area. Strata many years. In 1988, Illinois ranked sixth linois has little or no crushed stone of Pennsylvanian among age, which are domi- crushed stone-producing states limestone or dolomite. In this region, nantly clastic, underlie the drift in a large with production of 54.3 million tons. construction companies needing material part of the central region. Limestones of Major quarries serving the metropolitan for concrete and bituminous aggregate Pennsylvanian age are generally thin and Chicago area are among the largest in the traditionally used natural or crushed discontinuous and commonly contain in- United States (Mikulic, 1988). However, gravel of glacial (Quaternary) origin (fig. terbedded shale. Pennsylvanian lime- although quarriable deposits in Illinois 2) or trucked in stone from quarries in stones are quarriable where they attain may appear to be practically inex- nearby Livingston, Vermilion, Mont- workable thicknesses of acceptable haustible, the resources are not at all gomery, Clark, Coles, Christian, Menard, quality and the overburden is manageable evenly distributed geographically, and it Logan, and Douglas counties. (These (Goodwin, 1983). is becoming increasingly difficult for sources also provide agricultural lime- Mississippian limestones, particularly producers to supply the demands of major stone.) But demand for limestone and the thick formations of Valmeyeran downstate age, markets for high-quality ag- dolomite is growing and transportation are prime sources of crushed stone in gregates. costs are escalating; moreover, many lo- southern and western Major Illinois (Goodwin, production of limestone for ag- cal gravels are not suitable for highway 1983); the limestone quarries are largely gregate in Illinois (fig. 1) has occurred in construction and some other uses. restricted to areas in and adjacent to the counties near the southern and western Most of the stone produced in Illinois bluffs of the Ohio, Mississippi, and Il- borders of the state—in or adjacent to the is won by open-pit mining methods, and linois Rivers. Some of these limestones bluffs of the Ohio and Mississippi Rivers without doubt, when conditions are tend to be soft and lack the soundness re- and, to a lesser extent, along the Illinois favorable, surface mining is more quired for use in Portland cement and River. Most dolomite is produced in the profitable than underground methods. bituminous mixes. northernmost counties; approximately However, in some cases, geological, en- Quarries in rocks of Devonian one-fourth age are of the crushed stone produced vironmental, and economical factors can restricted mostly to areas adjacent to the make underground mining profitable, Mississippi River in Rock Island and ad-

21 Figure 1 . Sources of crushed limestone or dolomite concrete Figure 2. Sand and gravel pits. aggregate in Illinois (IDOT, 1986). joining counties (Goodwin, 1983). Mid- is the backbone of the aggregate and lime to the south and the handle to the north dle Devonian limestone is quarried in the industries in northeastern Dlinois. (Willman et al., 1967). As the surface of vicinity of the Quad Cities in Rock Island Carbonate strata of the Ordovician the Precambrian basement gradually County and near Tuscola in Douglas System crop out extensively in north- sank, infilling Paleozoic sediments were County, where units of this age reach the western and north-central Illinois being deposited. The Paleozoic units dip bedrock surface at the crest of the La Salle (Willman and Kolata, 1978) and are ex- toward the center of the Basin, and the ag- Anticlinal Belt. posed at a few sites along the Mississippi gregate thickness of infilling strata Carbonate rocks of the Silurian Sys- River in western and southern Illinois. generally increases toward the deeper tem (Willman, 1972) are found at the Formations of the Galena and Platteville portions of the basin, as illustrated by an bedrock surface in northern Illinois, Groups are quarried at numerous loca- east-west cross section through central Il- where they are predominantly dolomite, tions in northern Illinois (Goodwin, linois (fig. 5). This relatively simple pic- and at places along the Mississippi River 1983). A high-quality stone at the top of ture is complicated by the major erosional in southern Illinois, where they are lime- the Galena is mined underground at unconformity at the base of the Absaroka stone (Goodwin, 1983). High-purity Elmhurst in Du Page County. (base of the Pennsylvanian). From south dolomite (greater than 42% magnesium The distribution of limestone outcrops to north, progressively older stratigraphic carbonate and more than 97% mag- and the subsequent location of quarries units are present just beneath the uncon- nesium carbonate and calcium carbonate are functions of the configuration of the formity because of beveling by post-Mis- together) like that found at the Thornton Illinois Basin. The basin, as viewed in a sissippian/pre-Pennsylvanian uplift and Quarry in Cook County (Mikulic, 1988) north-south cross section, is roughly erosion (see north-south cross section, spoon-shaped, with the bowl of the spoon Willman et al., 1967). As a result, strata

22 Thickness

in feet (m)

<50(1S) j 1

50-200 (15-61 ]] Pleistocene and Pliocene not shown ^j 200-400 (61-122)

I >400 (122) CRETACEOUS

PENNSYLVANIAN Bond and Mattoon Formations Includes narrow belts of older formations along LaSalle Anticline PENNSYLVANIAN Cartoondale and Modesto Formations PENNSYLVANIAN Caseyvilie, Abbott and Spoon Formations MISSISSIPPIAN Figure 3. Simplified geologic map of surficial, unconsolidated material, Includes Devonian in Hardin County Quaternary and older (from Masters, 1983; after Lineback, 1979, 1981)! OEVONIAN Includes Silurian in Douglas Champaign, and western Rock Island Counties SILURIAN Includes Ordovician and Devonian in Calhoun Greene and Jersey Counties ORDOVICIAN

CAMBRIAN

r^ Des Plames Disturbance—Ordovician to Pennsylvanian Figure 4. Simplified bedrock — geologic map (from Goodwin, 1983- after •^-" Fault Willman and Frye, 1970). that could have been potential targets for considered to be prime markets for ag- glacial drift where the Pennsylvanian is underground mining have been partly or gregate: Bloomington-Normal, Cham- eroded, as in Champaign County. completely eroded in the northern part of paign-Urbana, Decatur, Peoria, and In this paper subsurface stone resour- the study area. Moreover, some carbonate Springfield (fig. 6). This central Illinois ces are discussed in terms of three major units show depositional thinning and/or a area lies within and near the northern "bundles" of predominantly carbonate decrease in quality in more shoreward edge of Pennsylvanian bedrock terrane rock units: in descending order, the Mam- positions. generally overlain by glacial drift of vari- moth Cave, Hunton, and Ottawa Mega- able thickness. Mississippian, Devonian, groups (fig. 7). The underground mining POTENTIAL TARGETS FOR Silurian, and Ordovician carbonate rock potential for each unit is considered in UNDERGROUND MINING units that supply the bulk of the crushed terms of (1) elevation within the study An 11 -county area in central Illinois stone produced elsewhere in Illinois are area with respect to mean sea level, as that produces little or no crushed stone in- preserved in subcrop belts either beneath shown on published structure contour cludes five major downstate urban areas Pennsylvanian bedrock or beneath the maps prepared by the ISGS, and (2) depth

23 of the unit near central Illinois metro- elev politan areas. Depths were calculated from the structure contour data and surface elevations from topographic maps. Surface elevations (fig. 6) generally range from 700 to 850 feet above mean sea level in the eastern part of the study area (Bloomington Ridged Plain) and from 575 to 625 feet above mean sea level h 1000 to the west (Springfield Plain). 4000^ Mammoth Cave Megagroup 5000- Potentially minable carbonates of the

Mammoth Cave Megagroup in central Il- - -2000 linois are essentially restricted to the Ste. Genevieve and St. Louis Limestones of late Valmeyeran (middle Mississippian) L 2500 age (fig. 7). The Mammoth Cave Mega- 60 km group, commonly referred to in subsur- Figure 5. East-west geologic cross section through central Illinois showing the dip of Paleozoic face as the "thick Mississippian lime," strata into the Illinois Basin (Kolata and Nelson, in press). includes limestones and some dolomite.

The Ste. Genevieve is extensively quar- in western Illinois, generally do not meet central Illinois. However, the Dolbee ried along its outcrop in southern Illinois specifications for Class A aggregate be- Creek Member at the base of the Bur- and the St. Louis is quarried in the East cause of softness and/or excessive lington is a high-calcium, soft, crinoidal St. Louis-Alton area and mined under- amounts of chert; they are therefore not limestone mined underground at Quincy ground at East Alton. The Keokuk and prime targets for underground mining in in Adams County; it extends into the sub- Burlington Limestones (fig. 7), quarried surface of the 11-county area. Prelimi- nary study (Cloos and Baxter, 1981) PEORIA indicates mat chert-free limestone assig- I 7 ~i AVOODFORCT nable to the Dolbee Creek is generally ) less than 20 feet thick; however, careful exploration may reveal minable thick- LIVINGSTON I \ "1 MC lean! nesses of chemical-grade limestone at the ^ Peoria base of the Burlington—particularly at /' " some localities in Sangamon County. \ "V — Ste. Genevieve and St. Louis Lime- I Bloomington- stones The Ste. Genevieve and St. Louis / I TAZEWELL Normal Limestones are found beneath Pennsyl- MASON ] Bloomington Ridged Plain vanian strata and beneath Chesterian

( + 700-850 ft) (Upper Mississippian) strata in the south- L \LOGAN \ ern portion of the 11-county area. Figure DE WITT £ V & 8 shows the elevation of the top of the Karnak Member of the Ste. Genevieve {Springfield Plain Limestone, as constructed by Bristol and MENARD h| \ J ( + 575-625 ft) r Howard (1976), and the northern extent \" MACON I of the Ste. Genevieve and St. Louis Lime-

stones. The Ste. Genevieve is charac- SANGAMON terized by oolite that in some places is Springfield ( high-calcium limestone (greater than

S Decatur I 95% CaC03), but some parts of the formation may contain interbedded sand- Approximate boundary f stone or sandy limestone.The St. Louis is LL_. between Bloomington and Springfield Plains predominandy dense, fine-grained limestone, commonly containing light gray to 1 white, high-calcium stone in its upper part. 40 mi Depth to Mammoth Cave Lime- _l stone Megagroup The depth to limestones of the Mammoth Cave Megagroup Figure 6. Eleven-county study area in central Illinois. in the study area is indicated by contours

24 showing the elevation of the top of the Karnak Member of the Ste. Genevieve. The top of the Karnak lies at elevations of more than 800 feet to less than 200 feet below mean sea level in the southern part of the study area, and eroded Mammoth Cave terrane extends even beyond the limits of the St. Louis. Although the physical character of the limestone beds included in the Mammoth Cave Megagroup has not been thoroughly investigated, the top minable beds of "the thick Mississippian lime" may occur at depths of 600 to 800 feet in southwestern Champaign County, 350 to 750 feet in Sangamon County near Springfield, and 800 to 1250 feet in Macon County (about 1100 feet at Decatur). Hunton Megagroup

The Hunton Megagroup includes carbonate rock strata of Silurian through Middle Devonian age. Figure 9 shows the elevation of the top of the Hunton down to the -1000-foot contour line (datum, mean sea level), as constructed by Stevenson and Whiting (1967). Middle Devonian formations Mid- dle Devonian formations in the study area include the Wapsipinicon and Cedar Val-

ley Limestones and equivalent units (fig. 7). On the Sangamon Arch, (southwest corner, fig. 9), rocks of Middle Devonian age were not deposited; the depositional edge of the Cedar Valley overlaps the Wapsipinicon on the flank of the arch, but both units are absent on the crest of the arch.

To the east, in Champaign, Piatt, and Macon Counties, Middle Devonian limestone is present, but beds age-equivalent to the Wapsipinicon display an aspect more characteristic of a deep-water facies prevalent in southern Illinois and are as- signed to the Grand Tower Limestone. North of the Sangamon Arch the Wap- sipinicon is characterized by oolitic limestone, magnesian limestone, dolomite, and evaporites deposited in a semi- restricted to restricted shallow-water environment (James, 1968). In the areas labeled "eroded" (fig. 9), the Middle Devonian has been partly or completely removed by pre-Pennsylvanian erosion (northeast McLean County) or by a combination of pre-Quaternary and pre-Pen- nsylvanian erosional events (northeast Champaign County). Where Devonian strata have been completely removed, un-

Figure 7. Stratigraphic column for central Illinois.

25 derlying Silurian formations are en- fPEORIA ~~f | countered in the subcrop. ^ /woe Silurian formations Silurian rocks present at depth in the study area include ^ / (in descending order) the Racine Forma- tion of Niagaran age, and the Joliet For- mation, which is mostly Niagaran although its lowermost 20 to 25 feet are as- signed to the Alexandrian (fig. 7). The Racine Formation, from which approximately 30 percent of the stone produced in Illinois is won, is the chief target for underground mining within the Hunton Megagroup. The Racine alone is more than 400 feet thick in southern Champaign County, but the entire Nia- garan series is less than 200 feet thick in western Peoria County. Although high- purity, reef-type dolomite has not been reported in central Illinois, the carbonate rocks of Silurian age are predominantly dolomite in the 11 -county area and in locations to the north. In southern Illinois limestone predominates. /" Approximate boundary Depth to Hunton Megagroup The between Bloomington and Springfield Plains depth to carbonate rocks of the Hunton Megagroup can be expected to be less

Figure 8. Elevation of the top of the Karnak Member of the Ste. Genevieve and extent of the Ste. Genevieve (see fig. 6) and the St. Louis Limestones in central Illinois (after Bristol and Howard, 1976.)

than 600 feet in the northwest corner of Peoria County within 15 to 20 miles of Peoria; about 450 feet in northeastern McLean County within 25 miles of Bloomington-Normal, where the Mid- dle Devonian is eroded and the uppermost Hunton unit below the Pennsyl- vanian is the Silurian Racine Formation; and as shallow as 375 feet near Cham- paign-Urbana. Ottawa Megagroup The Ottawa Megagroup comprises formations of the Galena and Platteville Groups (fig. 7, 10). Of these, the Wise Lake and Dunleith Formations at the top of the Galena (top of Ottawa Mega- group) are composed of high-purity f Approximate boundary dolomite in much of the outcrop area in between Bloomington and Springfield Plains northern Illinois. They are mined under-

Extent and thickness (ft)

of Middle Devonian Limestone Flgure 9. Elevation (ft) of the top of the Hun- ton Megagroup, extent of middle Devonian 0-40 40 mi strata, and thickness of the Wapsicinicon and _l : 40-80 Cedar Valley Limestones in central Illinois U. 1 (after Stevenson and Whting, 1 967; Willman et

al., 1975). Arrows along 1000 ft contour show downdip direction. r southern facies f *I- :V -v -V" -"-I

26 ground at Elmhurst in Du Page County, where a high-quality aggregate is produced. The elevation of the top of the Ottawa Megagroup (Bristol and Buschbach, 1973) is shown in figure 10. The Wise Lake and Dunleith were penetrated in a diamond-drill core hole located near For- rest, in Livingston County (fig. 10), where they are predominantly limestone and contain minable thicknesses of high- calcium limestone (Baxter, 1964). The Galena and underlying Platteville are known to grade laterally from limestone

in the south to dolomite in the north in Il- linois. This transition, with respect to the total Ottawa Megagroup, takes place within the 11 -county area (fig. 10); however, the precise character of the limestone-to-dolomite transitions within the Galena and Platteville Groups individually has not been accurately determined. The Galena—the top of the Ottawa Megagroup—occurs at depths calculated to be as shallow as 1175 feet within 20 miles of Champaign-Urbana. However, this location is on a structure that is now the site of a natural gas storage project, and the availability of the Ordovician

subsurface for underground mining is, at best, questionable. The top of the Galena

lies at a similar depth in the northeastern Figure 10. Elevation (ft) of the top of the Ottawa Megagroup (top of the Galena Group) in Central corner of McLean County near Bloom- Illinois (see fig. 6) (after Bristol and Buschbach, 1973). ington-Normal and is perhaps as shallow as 1000 feet northwest of Peoria. the availability of underground sites quired for use in flue gas desulfurization, nearer the market area than potential sur- fluidized-bed combustion technology, FACTORS FAVORING face sites are; an opportunity to negotiate and other chemical and industrial proces- UNDERGROUND MINING a royalty lease as opposed to incurring a ses. Such products demand premium According to Loofbourow (1983), a large acquisition cost; uniformly mild un- prices, and the ability to produce a chemi- combination of favorable conditions is derground working conditions; and sub- cal-grade stone in addition to high- needed to support underground mining sequent use of the underground space quality aggregate near the major central operations: created by mining. Although space acces- Dlinois markets would increase the odds • sible only a rather stable market of at least by means of vertical shafts for the success of an underground mining moderate size would have less potential value for under- operation. • an accessible, large, rather uniform rock ground storage than would space with mass, tending to be dry, in which horizontal access, permanent income REFERENCES sizable, from such stable openings can be made uses as energy accumulation Baxter, J.W., 1964, Chemical composi- • a "kicker" (pumped storage for off-peak generation tion of some deep limestones and of hydroelectricity), disposal, clarifica- Kickers may be factors contributing dolomites in Livingston County, Il- tion of water or air, and other potential linois: to high costs of quarrying stone at or near Illinois State Geological Sur- uses should be considered. vey, the surface within a given market area. Industrial Mineral Notes 23, 5 p. More detailed examination of the They may include high costs associated Baxter, J. W., 1980, Factors favoring ex- depth to minable stone, the chemical with acquisition of land, stripping, waste and panded underground mining of lime- physical characteristics of that stone, disposal, reclamation, or other operation- and stone in Illinois, Mining Engineering, the extent to which the foregoing factors al or environmental problems. On the October 1980, v. 32, no. 10, p. 1497- are operative near central other hand, the operative kicker may be Illinois com- 1504. munities is warranted. some positive factor related to the Bristol, H. M., and T. C. Buschbach, A growing need exists for stone that proposed underground operation, such as 1973, Ordovician Galena Group meets the chemical specifications re- (Trenton) of Illinois—structure and oil

27 fields: Illinois State Geological Sur- Petroleum Geologists, World Report 1987-1; Illinois Dept. of Trans- vey, Illinois Petroleum 99, 35 p. Petroleum Basins Series. portation Project 1HR-416) 84 p. Bristol, H. M. and R. H. Howard, 1976, Lineback, J. A., 1979, Quaternary Mikulic, D. G., 1988, the Chicago stone Structure of the top of the Karnak Deposits of Illinois: Illinois State industry: a historical perspective, (this Limestone Member (Ste. Genevieve) Geological Survey map (scale, volume): Illinois State Geological in Illinois: Illinois State Geological 1:500,000; size, 40 x 56 inches; in Survey, p. 83-89. Survey, Illinois Petroleum 109, p. 5. color). Stevenson, D. L., and L. L. Whiting, Cloos, M., and J. W. Baxter, 1981, Sub- Lineback, J. A., 1981, Quaternary 1967, Geologic structure of the surface variation in the high-calcium deposits of Illinois, Illinois State Devonian-Silurian Hunton Mega- Dolbee Creek Limestone in western Geological Survey map (scale, group in Illinois: Illinois State Illinois: Illinois State Geological Sur- 1:2,500,000; size, 8 1/2x11 inches). Geological Survey, Illinois Petroleum vey Industrial Minerals Note 79, 23 p. Loofbourow, R. L., 1983, Underground 87, 5p. Goodwin, J. H., 1983, Geology of car- mining for aggregate, in Proceedings Willman, H. B., E. Atherton, T. C.

bonate aggregate resources of Illinois, of the 18th Forum on Geology of In- Buschbach, C. Collinson, J. C. Frye,

Illinois State Geological Survey, Il- dustrial Minerals: Indiana Geological M. E. Hopkins, J. A. Lineback, and J. linois Mineral Notes 87, 12 p. Survey, Occasional Paper 37, p. 245- A. Simon, 1975, Handbook of Illinois IDOT, 1986, Sources and producers of 251. Stratigraphy: Illinois State Geological aggregates for highway construction Masters, J. M., 1983, Geology of sand Survey, Bulletin 95, 261p. in Dlinois: Division of Highways, Il- and gravel aggregate resources of Il- Willman, H. B., and J. C. Frye, 1970, linois Department of Transportation, linois, Illinois State Geological Sur- Generalized map of the bedrock sur- Bulletin 23. vey: Illinois Mineral Notes 88, lOp. face of Illinois: Illinois State Geologi- James, A. T., 1968, The Middle Devonian Masters, J. M., 1988, Effects of different cal Survey map (scale, 1:2,500,000; strata of northwestern Illinois and kinds of rocks in Illinois gravels on size, 8 1/2 x 11 inches). southeastern Iowa, Honors thesis: freeze-thaw test beams, (this vol- Willman, H. B., and D. R. Kolata, 1978, College of Liberal Arts and Sciences, ume): Illinois State Geological Sur- The Platteville and Galena Groups in University of Illinois at Urbana- vey, p. 71-81. northern Illinois, Illinois State Champaign, 22 p. Masters, J. M., and R. D. Evans, 1987, Geological Survey, Circular 502, 75p. Kolata, D. R., and J. W. Nelson, in press, Geologic characteristics of Illinois Willman, H. B., et al., 1967, Geologic Tectonic history of the Illinois Basin, gravel deposits affecting IDOT map of Illinois, Illinois State Geologi- in M. W. Leighton, D. R. Kolata, D. F. freeze-thaw test results: Illinois State cal Survey (scale, 1:500,000; size, 40 Oltz, and J. J. Eidel [eds.], Cratonic Geological Survey, Contract/Grant x 56 inches; in color). Basins: American Association of

28 Model of Construction Aggregates Demand and Supply: A Chicago Area Case Study

Subhash B. Bhagwat Illinois State Geological Survey Champaign, Illinois

variations in the reliability of projections, ABSTRACT even for individual regions of states. Al- though statewide models are more Construction aggregates—sand and gravel and stone—represent a $400 mil- desirable, experience has shown that tar- lion industry in Illinois. Because of their low unit value, construction aggregates geting smaller areas are within states may be usually sold within 50 miles of the production site. Local economic conditions more promising. The present investiga- and demographicfactors are thus closely associated with the aggregates industry. tion is the first attempt In in Illinois to model addition, national economic factors and political decisions can influence the the demand for construction construction aggregates. industry and affect aggregates production. Iffuture demandfor ag- The Chicago area is defined here to in- gregates could be successfully predicted, the industry and the economy as a whole clude the six counties of Cook, Du Page, would benefitfrom minimized price fluctuations. Kane, Lake, McHenry, In and Will. This Oregon, Ontario, and California, econometric models were developed to area was selected for study because about predict aggregates production. The results ofthe modeling indicated that regional two-thirds of the Illinois population is conditions differ enough to warrant development of regional models. The inves- concentrated here; about 45 percent lives tigation reported in this paper was the first attempt to develop such a model in Il- in Cook County alone. Currently about linois. Because two-thirds ofthe Illinois population is concentrated in the Chicago 50 percent of the state's stone and sand area, that region was selected as the study area. Econometric models based on and gravel production (excluding in- demographic and economic information on the six counties in the Chicago area dustrial sands) were developed comes from the six-coun- for the projection offuture aggregates production. The models in- ty Chicago area. Most of the dicate that stone used population, employment, gross state product, and mortgage interest in this area comes rates are from quarries in Cook the most significant factors affecting the production of aggregates. and Will Counties (fig. 1); however, sand Short-term projections made with the help of the models were within 5 percent of and gravel actual production pits are widely distributed (fig. figures. However, the statistical reliability of the models is low, 2) (Samson and Masters, and the correlations 1987). Most cannot always be explained logically. Further research is es- stone quarries are in northwestern Illinois sential: detailed community-level data gathering, especially on public construc- counties and most sand and gravel pits are tion projects, could improve the models significantly. A comparison with similar in the attempts central parts of northern Illinois, at modeling in the United States and Canada indicates that the difficul- generally several times ties farther from the encountered in this investigation are not unique to Illinois. Chicago area than are the current sup- pliers to the Chicago area. The most densely populated parts of the Chicago area have few pits or quar- INTRODUCTION for aggregates is a challenging task be- ries because urban sprawl is encroaching Construction aggregates (sand, gravel, cause of the complex factors (at both on existing and potential quarry sites and and stone) are materials of low unit value local and national levels) associated with reserves are becoming depleted (Mikulic that are generally used within 30 to 50 aggregates demand. Yet accurate predic- and Goodwin (1986). If the urban sprawl miles of their places of extraction because tions would enable the industry to continues, construction aggregates may of shipping costs. The demand for these respond quickly and efficiently to chan- have to be transported from greater dis- materials is associated with private and ges in demand and avoid excessive price tances; this could drastically affect public construction and therefore varies fluctuations and shortages. delivered prices and lead to higher con- considerably with location. In addition, Attempts have been made in Oregon, struction costs. The average free-on- the construction industry itself is often Ontario, and California to construct board (f.o.b.) mine value of sand and subject to influences arising from nation- econometric models for projecting future gravel is currently about $2.80 per ton al economic factors such as interest rates demand for aggregates (Friedman, and that of crushed stone is about $4.00 or growth in the gross national product, Niemi, and Whitelaw (1979); Matten per ton. These prices can be virtually and political decisions with respect to (1982); and Stinsen, Manson, and Plap- doubled within 20 miles of the mine site publicly financed construction such as pert (1983). In all cases, modeling on a and tripled at 50- to 60-mile distances national highways or community roads. regional basis was more successful than (fig. 3). Finding ways to predict future demand statewide modeling, and there were wide

29 5

I7SC0TT j

Figure 1 Stone quarries in northern Illinois.

AGGREGATES PRODUCTION Cook and Will Counties produce the most Counties. Urban expansion in these coun- From 1970 through 1984 the produc- stone; Kane and Du Page Counties ties has constrained production; conse- tion of aggregates in the Chicago area produce some stone, and Lake and Mc- quently, future supplies may have to be fluctuated greatly. Recessions in 1972, Henry Counties (fig. 6) produce only neg- shipped from as far as 50 to 80 miles, rep- 1975, and 1982 affected production ligible amounts. resenting a major cost-escalation factor. severely. The downturn in production Accessibility of the available geologic since 1980 has been more severe and has resources has played an important role in DEMOGRAPHICS lasted longer than any other in the past 1 the aggregates industry of the Chicago From 1970 to 1984 the total popula- years (fig. 4). Individual counties differed area. Masters (1978) mapped the sand tion of the six-county Chicago area grew significantly in their production. Mc- and gravel deposits of northeastern Il- steadily from about 6.99 million to about Henry and Kane Counties have been the linois, which are located primarily in Mc- 7.22 million (Office of Real Estate Re- largest producers of sand and gravel. In Henry and Kane Counties. Bradbury search, 1984). This growth occurred out- Will County, sand and gravel production (1977) compiled a map of the dolomite side Cook County; the Cook County declined sharply after 1973 and general- resources in the Chicago area, and his population declined from about 5.50 mil- ly remained as low as production in the map indicates the concentration of lion toabout5.17million. Since 1980the other Chicago area counties (fig. 5). minable stone deposits in Cook and Will population in Cook County appears to

30 Figure 2 Sand and gravel pits in northern Illinois have stabilized at about 5.2 million; the the area depends strongly on demo- federal, state, county, and local govern- outlying counties continue to grow. graphic and economic conditions in Cook ments on roads, highways, and other Employment opportunities in the out- County. public projects are not compiled by any lying counties have drawn people from single agency at the county level. The fol- Cook County as well as counties outside CONSTRUCTION ACTIVITY lowing analysis therefore excludes public the area. Figure 7 indicates the rapid The economic activity linked most construction. The omission presumably employment growth in Du Page County directly with the aggregates industry is distorts Cook County data more than and data continuing high employment in Lake construction, both private and public. from other counties. On the basis of County. na- Figure 8 shows the fluctuating National data on the number of building tional census data, an estimated 10 but to 15 essentially stagnant employment permits issued, construction completed, percent of the total construction activity situation in Cook County. Because of the and value of construction in place are in the Chicago area is publicly financed size of its population, Cook County compiled by the U.S. Bureau of the Cen- and thus not included in the analysis. dominates the employment trend in the sus, which uses a sampling technique The value of private construction in six-county area—a trend showing arising rather than actual data gathering. At a place in the Chicago area (in constant but widely fluctuating employment pat- county level only private construction 1982 dollars) fluctuated between a 1978 tern (fig. 9). Thus, economic activity in data are available. Public expenditures by high of about $4.4 billion and a 1982 low

31 1

50 miles from pit or quarry: - 3.3-4.2 times the pit head price for sand and gravel 2.60-3.25 times the quarry headj price for crushed stone

Probable range

a 30

Figure 4 Production of construction aggre- Figure 7 Employment by county. gates in the Chicago area. Delivered price doubles 6-21 miles from quarry 370

360

13.50

30 60 miles Stone price $4 00 ton FOB quarry

Sand and gravel pit price $2.80/ton FO B 1970 75 80 1984 1970 75 80 Figure Figure 3 Cost of transporting aggregates by 5 County sand and gravel production. Figure 8 Cook County employment. truck. of about $1.3 billion (fig. 10). The 1970- 2 90 1984 trend in construction value in the Chicago area has been downward (about 33%). The downward trend has been most pronounced in Cook County and least noticeable in Du Page County.

FACTORS AFFECTING f970 75 80 AGGREGATES PRODUCTION Figure 6 Stone production by county. 1970 75 80 1984 All sand and gravel and most stone Figure 9 Chicago-area employment. produced in the Chicago area are used in Countywide data on production, the construction industry; therefore, the population, employment, and income following Trend line factors—which significantly were available; however, data on public y = 3.435 -0.0883X affect Std dev = 0.9922 the construction industry in this spending on construction projects in the where x = 1-15 area, also affect the aggregates industry Chicago area were available only for in the Chicago area. highway projects financed or managed by the Illinois Department of Transportation • sand and gravel production (millions of (IDOT). Therefore, the statistical tons per year) analysis for this study was conducted • stone production (millions of tons per without information on non-IDOT public year) 1970 75 80 1984 spending. • value of private residential buildings in Figure 10 Chicago-area construction value. place (billion dollars, 1982) ECONOMETRIC MODEL • value of private nonresidential build- Comparison of figures 4,9,10, and 1 ings in place (billion dollars, 1982) suggest that employment, value of con- • value of public construction projects in struction in place, changes in the GSP, place (billion dollars, 1982) and the real • population (millions) mortgage interest rates may correlated • employment (millions) be with the production of construction in the • personal income (billion dollars, 1982) aggregates Chicago area. Stepwise • inflation-adjusted mortgage interest regression on 1970-1984 data, rates (percent) using a 90 percent confidence level and • year-to-year change in gross state the t-statistic, indicated that total production product (percent) of sand, gravel, and stone was sig- Figure 11 Illinois mortgage rate and GSP nificantly correlated with the value of changes. construction in place and the real mort- 2 gage interest rate (R = 73%, standard

32 Table Statistically significant factors 1 affecting aggregates production in the Chicago area, 1970-1984.

Change Mortgage Model Dependent Population Employment inGSP rate Adjusted Standard Deter- number variable Intercept (million) (%/yr) (%/yr (o/orea ) |) r* error minant

Sand and gravel production (million tons/yr) 377.215 -58.361 15.203 °- 302 — 64.907 1.992 0.568 Stone production (million tons/yr) 23.041 — 0.287 -0.753 63.575 1.902 0.983 Total aggregates production (million tons/yr) 40.553 — 0.628 -1.294 47.163 4.558 0.983

error = 3.26) as in the following and 1986 St°ne and t0tal a re9ates " production in *• Chica9° *™ econometric model: SlonYo?^

Aggregates production = 28.189 + 1985 1986 4.034 (value of private and IDOT- Projected Actual* financed construction) - 0.903 (real Projected Actual* mortgage interest rate) Stone 18.2 17.5 18.8 20.2 The usefulness of this model is Total aggregates 32.5 31.5 35.0 36.4 problematic, however, because values for

construction in •Actual production figures include estimates for place are available only sand and gravel in odd-numbered years and for stone even-numbered after the fact, and estimates are available years. only 6 months in advance. To avoid this est rates have more effect on the con- quality of these aggregate difficulty, attempts were made to con- resources af- struction industry than do such factors as fect their use in struct models without using the value of different types of con- population and employment. Given the struction; therefore, construction in place. The three models different in- negative correlation with population in dependent variables may have resulting from that analysis are presented 2 to be model 1 and the generally low R values, considered in each in table 1. county or region. extreme caution is warranted in using the • The study regions should be These models indicate that individual chosen so models. Researchers in Oregon, Ontario, as to include the centers of economic projections for sand and gravel and stone ac- and California 2 encountered similar dif- tivity and all the major satellite production would be more reliable (R = com- ficulties, which probably stem from inac- munities contributing to that activity. In 64 or 65) than projections of total ag- 2 curacies in available production figures addition, counties supplying construc- gregates production (R = 47); however, and other data, as well as from the lack of tion aggregates to the study regions model 1 cannot be used for sand and detailed data on public construction must also be included. gravel because of the negative correlation projects at all levels of government. between population and production, REFERENCES which cannot be explained without more FUTURE RESEARCH NEEDS Bradbury, J.C., 1977, Dolomite resources research. Models 2 and 3 were used to The results of this pilot study indicate of northeastern Illinois; Report to project for 1985 and 1986 stone and total that the available database is not suffi- Northeastern Illinois Planning Com- aggregates production in the Chicago cient for developing reliable econometric mission: Illinois State Geological Sur- area (table 2). As table 2 indicates, the models for future projections of construc- vey, 16 p. 1985 projected figures are 3 to 4 percent tion aggregates production. To improve Friedman, J.M., E.G. Niemi, and W.E. above actual production figures. By in- results of future studies the following Whitelaw, with the assistance of JJ. ference, sand and gravel production for points should be considered: Gray, 1979, Analysis and forecasts of 1985 can also be estimated as the dif- the demand for rock materials in ference between the two projections in •County-by-county data on public Oregon: Oregon Department of Geol- table 2. The 1986 projections for stone are spending on highways, roads, and other ogy and Mineral Industries, Special 6 percent below U.S. Bureau of Mines facilities must be compiled, and Paper 5, Portland, OR, 84 p. (U.S.B.M.) estimates, and projections of projected spending plans must be avail- Masters, J.M., 1978, Sand and gravel and total aggregates production are 10 per- able. peat resources in northeastern Illinois: cent below U.S.B.M. estimates. As ex- • Usage factors for sand, gravel, and Dlinois State Geological Survey Cir- pected, accuracy of the projections crushed stone must be developed for cular 503, 11 p. declines as attempts are made to project various kinds of construction (e.g., Matten, E.E., 1982, A simplified proce- production farther into the future. homes, office buildings, roads, and dure for forecasting demand for Models 2 and 3 unexpectedly revealed highways) in each county. Geologic occurrence mineral aggregate in Ontario: Minis- that changes in GSP and mortgage inter- (location and depth) and try of Natural Resources, Industrial

33 Mineral Background Paper No. 4, Office of Real Estate Research, College Geological Survey Illinois Mineral Mineral Resources Branch, Ontario, of Commerce and Business Ad- Notes 96, 151 p. Canada, 184 p. ministration, County by county Stinsen, M.C., M.W. Manson, and J J. Mikulic, D.G., and J.H. Goodwin, 1986, demographic and construction value Plappert, under direction of J.F. Davis, Urban encroachment on dolomite data for 1970-1984: computer files, R.G. Strand, and D.J. Beeby, 1983! resources ofthe Chicago area, Illinois, University of Illinois at Urbana- Mineral land classification: Aggregate in Proceedings of the Twentieth Champaign. materials in the San Francisco- Forum on Geology of Industrial Samson, I.E., and J.M. Masters, 1987, Monterey Bay Area: California Minerals, 1984, Baltimore, MD: JJ- Directory of Illinois mineral Department of Conservation, Special linois State Geological Survey Reprint producers 1986-1987: Illinois State Report 146, Division of Mines and 1986G, 7 p. Geology, Sacramento, CA, 50 p.

34 Industrial Sand in Indiana*

Donald D. Carr, Curtis H. Ault, and Todd A. Thompson Indiana Geological Survey Bloomington, Indiana 47405

deposits—the curve will be modified. ABSTRACT The decline in production of a nonferrous-metal deposit is largely due to a About 1900, as the result of rapidly growing foundry and glass industries, In- depletion of ore, but the decline in diana ranked second among the states in industrial-sand consumption. Only production of an industrial minerals about a third of the industrial sand consumed was produced in-state sour- from deposit such as industrial sand is more ces, but these Indiana sources were diverse. They consisted of Silurian sandstone likely to result from other causes. near Logansport, Devonian sandstone near Pendleton, Mississippian sandstone Production of industrial sand in In- near the Ohio River in south-central Indiana, Pennsylvanian sandstone from diana probably followed the typical various places in southwestern Indiana, and Quaternary dune sand near Lake curve: rapid increase in production and Michigan. As specifications various uses for became more stringent, only those then a slow decline. The reason for the operators with high-quality sand or sandstone could compete with out-of-state rapid increase was not a new discovery of sources. Today, industrial sand is produced in Warren, Porter, andLaPorte Coun- industrial sand but the discovery of a tiesforfoundry use and in Harrison Countyfor glass, chemical, and miscellaneous cheap source of locally available fuel that uses. permitted the growth of industries using Sand with a high-silica contentfrom the Bethel Formation (Mississippian) in industrial sand. And the reason for the southeastern Indiana has been used intermittently since the late 19th centuryfor decline was not the depletion of deposits glass,foundry,filter, and other uses. In 1985, the CARD Industrial Sand Corpora- but the new, rigid specifications being set tion built a new processing plant near New Albany at the site formerly occupied by the glass manufacturers and foundries by the Indiana Glass Sand Company and the River Ohio Silica Corporation. This that put producers of inferior industrial new operation mines hydraulically and pumps the sand slurry about a quarter of sands out of business. a mile to a processing area with a deslimer, attrition mill, and hydrosizer. After air This paper includes a brief history of drying, the sized sand is further dried in a rotary lain. The attrition mill removes industrial-sand production in Indiana, a a large part of the iron oxide coating on the sand grains and provides a silica review of the geology of sands suitable product with a Fe203 content about 0.025 of percent. The main industrial-sand for industrial purposes, and a discussion marketsfor this product are within 200 miles ofNew Albany. of the new CARD Industrial Sand Cor- poration plant near Elizabeth, which seems destined to change INTRODUCTION the industrial- This hypothetical example applies sand production curve for Indiana. Indiana has had a flourishing in- when price, demand, and other variables dustrial-sand industry. If we could plot are constant; however, if either the price PRODUCTION HISTORY production of the state's industrial sand or demand changes—for instance, be- The most abrupt sociologic and through time (which is impossible because of a war or the discovery of new economic change that has occurred in the cause of inadequate records), our curve state began in 1886, when gas was dis- would probably approximate the curve covered in the Trenton Limestone (Or- traditionally shown for the production of dovician) in northeastern Indiana. This anonferrous-metal deposit (fig. 1). In this discovery of oil and gas in the Trenton hypothetical example, the number of Field—two years after oil had been dis- mines, or production, of a nonferrous covered in the Lima field in Ohio—was metal goes through a youthful phase of the beginning of the petroleum industry rapid development following initial dis- in Indiana. The Trenton Field was among covery. Production stabilizes during the the largest fields of its time, and even by mature stage and then declines slowly today's standards its areal extent ranks it through an old-age phase until the deposit Time as one of the giant fields in the world. The is depleted or until the grade of the ore is shallow Figure 1 The life cycle of a nonferrous-metal depth of the gas-producing zone too low to be economically produced. deposit (modified from Peters, 1966, and Skin- (less than 1000 feet) and the low drilling ner, 1979). and completion costs brought a rapid in-

This paper includes information pertaining to CARD Industrial Sand Corporation and industrial sand in Indiana in 1987 at the time the 23rd Forum on the Geol- ogy of Industrial Minerals was held. The plant CARD has since closed its operation. The reason for its closing is unknown.

35 Foundry sands were also in demand at the turn of the century. Specifications for foundry sands were less stringent than 30 those for glass manufacture, and foundry sands were produced in as many as 36 counties (Logan, 1922); however, by 1918 only 20 27 counties were producing foundry sands (fig. 4). In 1926, Indiana ranked second among states in molding- sand production (Logan, 1930). Just as happened in the glass industry, the loss of an inexpensive source of fuel and an increase in restrictive specifications for foundry sand caused ll|llll|illi| a decline in the num- lll|ll.i|iiii|.. ., ber of producers. In 1890 1900 1910 1920 1987, only Fountain, 1930 1940 1960 1970 1980 Harrison, Porter, and Figure Estimated gas LaPorte Counties 2 production in Indiana, 1886-1973; all production for 1886-1915 is from had foundry-type the Trenton Field (from Carpenter and others, 1975). sand production. The U.S. Bureau of Mines reported crease in production (fig. 2). But with despite these diverse sources, Indiana that in 1986 about 190,000 tons of in- cheap costs came rapid and uncontrolled producers supplied only one-third of the dustrial sand, valued at $1.3 million, was development. state's needs. The heyday of glass-sand produced in Indiana. Most Current sand people in Indiana seemed to be- production was shortlived. By 1987 only production comes from Manley Brothers lieve that gas supplies were unlimited, Harrison County in southern Indiana was of Indiana, Crisman Sand Company, Har- and it was not uncommon for wells to go producing glass sand. rison Steel Castings Company, and uncapped or be burned in giant flam- beaus. Some towns used gas for street lights, and some cities, to entice industry from the east to Indiana, advertised in newspapers that gas was free. These in- ducements led to an influx of diverse industries, and the glass and foundries industries created a large demand for industrial sand. The lack of understanding of reservoir properties and the absence of a central- ized regulatory body to control drilling and production practices led to widespread resource waste and depletion. The production of Trenton gas declined rapidly after 1902. The production curve for Trenton gas and the production curve for industrial sand in Indiana have a similar configuration, which indicates a close relationship between them. As the source of low-cost fuel became rapidly depleted and foundries and glassworks closed, the demand for sand declined. The rigid specifications imposed by the foundries and glassworks that remained in business further reduced the demand for sand. At the turn of the century, Indiana ranked second in the nation in glass production with 71 glassworks in operation (Burchard, 1907). With such a demand for glass sand, many local sources were tried and many, although inferior by today's standards, were used. Before 1922, sand for Figure Indiana glass manufacture 3 counties that produced glass sand before 1922 (data from Burchard, 1907; was produced in ten counties (fig. 3), but Barrett, 1914; and Logan, 1922).

36 i I

CARD Industrial Sand Corporation (fig. Manley Brothers of Indiana (Toleston 5). Manley Brothers and Crisman are Beach) (fig. 6). mining Quaternary dune sands, and Har- The Calumet Beach began to form rison Steel Castings and CARD are about 11,800 years BP (Hansel et al., producing from Paleozoic sandstones of 1985) at about 30 feet above current lake fluvial and submarine-channel origins. level (580 feet). This lake phase was established at an altitude of 610 feet above GEOLOGY AND CURRENT mean sea level following transgression of PRODUCTION OF DEPOSITS the southern shore of ancestral Lake Quaternary sand Michigan. The supply of sediment to the Although unconsolidated deposits of southern shore of Lake Michigan was sand and gravel are abundant throughout great enough to cause progradation of the northern Indiana, sands suitable for in- shoreline and stacking of nearshore sedi- dustrial purposes are less well distributed. ments over deeper water deposits The most abundant accumulations occur (Thompson, 1987). Therefore, the dune in northwestern Indiana as dune deposits sands are in the upper and landward part in several ancestral beach ridges along of the dune and beach complex and com- Lake Michigan. The two most lakeward monly overlie beach sand and gravel. complexes of dune and beach sediments, The Toleston Beach began to form the Calumet and Toleston Beaches, have about 7000 years ago at the end of the been mined for industrial purposes and next large-scale rise in lake level (Hansel are currently being mined by Crisman et al., 1985), when the lake level stabi- Sand Company (Calumet Beach) and lized at about 600 feet. Throughout its history, the Toleston shoreline has \\\N Pennsylvanian

Mississippian iagrang'eR^^V

'/•'//] Silurian and Devonian

MPS»^ y//\ Ordovician I

• Unconsolidated deposits

+ Bedrock deposits

,_J Southern limit ot glacial deposits H /; i ^sS FgranWNGRANTN i— Figure 5 Locations of plants producing in- rfippECANOE ~ r i R\^\nT dustrial sand in 1 987, and major bedrock units *8§^---\ ^^_._ j in Indiana. •>A^Lafavette — [ iMunciel I ^j j

prograded in the western part of the In- kHENRY^r -

5^" diana Dunes and has produced more than TrsY , ~£oO\\Richmond| Mndianapohs ^s^ 100 low-relief beach ridges in the Gary and Hammond areas. The Toleston shoreline in the eastern part of the Indiana Dunes has remained relatively stable, and therefore a thick sequence of dune deposits has formed on top of the early Toleston Beach deposits in the Michigan

City area (Thompson, 1987) (fig. 6). In the eastern dune area, the elevation of the tops of the Toleston and Calumet dunes is about the same, although the Toleston dunes are more extensive. The dune sands are fine grained, well rounded, and moderately to very well sorted (fig. 7). Commonly, a sequence of 30 Miles r i dune sands fines slightly upward. In i— —— 50 Km general, the Toleston dune sands are slightly finer grained than the Calumet Figure 4 Indiana counties that produced foundry sand in 1918 (data dune sands. from Logan, 1922).

37 —

it is discharged to large conical piles for air drying; further drying is by kiln. The

sand is transported by both truck and rail. The product is used for various foundry purposes.

Pennsy I vanian sandstones oChesterton LaPorte, ' About one-third of the Pennsylvanian "Gar^ CRISMAN rocks in the Illinois Basin are sandstones, SAND CO. LA PORTE Portage and several of these sandstones have potential for use as industrial sand (Mur- PORTER ray and Patton, 1953; Carr, 1971). Those most widely mined in Indiana are LAKE sandstones of the Mansfield Formation "Valparaiso the lowermost Pennsylvanian formation in Indiana—which crop out at the surface

5 Miles from Warren County to the Ohio River.

' ' I i'i i 'i'i They have been used for refractory brick, 5 Km glass, and foundry purposes, but are cur- Figure Major sand rently 6 deposits in northwestern Indiana and locations of operations of the Manley being used only for foundry sand. Brothers of Indiana (Toleston Beach) and the Crisman Sand Company (Calumet Beach). The thickest Mansfield sandstones are fine to medium grained and Dune sands are composed of more are fairly well Sand sorted (fig. but relatively than 90 percent quartz in many places 8), pure coarse- Cs Med grained sandstones and pebble con- (table 1), but in some places 25 percent of glomerates are found in the sand may consist of feldspar and places. The crossbeds are thick and dip unimodally heavy minerals. The compositional varia- toward the southwest, tions of the sand fraction among beach indicating the al- 60- luvial origin of the sandstones complexes is not great. Sand produced by (Potter, 1963). the Crisman Sand Company has a rela- The composition of 48 samples of tively high clay content, which gives it Mansfield sandstones natural molding-sand characteristics. averaged 96 percent silica (table 1). Carbonate This sand is older than the material minerals 40- are few to nonexistent produced by Manley Brothers, which in the Mansfield. Silica content can be increased by run- may explain its higher silt and clay con- ning the sand through a log tent. The Calumet sand produced by Cris- washer to remove the clay and silt. man has had a longer time to develop a The Harrison Steel Castings Company 20 soil profile, and the soil probably con- quarries Mansfield sandstone tributes to the clay content of the dune. for its own uses as foundry sand. The sandstone is The Crisman Sand Company is a small mined in two benches, each corporation that mines by front-end about 12 feet high, by drilling and loader and ships both bulk and bagged blasting. The sand is rrrrm, carried by front-end loader to the plant, products by truck. The product is used 590 420 where it is crushed and sieved mainly as a blast-furnace runner sand. to pass a 3/16-inch screen. The oversize is dis- Manley Brothers is owned by British In- Figure 7 Histogram showing size distribution carded. The sand is sized by dustrial Sand. The sand is hydraulically a wet clas- of Quaternary sands in northwestern Indiana mined and sifier and blended with appropriate and number of samples analyzed. pumped to large towers, where binders for use in the foundry. Table 1 Chemical analyses of Quaternary sands and Mansfield and Bethel Sandstones. Mississippian sandstones

Mississippian sandstones used for in- Average chemical analyses content (%) dustrial sand are restricted to those of the Deposits Si02 Al Fe Chesterian Series. Sandstones of the 2 3 2 3 CaC03 MgC03 Chesterian constitute about 25 percent of Dune Sand, the total 91.9 3.80 0.53 2.5 0.9 Chesterian section (Potter, Manley Brothers 1963). Although several of these Dune Sand, sandstones have potential for use as in- 86.7 5.00 1.40 5.3 1.7 Crisman Sand Co. dustrial sand, sandstones of the Bethel Formation in south-central Mansfield Sandstones Indiana have 96.3 2.60 0.66 0.1 0.1 been most extensively used for this pur- Bethel Sandstones 97.8 1.42 0.39 0.1 0.1 pose.

38 Reelsville Ls. is subject to rapid erosion (in places a miniature Sample Fm. "badlands" topography develops). The sandstone is generally 40 Beaver Bend Ls. to 50 feet thick but is 80 feet thick in places in Harrison Bethel Fm. County. It is fine to medium grained and moderately well sorted (fig. 11), and the sand grains are Paoli Ls. round to angular and poorly cemented. Most of the iron oxide in the sand occurs as a film around individual grains. Analyses of more than 30 samples indicate an average silica content of 97.8 per-

cent (table 1) and a clay content of 1 to 2 percent. There are few carbonate Ste Genevieve Ls. minerals.

250 177 149 In 1985, CARD Industrial Sand built Size (mm) a new processing plant near Elizabeth at the site Figure 8 Histogram showing size distribution of a former operation (built in of a sample of Mansfield sandstone collected 1964) that was known as the Indiana from the quarry of the Harrison Steel Castings Glass Sand Company. Indiana Glass Company and number of samples analyzed. Sand operated until the early 1970s, when it was sold to the Ottawa Silica Company. The name of the plant was changed to the Ohio River Silica Company and the plant St. Louis Ls. was operated until about 1976, when it became inactive until rebuilt by CARD. At the CARD operation the sand is mined hydraulically, pumped to temporary storage, and then processed through a deslimer (log washer) to Salem Ls. remove the clay, silt, and very fine sand fraction (fig. 12). The sand is next Figure 10 Stratigraphic section of rocks of Mis- processed through an attrition mill to sissippian age showing relationships of the remove iron oxide coatings from the Bethel Formation to underlying and overlying sand rocks in south-central and western Kentucky. grains and then through a hydrosizer to After Sedimentation Seminar, 1969. separate out the very coarse sand from the medium- and fine-sand fraction. The marine-channel fill system that extended waste from the deslimer and attrition mill southward from Indiana into Kentucky. Sand In Kentucky this sand has been called the Tip Top Sand and the Bethel Formation. 10 Km The term "Bethel" is now used mostly for Figure 9 Distribution of Bethel sandstones this sand body in both Indiana along the Norman Upland. and Ken- tucky. The sand has been mined for many Scattered deposits of poorly con- industrial uses in several places, mainly solidated sands forming a linear pattern Washington, Harrison, and Floyd Coun- in areas of the Norman Upland of ties; it is mined now in only one location, Washington, Clark, Floyd, and Harrison near Elizabeth in Harrison County. Counties (fig. 9) were called the Ohio In southern Indiana, the Bethel sand River Formation in 1903 (Ashley and deposits lie on the Salem and St. Louis Kindle, 1903). Historical evidence indi- Limestones (Mississippian), but as the cates that the deposits have been mined sandstone body is traced south into Ken- for some time; they were being used to tucky the sand occupies positions higher supply a plate-glass operation in New Al- in the section (fig. 10). About 25 miles 250 177 149 105 bany in 1874. south of the Ohio River in Kentucky, the Various Size (mm) theories have been proposed normal stratigraphic sequence is found to explain the origin of the sand deposits where the Bethel overlies the Paoli Lime- Figure 11 Histogram showing size distribution (Wayne, 1960). A study published in 1969 stone. of samples of Bethel sandstones from Washington, (Sedimentation Seminar) interpreted the The sandstone is white to brownish Harrison, and Floyd Counties and sands as remnants of number of samples analyzed. an extensive sub- red, and because of poor consolidation it

39 diana: Indiana Geological Survey Bul- SAND PIT , letin 42-N, 57 p. ATTRITION DESLIMER HYDROSIZER Carr, D. D„ 1971, Specialty sand resour- MILL ces of Indiana: Indiana Geological

Survey Bulletin 42-F, 30 p. Hansel, A. K., D. M. Michelson, A. F Schneider, and C. E. Larsen, 1985, Late Wisconsinan and Holocene history of the Lake Michigan basin: TAILINGS STORAGE PONO DRYER Geological Association of Canada Special Paper 30, p. 39-53. Logan, W. N., 1922, Economic geology of Indiana, in Handbook of Indiana Figure 12 Steps used by the CARD Industrial Sand Company to process Bethel sandstone near geology: Indiana Department Elizabeth, Harrison County. of Con- servation Publication 21, pt. 5, p. 571- is carried to a tailings pond for disposal, sylvanian sandstones in southwestern In- 1058. and the processed sand is taken to stock- diana should continue to serve local Logan, W. N., 1930, The foundry sands piles for air drying. In the final step of markets, production costs will make of Indiana: Indiana Department of processing, the sand is dried in a rotary these sands less attractive in larger Conservation Publication 92, 8 p. kiln and stored in silos. markets. The Bethel sandstones in south- Murray, H. H., and J. B. Patton, 1953, Although the sand processing is central Indiana are high in quality, are lo- Preliminary report on high-silica sand simple, it is effective. By removing the cated close to markets, and can be in Indiana: Indiana Geological Survey fine clay and silt fraction in the log produced competitively. The CARD In- Report of Progress 5, 35 p. washers and the iron oxide coating on dustrial Sand operation has added a Peters, W. C, 1966, The role of the grains in the attrition mills, final a product youthful phase to an otherwise old-age geologist in the life cycle of a mine: can be obtained.The sand has characteris- industry in Indiana. Journal of Geological Education, v. tics that make it suitable for many in- 14, p. 191-193. dustrial uses; it is currently being ACKNOWLEDGMENTS Potter, P. E., 1963, Late Paleozoic produced for foundry, glass, stone appreciate the We help and friendly sandstones of the Dlinois Basin: Il- sawing, abrasives, and chemical uses. cooperation of Frederick C. Ward, CARD linois State Geological Survey Report Industrial-sand deposits are typical of Industrial Sand Corporation; Edwin of Investigations 217, 92 p. industrial-minerals deposits whose Nicholson, Crisman Sand Company; and Sedimentation Seminar, 1969, Bethel market value depends largely on the loca- Butch Swift, Harrison Steel Castings Sandstone (Mississippian) of western tion of the deposit. Although specifica- Company. Kentucky and south-central Indiana, a tions for industrial sand are very precise, submarine-channel fill: Kentucky sand is still bulky, heavy, and expensive REFERENCES Geological Survey Report of Inves- to transport. The operation faces Ashley, G. H., E. CARD and M. Kindle, 1903, tigations 11, 24 p. competition from companies The geology the producing of Lower Carbonifer- Skinner, B. J., 1979, Earth resources, in silica sand in the surrounding states of D- ous area of southern Indiana: Indiana Proceedings of the National Academy linois, Michigan, and Ohio, but the Department of Geology Natural and of Sciences USA: v. 76, no. 9, p. 4212- quality of the sand, location of the Resources Annual Report 27, p. 49- 4217. deposit, and favorable production costs 122. Thompson, T A., 1987, Sedimentology, allow the company to be competitive Barrett, E., 1914, Glass sands of In- internal architecture, and depositional within about 200 miles of its plant near diana—industries: Indiana Depart- history of the Indiana Dunes National New Albany. ment of Geology and Natural Re- Lakeshore and State Park: Ph.D. sources Annual Report 38, p. 41-59. thesis, Bloomington, Indiana Univer- SUMMARY Burchard, E. F, 1907, Glass-sand in- sity, 295 p. Production of Quaternary dune sands dustry of Indiana, Kentucky, and Wayne, W J., 1960, Stratigraphy of the in northern Indiana is limited because of Ohio: U.S. Geological Survey Bul- Ohio River Formation: Indiana restrictive land uses and strong competi- letin 315, p. 361-376. Geological Survey Bulletin 21, 44 p. tion from nearby producers in Illinois and Carpenter, G. L., T. A. Dawson, and S. J. Michigan. Although production of Penn- Keller, 1975, Petroleum industry in In-

40 Depositional Environments of Natural-Aggregate Reserves, Osseo District, Twin Cities Metropolitan Area, Minnesota

Rudolph K. Hoagberg R. K. Hoagberg Associates, Incorporated 1409 Willow Street Minneapolis, Minnesota 55403

ABSTRACT

Gravel-bearing sand (natural aggregate) has been minedfrom the Osseo district for about 45 years, and it seems likely that production from the district will continue to the year 2000 and beyond. In map view, the natural-aggregate bodies occur as regularly spaced, single to OSSEO compound pods ranging 5 to 80 acres in area. from In vertical section the bodies DISTRICT are from 35 to 80 feet thick, changing downgradient from rod shaped to lens shaped. They are composed of a series of tabular, gravel-rich sand layers 1 to 10 feet thick, containing gravel particles in imbricate structures. They are underlain by sandy to silty clay lacustrine sediments, have steep, saw-toothed interfaces with either sandy or silty clay lacustrine sediments or sand or sandy loam diamict sediments and are overlain by 5- to 25 -foot-thick layers ofsand to sandy loam diamict and/or silty sand lacustrine sediments. During its meltback in late Wisconsinan time, the Des Moines Lobe, St. Croixan Association glacier ice reached a series of stillstands at high points within the Osseo district. During ice melting at each of the stillstands, meltwater streams carried freed rock materials from upgradient regimes within tunnels and open channels to the highly fractured, lobate ice margin where, depending upon the Figure 1 Location map, Osseo district, Min- amount of head loss, they were deposited as stream-channel and asfan and lake- neapolis-St. Paul (Twin Cities) metropolitan floor fades within an ice-front, glacial lake. Episodically,for considerable lengths area. time, of high-volume meltwater flows (from superglacial lakes) carried, as bed- load and by saltation, pebble-, cobble-, and minor boulder-size rock particles and percent other deposited them sedimentary rocks. The ag- as tunnel/channel and proximal deltaic eskerine fades. In later gregate materials stages contain less than 1.0 of meltback, meltwater streams eroded deep channels in the natural-ag- percent gregate shale and less than 0.2 percent bodies andfilled them with distal, gravel-poor channel-fades sands. chert; their mean Los Angeles Rattler Shallowly underlying the St. Croixan natural-aggregate bodies are pre-late (LAR) Wisconsinan value is 14.8. natural-aggregate bodies that were probablyformed within depositional environments similar to those describedfor the St. Croixan bodies. Procedures

The stratigraphy of the natural-aggregate and bounding glacial sediments was determined from pit-bank examina- INTRODUCTION struction boom that followed the War. As tions and drilling information on the 150- Location and extent many as 30 operators were active in the acre client property (fig. 2). Drilling The Osseo natural-aggregate mining district in the late 1940s; currendy there information consisted of descriptions of district encompasses about 1800 acres in are five commercial operations in the dis- the sediment returns from, and rate of bit the northwest part of the Twin Cities trict and two other operations managed penetration within, 13 auger borings (fig. metropolitan area in Minnesota (fig. 1). by state and local government agencies. 3); each was 4 inches in diameter and 50 The district is readily accessible from the to 80 feet deep. Quality of the aggregate metropolitan freeway network. We utilized previously gathered pit- The physicochemical quality of the bank Production history descriptions and subsurface data for aggregate materials from the Osseo dis- a reconnaissance study of the district. In Natural aggregates have been pro- trict is very high. The coarse-aggregate addition, vertical, black and white aerial duced from 33 pits, ranging from 5 to 65 particles (+2 mm particles) have a photographs (scale, 1:20,000) were acres in size, within the Osseo district lithologic composition (Meyer and Jirsa, viewed stereoscopically to determine the (fig. 2). Production began before World 1984) of about 60 percent crystalline limits of the active, active-on-demand War n but accelerated during the con- rocks, 17 percent carbonate rocks, and 22 and abandoned pits. Trends of topo-

41 ridges or the southwest part of the client Client Property pits property, and shows the sequence and type of natural-aggregate materials and

, crevasse traces / their relationships to bounding glacial sediments.

... v - >^,^ . mmf The sediments depicted in figure 4 were deposited from two late-Wiscon- 7^ !\ sinan Stage (Hobbs and Goebel, 1982) glaciers. All but the capping sediments water are of the St. Croixan moraine association „ Jt V\ A of the Superior lobe (less than 20,500 years BP, Wright, 1972). The capping diamicton and lacustrine sediments are of -v (V, «b the Pine Citian moraine association of the Des Moines lobe, the youngest of the Wisconsinan glacial lobes to advance vJ into the Twin Cities lowland (Wright, ^\^b / 1972). About 200 to 300 feet of pre-Su- 4 7 perior lobe glacial sediments underlie the ^»j St. Croixan sediments and overlie an \ V I erosional surface developed upon the

Figure 3 Topographic and boring-location map of southwest part of client property, Osseo district.

42 rme Utian

i diamicton sediments St Croixan 12 Pine Citian diamicton sediments * « lacustrine sediments 1 >c '^^^ k •8'-- < Z: ?^t

^^<*. p. • * 3"' f » eskf eskf V/-V eskf Idf ^B — *v * "^ * < • An '

--' —

e°-5~ — eskf-'?'-, > s

St. Croixan lacustrin n sediments 20-i

St. Croixan meltwater sediments: eskf eskerinefacies

Idf lateral/distal facies 100 200 ft

Figure 4 Longitudinal vertical stratigraphic section through southeast-trending natural-aggregate ridges, southwest part of client property, Osseo district.

terpreted to be of fan- and lake-floor Diamicton The St. Croixan diamic- subangular to well-rounded sand and facies, range from sandy loam to silty ton sediments bound the sides and thinly minor amounts of silty sand and sandy loam (after USDA, in Hunt, 1972, p. 226) overlie the natural-aggregate bodies (fig. loam. —i.e., mostly of medium-size sand 4). The diamicton sediment sequence, within a matrix of 5 to 15 percent silt- to commonly overlain by a thick residuum DEPOSITIONAL ENVIRONMENT clay-size mineral and rock particles. Peb- of loamy sand and sandy loam, ranges in Overview ble-bearing dropstone layers interrupt the thickness from 2 to 25 feet and is com- The following description of the lacustrine sequences in some localities. posed of pebble-bearing, loamy sand to depositional environments of the natural St. natural- Meltwater The Croixan sandy-clay loam. The diamicton sedi- aggregate bodies is based on detailed ex- aggregate bodies (meltwater sediments) ments near land surface (less than 7.5 feet aminations of the 8.3-acre client tract and the beneath southwest client property deep) are flow till (Drewery, 1986)—i.e., reconnaissance examinations of the rest (figs. 3, are from 23 to 75 feet thick and formed the 4) by direct accumulations of of the Osseo district. A series of stillstand from 300 to 1500 feet wide and extend sediments from the glacier ice and some- zones formed during the retreat of the St. from to 1750 feet in southeasterly 500 a what modified by gravitational and/or Croixan glacier-ice margin. (A stillstand direction. In vertical section, the bodies water transportation. The lower part of may be defined as an equilibrium condi- display 10° 25° to sawtoothed inter- the sequence is of melt-out till common- tion in the flow of a glacier-ice lobe fingerings with the bounding St. Croixan ly having pebble layers from 5 to 7.5 feet during which the rate of ice melting ap- glacial sediments, diamictons. mostly In apart. proximately equals the rate of advance.) view, map the bodies consist of either a Pine-Citian A cover of Pine Citian The stillstand zones that developed single layer or a complex of teardrop- moraine association diamicton and during the retreat of the St. Croixan shaped, pebble- to cobble- to rarely lacustrine sediments overlies the St. glacier ice are interpreted, on the basis of boulder-bearing sand layers, herein Croixan sediments (fig. 4). The thickness land-surface exposures, to have been termed facies eskerine- sediments. Al- of the Pine Citian sediments of the south- similar to those that developed during the though most of the gravel-rich layers are west part of the client property ranges retreat of the Des Moines lobe along the matrix supported, clast-supported layers from about 5 feet in the eastern part to St. Croix moraine (Hoagberg, 1980) in an also occur. The layers dip and trend from more than 15 feet in the part. western The area about 1 5 miles to the southeast of the N60°E to N70°E. diamicton sediments (melt-out till) con- Osseo district. Sparsely pebble-bearing valley-fill sist mostly of sandy loam to loam with Three lobate stillstand zones (south- sand bodies cross-cut the natural-ag- subangular to well-rounded, pebble- to east, medial, and northwest) formed gregate bodies (fig. 4). These sandy cobble-size rock fragments. Lacustrine during the retreat of the St. Croixan materials (lateral/distal facies) extend sediments to 12 feet up thick are found glacier ice from the Osseo district (fig. 2). generally southwesterly for distances within lowlands between the natural-ag- As indicated by the fissure traces or greater than 1500 feet. gregate ridges. They consist mostly of crevasses shown on figure 2, the natural-

43 aggregate deposits are found within Steep-crested eskers The steep- Lacustrine bodies that radiate sediments out from a series of crested eskerine sediment bodies (fig. 6), Upon stillstands that occurred within each entering the ice-front glacial such as those in the southeast client zone. Meltwater streams having lakes, the coarse-sediment load of widely property within the northwest the stillstand meltwater varying rates of flow carried and flows was deposited in the zone, were probably formed in steep- deposited the proximal reaches of open natural-aggregate materials sided, cathedral-shaped channel/deltas ice channelways because within ice-tunnel or open channels of sudden dissipation in flow. The developed within the ice fissures fine-sediment load was carried just up crevasses by the overflows, interflows, hydraulic gradient from the glacial ice and underflows until margins. lake surface deposited in lacustrine fans and in a variety of other basin-margin Stillstand zones and basin- floor facies. The three stillstand zones shown on figure were 2 delineated by differences in SUMMARY the general pattern of the aligned depres- On the basis of the study findings, we sions (fissure traces) on the Osseo quad- suggest that the depositional controls for rangle topographic map. the eskerine and natural-aggregate Within the southeast stillstand zone lacustrine-fan sediments of the southeast the fissure traces are somewhat radial in stillstand zone were deposited peri- plan, but nevertheless oriented south- odically within the broad ice-tunnel Figure 5 Diagram of a multiple, coalescing chan- easterly. The fissure traces of the south- nelways tunnel-esker depositional environment that developed within fissures east and medial zones are more widely (modified from Rust and Romanelli, ig75). perpendicular to the glacier-ice margin. spaced than those of the northeast zone The brief periods of stream flows within (see fig. 2). these channelways were generally (fig. at On the basis of research findings on 6) positions more distal than the moderate to low because of the cyclic the hydrology and sedimentation broad-crested bodies; they were proba- of freezing and thawing of the glacier bly formed during ice. present-day glaciers we can hypothesize large-volume flows Within the medial stillstand zone, the depositional over relativly short time intervals (LeB. environments that ex- cyclic freezing of meltwater Hook, Wold, stream net- isted within stillstand zones during and Hagen, 1985). The the works within the adjacent glacier rocks that ice retreat of the late St. Croixan had been entrained in the glacier ice resulted in moderate to low stream-flows glacier ice from what is now called the Osseo adjacent to the channelways dis- and the development of broad-tunnel trict were carried mostly as bed load, by the channelways. Consequently, the relatively high major Two general types of eskerine, stream flows. Deposition depositional mode was that of broad- within relatively short, natural-aggregate bodies, broad crested steep-sided chan- crested, gravel-bearing eskerine deposits. and steep nelways probably resulted in generally crested, are found within the Within the northwest poorly stillstand zone, district. Both types sorted, poorly bedded eskerine reflect the shapes of the occurrence of closely spaced the conduits (tunnels sediments, whereas deposition within the or open channels) southeast-trending fissures longer in the glacier- that developed along ice fissures channelways resulted in well- near gla- ice margin is reflected in the abundant sorted, well-bedded, cial ice margin. Most bodies were eskerine sediments. sharp-crested As would eskerine, natural-ag- deposited within fissures perpendicular be expected, the sediments gregate-rich ridges. The occurrence of to the local flow deposited in either of the depositional en- direction of the glacier abundant gravel-size rock vironments particles ice; some crosscutting bodies, mentioned reflect the coarse such as the reflects the periodic, high-rate, meltwater lateral/distal and fine gravel (i.e., less than and greater valley-fill sands described flows within steep- walled than ice tunnels; the earlier, were deposited 2.0 mm) contents of the adjacent within meltwater few broad-crested eskerine bodies channelways. diamicton sediments (Shreve, 1985). probably reflect local, broad, ice-tunnel Broad-crested eskers Broad-crested deposition in channelways. eskerine sediment bodies are crevasses believed to The lithology of the natural-aggregate have formed mostly within tunnels bodies corresponds with the coarse and developed within the basal beds of the fine materials that had been entrained glacier ice just upgradient from the ice within the adjacent glacier ice. margin. The relatively broad form of the basal-ice tunnels is attributed to a series ACKNOWLEDGMENTS of freezing/thawing cycles of short dura- We thank the J. H. Shiely Company of tion that resulted in low rates of melt- St. Paul for allowing us to report and ex- water flow within the channelways pand upon findings developed during the (Shreve, 1985). Sediments of the in- course of a property evaluation. We grate- dividual broad-crested eskers and fully acknowledge the use of data dev- coalesced eskers (fig. 5) are fairly well eloped for Barton Sand and Gravel of Figure 6 Diagram of a tunnel-esker deposi- sorted and well bedded; they contain few Maple Grove and tional environment (modified from Rust and the Minnesota Depart- large cobble to boulder-size clasts. Romanelli, 1975). ment of Transportation (Mn/DOT). We also thank the Hennepin Conservation

44 District for the use of their aerial Jirsa, M.A., B.M. Olsen, and B.A. tion: Society of Economic Paleon- photographs. Bloomgren, 1986, Bedrock geological tologists and Mineralogists Special and topographic maps of the seven- Publication No. 23, p. 177-192. REFERENCES county Twin Cities metropolitan area, Shreve, R.L., 1985, Esker characteristics Bonestroo, Rosene, Anderlik, and As- Minnesota: Minnesota Geological in terms of glacier physics, Katahdin sociates, Inc., 1985, Gravel mining Survey Miscellaneous Map Series, M- esker system, Maine: Geological area plan: City of Maple Grove (MN) 55(l:125,000-scale). Society of America Bulletin v. 96, no. files, 357 p. LeB. Hooke, R„ B. Wold, and J. Hagen, 5, p. 639-646. Drewery, P., 1986, Glacial geologic 1985, Subglacial hydrology and sedi- U.S. Geological Survey, 1967, Osseo processes: Edward Arnold, London, ment transport at Bondhusbreen, quadrangle, Minnesota (topographic 276 p. southwest Norway: Geological So- map, 7.5-minute series, 1:24,000- Hoagberg, R.K., 1980, Geology and ciety of America Bulletin, v. 96, no. 3, scale). mineral resources of the Minneapolis p. 388-397. Wright, H.E., Jr., 1972, Quaternary his- (7.5-minute) quadrangle, Minnesota: Meyer, G.W., and M.A. Jirsa, 1984, Ag- tory of Minnesota, in Sims, R.K., and Minnesota Geological Survey files. gregate resources inventory, Twin G.B. Morey [eds.], Geology of Min- Hobbs, H.C., and J.E. Goebel, 1982, Cities metropolitan area, Minnesota: nesota: a centennial volume: Min- Geologic map of Minnesota, Quater- Minnesota Geological Survey Infor- nesota Geological Survey, p. 515-547. nary geology (scale, 1:500,000). mation Circular 20, 16 p. Hunt,C.B., 1972, Geology of soils: W.H. Rust,B.R., andR. Romanelli, 1975, in Freeman and Co., San Francisco, Jopling, A.V., and B.C. McDonald 344 p. [eds.], Glaciolacustrine sedimenta-

Evaluation of the Economic Usefulness of Earth Materials by X-Ray Diffraction

Randall E. Hughes and Robin L. Warren Illinois State Geological Survey Champaign, Illinois 61820

methods ABSTRACT appropriate for these types of investigations. X-ray diffraction (XRD) analysis makes use ofa monochromatic beam ofradia- tion, commonly CuKa to identify and quantify mineral composition. Recent ad- XRD APPLICATIONS vances in XRD instruments have made it possible to rapidly characterize large The Survey's clay mineral database numbers of samples at relatively low includes cost. New instruments have sufficiently high information on more than resolution for analyzing bulk materials, unlike earlier XRD units that required 100,000 samples analyzed by X-ray dif- separate analyses poorly offine, crystalline clay minerals and coarse nonclay fraction techniques. Most of the samples minerals such as quartz, orthoclase, plagioclase, calcite, and dolomite. However, were analyzed to study stratigraphic since fine clay minerals often control colloidal properties and may affect other relationships in Quaternary glacial material characteristics, a separate sample of thefine fraction (<2 0\imto<01 deposits, investigate depositional and \im) is usually analyzed. diagenetic patterns associated with Penn- A major shortcoming of earlier XRD sylvanian instruments was a lack of resolution of coal strata, and estimate the amorphous or poorly crystalline constituents. This shortcoming can largely be resource potential of argillaceous overcome by defining the broad diffraction (clayey) band ofthese components as a diffrac- materials of all geological ages. tion peak. This technique makes it possible to calculate an index of, for example Resource evaluation the intensity constituents of such as volcanic glass and coaly material, andform An accurate a ratio their intensity XRD analysis yields a of to the total adjusted intensity all mineral of peaks. rapid This report describes sample estimate of the suitability of a preparation, analytical methods, and quantifica- material for virtually tion methods used at the Illinois any use—from State Geological Survey (ISGS), and application landfill covers, terra cotta, of XRD analysis to the evaluation of several earth materials— refractory aggregate fired- ware, and clay raw materials, and pelletizing agents to building absorbent clays. XRD results can also be advantageously used to correlate foundations and earth fill. Although stratigraphic units, determine the orientation (fabric) ofplaty analyses or fibrous minerals, of clay mineral content of a evaluate the progress ofdiagenesis and weathering, deter- material mine the cause and usually correlate with particle- cure ofgeotechnicalproblems, monitor mineral processes and size analyses of the clay-size evaluate waste disposal sites. Chemical analyses and fraction, computer programs help to XRD refine the analysis and analysis directly reveals the min- increase the accuracy and precision of the evaluation eralogical composition—and indirectly an approximate chemical composition of the sample—regardless of the size of INTRODUCTION mineral grains. In XRD has a wide range of applications addition, mineralogical X-ray diffraction (XRD) is an analyti- analyses often clarify to the industrial minerals industry as well aspects of material cal method in which a monochromatic properties that as to the geological and material sciences. chemical analyses fail to beam of radiation is used to identify explain. For example, and It is particularly useful in geological differences in the quantify the mineral composition of distribution earth studies related to exploration, controlled of chemical constituents materials and other crystalline substan- among minerals mining, and processing of mineral resour- in different materials ces. When X-rays strike a sample and are result in different ces; investigations of weathering proces- firing properties for diffracted by the crystallites samples having in the ses and diagenetic, hydrothermal, and identical bulk chemical sample, the characteristic diffraction compositions. pat- metamorphic changes in geologic We have found that, in tern produced can be recorded and shown general, materials; and monitoring of mixing and XRD data on mineralogical graphically on a diffractogram. composition The process reactions of materials during (including data on the heights, areas, shapes, and positions of presence of amorphous their conversion or use. In this report we material such as the peaks on the diffractogram (fig. coaly or glassy 1) (1) describe how ISGS geologists and phases) are useful in provide information not only about the evaluating almost other earth scientists and engineers are any questions involv- mineral composition of the sample ing the discovery, as a using XRD to solve a wide range of development, and use whole but about each of the minerals of earth materials. geologic problems, and (2) summarize present in the sample. Figure sample preparation and quantitative 1 shows XRD patterns for a shale that could be used for common and

47 face brick and red-fired ware. In evaluating a clay material for these or other clay product applications, four questions are paramount:

• Does it contain enough kaolinite to give extended firing range and/or refractory properties?

• Does it contain enough expandable clay minerals to qualify as an absorbent and barrier material? • Are its quartz and feldspar contents optimum for a particular product or use planned on the basis of clay mineral

content? (For example, if the material is kaolin, is the quartz content low enough that it can be used for paper filler ap-

plications? If the material is illitic common clay, is the quartz content high enough to permit rapid and thorough firing?)

• Does it contain any deleterious minerals such as calcite, dolomite, pyrite or marcasite, siderite, jarosite, or gypsum?

Questions such as these can often be answered in less than 30 minutes of instrument operation and pattern analysis. Because the new, automated diffractometers can operate almost unattended on a 24-hour, 7-day schedule, the time required for sample preparation and interpretation of results has become the principal factor limiting productivity in many laboratories. Aggregate materials can be rapidly evaluated by XRD analysis (fig. 2). The amount of calcite, dolomite, and other phases can be determined with high precision. The magnesium content of calcite and the iron content of dolomite can also be measured by XRD. Contaminants in limestone and dolomite aggregates 3177G OK Roof Shale such as quartz and illite are easily -2u, ethylene glycol detected by XRD and can be studied in detail by dissolving the carbonate frac- K+C tion with acid before diffraction to con- centrate the insolubles. Compositional trends in an aggregate deposit can be

quickly estimated by XRD. Figure 2 illustrates the XRD pattern of two aggregates from Illinois—one calcite rich, the other containing mainly dolomite.

Figure 1 XRD traces of a typical roof shale (Energy Shale) of the Herrin (No. 6) Coal. Top (a) is a random bulk mount; middle (b) is a bulk smear mount; and bottom (c) illustrates the diffractogram of an oriented, -2 u.m slide. C,

chlorite; I, illite; K, kaolinite; CI, peak common to clay minerals; Q, quartz; Kf, K-feldspar; Pf, Degrees 2G, Cu Ka plagioclase; 1 and 2, denote peaks for 1M 1 1 1 1 -| 1 1 t- i i t- r r 4 14 (diagnenetic) and 2Mi (detrital) illite polytypes.

48 CPS Stratigraphic analysis 18500.0- XRD analysis of mineral composition has provided critical data for stratigraphic 16650.0 AGGREGATES FROM ILLINOIS interpretations at the ISGS for more than Upper = R17342, three decades. The recognition of in- 14800.0- dolomite (D) Lower = R17257, dividual units and delineation of their calcite (C) 12950.0- boundaries within Quaternary, Tertiary, and Cretaceous deposits have often simply 11100.0- been a matter of sorting the XRD patterns into types (e.g., patterns dominated 9250.0- by illite-chlorite, soil kaolinite, weathered expandable clay minerals, or any 7400.0- recurring association of minerals) (Frye, Willman, and Glass, 1964). Mineralogi- 5550. 0-| cal trends in Pennsylvanian underclays can be similarly described by type desig- 3700.0- nations (Parham, 1964; Hughes, De- 1850.0- Maris, etal., 1987). Most of the Survey's Quaternary studies have been based on D 0.0- the percentage of illite in unaltered Ts 34 diamictons (tills). However, Glass and Degrees 28, Cu Ka Killey (1986) have reviewed studies in 9 RD ° f d°,0mite a re ate u er and limes ^^ " 9 < PP > t°™ d°wer). quartz; D,D dolomite.cSomife Q, C, calcite; which distinctions have been made on the basis of calcite-dolomite ratios, ver- tive stability of minerals is also control- measures of platy particles miculite oriented per- content, lepidocrocite or led by the size of the mineral grains. pendicular to the sample surface; and hkl goethite presence, and the illite to Much remains to be studied about the peaks describe platy particles at some in- kaolinite + chlorite ratio. Ongoing ISGS mineral alteration in different particle- termediate angle with the surface. In nor- research on Quaternary materials in- size fractions of modern and ancient soils. mal shales 001 peaks dominate cludes slabs cut recalculating raw data from The possibility that a till may weather parallel to bedding and OkO peaks weathered are or altered materials to unal- in a unique way and that the environment most prominent in slabs taken perpen- tered equivalents (personal communica- during weathering may produce distinc- dicular to bedding. Webb and Odom's tion, H.D. Glass, ISGS) (see TCI, table 1, tive alteration patterns suggests that results suggested that increases in method I) and extending and testing the many profiles that were previously im- preferred orientation and salinity during hypothesis that all products of a major ice possible to interpret may eventually yield deposition were negatively correlated. event have similar mineral compositions useful information. Hughes, DeMaris, et Epoxy-penetrated, oriented slabs (Glass have and Killey, 1986). If this hypo- al. (1987) noted that the type of mineral been used at the Survey to study orienta- thesis were correct, it would be possible alteration in clays associated with coal tional changes induced by compaction to relate even isolated outcrops of till or measures may indicate the dominant and shear of earth materials. Preferred outwash, lacustrine or fluvial plant group(s) deposits, that caused the alteration. orientation of minerals and other than clays perhaps loess to a particular ice ad- As a result, studies of paleosols may can be studied by this technique, vance. as can provide new information about the en- minerals and compounds in manufac- XRD mineralogical analysis data vironment can and the floral population tured products. indicate the relative stability of minerals during poorly understood periods of during weathering Diagenesis research and soil formation. pedogenesis, nondeposition, and sub- For example, Hughes and Glass (1984) aerial exposure. Investigations of changes that occur in found that smectite in loessial paleosols sediments after deposition (diagenesis) Mineral orientation studies (ancient soils) weathers to mixed- and mass balances between sediment layered, Webb (1961) and Odom (1963) de- kaolinite/smectite (K/S) at a source areas and associated sedimentary monstrated that XRD techniques can be higher rate than would have been ex- deposits are among the most interesting used to determine the orientation of clay pected from the rate of feldspar-to- and potentially valuable geologic studies minerals within undisturbed slabs of kaolinite weathering. Hughes, DeMaris, rock being conducted currently. The discovery samples. al. Generally, samples mounted et (1987) similarly demonstrated that and recovery of oil and gas, metallic and parallel and perpendicular to bedding in certain underclays (paleosols under are nonmetallic mineral deposits, and coal analysed, and the ratio of 001 peaks to beds), chlorite—normally the least potable water all may be functions of the OkO, hOO, or hkl peaks is calculated stable mineral during weathering was to nature of associated sedimentary deposits — quantify preserved, the degree of orientation. In this while illite and orthoclase and the postdepositional changes that were method, 001 peak intensity measures the heavily altered by plant-induced have affected them. The petroleum in- + number removal of of platy particles that are oriented dustry K . Hughes et al. interpreted has been particularly active in re- parallel this to the sample surface or fissility, clay assemblage to indicate that the search on diagenesis; we suggest that paleosol for example; OkO and hOO peaks are was similar to a gley. The rela- other mineral industries could improve

49 CPS oxidation of the nonmagnetic troilite to a 5000 magnetic variety of pyrrhotite and mag-

31579 Oil Uel 1 Samples netite—which is then removed by mag- upper = ethylene glycol netic separation. The magnetic pyrrhotite lower • air dried content and the mineralogical changes resulting from changes of experimental conditions can all be accurately quan- tified and monitored by XRD. Similarly,

it is often possible to measure flotation selectivity with XRD. Continuous online monitoring of mineral processes by XRD and X-ray fluorescence from the same X- ray source is a promising new application.

Geotechnical problems Expandable clay minerals such as smectite can cause serious geotechnical problems, as noted in the keynote paper (Grim, this volume). The variety, amount, exchangeable cation, and moisture content of clays within a deposit have a major Figure 3 Diffractograms of <2 ^m slides from an oil well in the Cypress Sandstone. Upper trace is after ethylene glycol solvation, lower trace after drying in air. C, chlorite; Mx, mixed-layered il- effect on the properties of geologic lite/smectite; I, illite; K, kaolinite; Q, quart*, P/, plagioclase. materials. When the presence of hydrated (10 A) halloysite is suspected in a deposit, samples should be collected, processed, their exploration and recovery programs tant swelling clay will plug or damage the and analysed by XRD before and after by increasing research efforts in this area. formation. drying to confirm its occurrence. The two most important analytical Geographic and stratigraphic varia- Hydrated halloysite, which loses struc- techniques for studies of diagenesis are tions in mineral content of geologic tural water irreversibly, often gives con- X-ray diffraction and scanning electron materials can provide important clues fusing results in engineering tests when microscopy/energy dispersive X-ray that aid in the discovery, evaluation, and the samples are dried and rewet. Similar- analysis (SEM/EDX). XRD reveals the production of mineral resources. The ly, materials containing smectite, ver- mineralogical composition of a sample, location and orientation of ancient miculite, illite/smectite, or other expand- and SEM/EDX yields information on shorelines and similar paleogeographic able clays should be collected, mounted, petrographic relationships, grain size, features are often revealed by trends in and analysed by XRD at field moisture microfossils, and chemical zonation. mineral content The movement of fluids content whenever possible. Changes in- Clay mineral XRD analysis has been associated with petroleum migration and duced in hydrated clay minerals by min- widely used to estimate burial and ther- with certain types of mineralization ing, earth moving, compaction, and mal history (Hower, 1981) and resulting produces patterns of diagenetic min- wetting/drying can be detected and the petroleum accumulations (Burtner and eralization (principally clay minerals) magnitude of a variety of resulting Warner, 1986); differentiate authigenic that can be used to find these resources. geotechnical problems can be estimated versus "soil-type" kaolinite (Hughes et Other types of mineralization often can by the use of proper sampling techniques al., 1987a); and measure detrital versus be detected by halos of particular min- and XRD analysis. diagenetic illite content in Paleozoic erals associated with the deposits. strata (Hughes, Glass, et al., Aus- Waste disposal studies 1987; Mineral process monitoring tin, Glass, and Hughes, 1989). Further- Most hazardous waste landfill designs A wide range of mineral processes can more, XRD and SEM/EDX give practical involve argillaceous materials because be rapidly and efficiently monitored by information on the quantity of clay most earth materials that attenuate, ab- XRD. Figure 4 shows the XRD trace of a minerals such as chlorite, smectite, and sorb or adsorb, or otherwise immobilize coal char treated with carbon monoxide fibrous illite that react uniquely with wastes are in the clay mineral and related and ethanol to remove sulfur in a precom- fluids used in the completion, stimula- zeolite mineral groups. XRD can be used bustion cleaning process (Webster et al., tion, and enhanced recovery of oil and to study the attenuation process and the 1986). In this process, a number of chemi- solution mining wells. Figure 3 shows the reactions between wastes and clays. For cal and mineralogical changes occur. + XRD trace of the <2pjn fraction of a example, exchange of interlayer Na or Troilite (FeS), reduced by CO from ++ resevoir sandstone in which oil wells are Ca in smectite by metal ions in wastes pyrite/marcasite, catalyzes the removal often completed or stimulated with acid. often results in a change in basal spacing of organic sulfur. During organic sulfur Chlorite and perhaps illite in this sample of the smectite and the volume it occupies removal with ethanol, oldhamite (CaS) (identified on the diffractogram) will by 2 to 100 times. This change can cause + occasionally forms. The catalyst is rapidly react by hydroxyl layer and K shrinkage of clay barriers and leakage, or removed after the ethanol step by slight layer dissolution with acid, and the resul- expansion and destruction of the integrity

50 *

of other parts of the containment struc- CPS ture. The primary use of XRD in waste 1250.0 disposal problems is as a screening method; small 001 spacing changes that may result from the dilute solutions com- Sample: 1061x82 mon in the natural setting generally cannot be detected by XRD. Uses of XRD analysis: summary

Almost any geological problem requiring qualitative or quantitative mineralogic analysis can be advantageously attacked first by employing X- ray diffraction techniques. For example, XRD analysis can be helpful in

• locating, mining, processing, and manufacturing industrial minerals. • evaluating clay and shale resources, aggregate materials (sand and gravel, limestone, dolomite and lightweight materials), coals, industrial sands, gypsum deposits, and metallic and nonmetallic ores. RD ar '""" c°IE««™l desulluraalion i™ Zi ? *? ?' ""I process. Triolite or ovrrhotite • monitoring all types of mineral processing.

• correlating strata and estimating the de- and a 2-year-old Scintag diffractometer gree of weathering, diagenesis, or meta- instrument used determine how the pow- with a vertical 9/0 goniometer. This der morphism that has affected rock ma- should be ground and mounted in the newest unit has terials. a nitrogen-cooled ger- sample holder. manium detector and a 12-position • providing critical data on the degree of For routine analyses, powders should automatic sample changer. The Norelco orientation of platy or fibrous minerals be ground to about <100 Jim. If high has a for sealed proportional and a scintilla- levels geological and engineering compac- of accuracy and precision are re- tion tion detector, and both goniometers have quired, studies. the sample must be ground to 10 graphite • monochromators. The General evaluating the potential for contamina- Jim or finer. Careful grinding is essential: tion of Electric unit employs a geiger counter groundwater at existing or poten- overgrinding of some minerals can alter with a nickel Kb filter. All three tial waste disposal sites by determining units are their structure, cause a loss of XRD peak operated with radiation whether the earth materials would tend tubes that intensity and peak resolution, and to produce a Cu Ka beam, although sources attenuate or transmit wastes. The broaden the peak, resulting in a diffrac- of amount and Fe Ka radiation are available in the variety of clays and the togram that is difficult to interpret. Op- laboratory. presence of calcite or dolomite deter- timum grinding is especially important in mine the degree The types of X-ray diffraction instru- of seal and buffering analysis of heavy minerals because large capacity ments available to the researcher of waste repository materials. partly grains of heavy minerals have high X-ray • characterizing the mineral determine what types of samples can content of be absorption coefficients and are par- analyzed earth materials for geotechnical and how the samples should be ticularly evalua- opaque to X-radiation. If the tions of potential sites, evaluating prepared for analysis. The sample inner the and outer zones of a grain differ, hydration and colloidal state of preparation techniques discussed in the geotech- grinding or chemical removal of the outer next nically sensitive minerals such as clays, section are generic; most can be car- layer may be an essential part of the ried out and assessing the effects of possible dis- in any modern, well-equipped analysis. turbances of the site. XRD laboratory. Preferred orientation occurs when • solving a wide range of other geologi- anisotropically shaped crystallites are cal problems. SAMPLE PREPARATION oriented nonrandomly with respect to the A number of different methods can be surface plane of the sample. For example, XRD INSTRUMENTS used to prepare samples for XRD acicular grains and platy clay minerals At the Illinois analysis, State Geological Survey but by far the most common often have much we higher intensities for currently operate three diffraction method is to grind the sample into a fine some XRD peaks from the preferred units: a 36-year-old General powder, which produces Electric a characteristic orientation, and much model weakened inten- XRD5 with a horizontal gon- powder diffraction pattern on the diffrac- sities for all other peaks. The extreme ex- iometer (an togram instrument that measures the (fig. la) when X-rays are dif- ample of preferred orientation is the diffraction angles), a 20-year-old Norel- fracted by its crystals. The purpose of the nearly perfect orientation ofclay particles co unit with two vertical goniometers, analysis, the characteristics of the that results from sedimenting, vacuum material being analyzed, and the type of deposition, or smearing of clay particles

51 on slides (see the following discussion). water with a dispersing agent such as approach a random powder in degree of For identifying unkowns or quantifying sodium hexametaphosphate and some- orientation.

it achieve times modifier (pH 7 is about op- known phases, is desirable to a pH In approaching certain problems, such as possible. timum). The content of clay-sized as random an orientation as a detailed description of the particle minerals particles in the dispersion should be about Similarly, oriented slides of clay size of contaminant or valuable particles should be as oriented as possible. 3 percent solids by weight for best results. in an earth material, it may be helpful to designed (This requirement is approximate; at this Powder sample holders are analyze several narrow particle-size in- back-loading, and side- percentage, smectite gel and for front-loading, may tervals (such as <0.10 pjn; 0.10 to 0.20 the approximation kaolinite may be too thin for best results.) loading. Because best pjn) from a sample. To accomplish this, containing large of silt to perfecdy random particle orientation Samples amounts the sample should be resuspended and greatest quantitative and sand may require greater concentra- (and therefore the sized three or four times for each size in- the side tions in the dispersion than clay-rich precision) can be achieved with terval to remove most of the particles in design is generally preferred. samples would. The better the disag- loader, this that interval. A series of size separations the less required. Dis- However, when only a small sample of a gregation, sample based on a doubling of the diameter of the material is available, a shallow-well front solution of carbonates and organic particle is a common choice of size inter- material with acid and oxidizing agents loader is generally used, or an alcohol val. However, size interval fractions slurry is with the powdered sample increases the clay-size content of a made made on the V2 times Vnd (where nd is a and deposited on a glass slide. Any sample. Ultrasonic disaggregation or in- doubled diameter series (i.e., 1, 2, 4, 8) will tense mixing or grinding in a blender also method of grinding and mounting yield more detailed information. Each in- fairly orientation when increases the amount of clay-size par- produce random terval can also be weighed to obtain a used with materials having equant grains ticles. cumulative particle-size analysis. all fine-size cut of the dispersed slurry (grains having the same diameter in A Wet mounts can be quite useful for settling the sample directions); however, grains with fibrous, can be made by ac- some problems. For example, gels of Stokes formula ex- platy, or other habits, or cleavages that cording to Law (a smectite or other expandable clay min- fine pressing the settling rates of spherical cause preferred orientation require erals can be mixed with liquid hazardous to particles in a fluid) or by increasing the grinding and a side-loader mount wastes to determine the likelihood that a orientation achieve settling rate with centrifugal force. The reduce preferred and clay barrier will fail and crack; seal, ab- In- fine slurry, usually with water, can reproducible quantitative results. made sorb, and/or attenuate the wastes; or ex- glass or porous creased randomization of clay minerals then be sedimented on a pand and damage other parts of the slide, pulled onto Millipore filter or can also be obtained by spray drying a a containment structure. Furthermore, de- porous slide or smeared on a size-fractionated slurry of clay (Hughes by vacuum, tection of the hydrated (10 A) form of hal- Bohor, 1970). In new technique slide. In any case, the dried sample has a and a loysite is improved when the sample is laboratory, high degree of preferred orientation. being developed in our ISGS run wet. In this case, a sample must be quartz or few equant grains are present and coarse equant grains such as When maintained at field moisture, processed grains are strongly platy or fluorite are added to fine fractions of the clay wet, and analysed as a wet smear on a nearly perfect preferred orienta- fibrous or platy clays. The finer particles fibrous, slide or as a gel in a powder holder. tend to be randomized by the equant tion results. Quantification methods grains. Furthermore, partial randomiza- Three methods of preparing samples tion of clays can be achieved by sedi- with preferred orientation are currently XRD estimates of abundances of minerals in samples range from simple menting part of the silt fraction with the used in our laboratory. ratios of intensities clay fraction on a glass slide. The coarser descriptions and peak • A sample is dispersed in water, stirred, grains often randomize the clay minerals to complex calculations involving addi- and then settled to a selected size (usual- sufficiendy that additional details about tions of standard minerals, measurements ly <2^un); an aliquot of the sized frac- the clays can be observed. of sample absorbance, determinations of tion is then pipetted onto a glass slide, Thin-section mounts (without the chemical content, and computer pro- and the slide is allowed to dry (this is the grams employing chemical, diffraction, cover slip), polished sections, oriented oldest technique). rock slabs, variety of and other constraints to produce high- and a wide "as • For some applications, the sized aliquot precision determinations. The choice of received" samples can also be inves- prepared by the first method is placed method is usually determined by the re- tigated with XRD. The main requirement on a porous disk or slide and water is al- is that the quirements of the problem to be solved sample be properly aligned in lowed to drain through the slide or is ex- and the number of samples to be the X-ray beam. tracted by vacuum. analyzed. Rapid sample preparation and Early investigators, working with • A paste made of the whole material (fig. quantification techniques can be used for more primitive X-ray diffractometers lb) or a size fraction of the sample is most geological problems; however, the than those used today, were only able to smeared on a disk or slide. Whole- description of a new mineral variety, for study poorly crystallized clay minerals by sample smears yield reasonably high example, can take days or weeks. Most of preparing oriented aggregates (fig. lc). degrees of orientation if the material is the samples studied in the Oriented samples, still used for most rich in clay. If the sample contains abun- ISGS laboratory can be prepared and analyzed analyses of clays, are usually prepared by dant equant particles, little preferred sedimenting the sample on a glass slide. orientation results, and the sample may in a few minutes to a few hours. The clay-bearing sample is dispersed in

52 An approach we have found valuable in investigating certain problems is to define the appearance of the diffraction trace as a series of types (see stratigraphic analysis section). Underclays and similar materials were evaluated by this method by Parham (1964) and Odom and Par- ham (1968). Use of the type method avoids several numerical anomalies that occur in quantitative analyses. For example, two samples may contain equal amounts of a particular clay mineral, but the degree of crystallinity may indicate two different origins. Furthermore, as illite is weathered to illite/smectite (I/S) or detrital I/S is diagenetically altered toward illite, the bulk quantity of I/S is often constant; the distinguishing change is the variation in the I:S ratio. An early method of quanitification still used in our laboratory is to compare the intensity of mineral peaks in a sample to intensities for pure standards of the same mineral. This method assumes standard sample preparation and an equal coefficient of absorbance between previously analyzed (external) standards and analytical samples. A modification of this method applicable to clay minerals is to use external standards to calculate clay mineral content on a 100 percent basis, even though nonclay minerals are present in the samples. This procedure often reveals stratigraphic, weathering, or diagenetic trends that are missed when only absolute mineral content is calculated, because variations in nonclay mineral content obscure changes in clay mineral content. Table I describes the three methods of clay mineral analysis most commonly used in the ISGS laboratory. Method I, in use for more than 30 years, has undergone some changes during that time (Glass and Killey, 1986). This method uses peak height ratios among expandable (smectite or low-charge vermiculite), illite, and kaolinite + chlorite (fig. 5) from a diffractogram of an ethylene glycol-solvated, <2\im, oriented sample to calculate the clay mineral content on a 100 percent basis. The quantitative factors are based on pure clay mineral peak intensities; the factors for XRD instruments using a logarithmic intensity scale (GE) are different from those using linear intensity scale (Norelco). Other clay mineral ratios (table 1) such as vermiculite index (V.I.), diffraction index (D.I.), type composition index (T.C.I.), heterogeneous 002 after C, C4Ht. swelling 375 chlonte 004 after 375'C; K/, K-feldspar, orthoclase ?f, plagioclase

53 1

Table 1. Quantitative Methods of XRD Analysis

METHOD I. Clay Percentages, Nonclay Peak heights, and Clay Indices-Ethylene Glycol Solvation (E.G.) (used primarily for stratigraphic and soil profile studies).

Raw Data: (See figure 5 for peak identifications.) Peak heights of expandable-S1 EG, illite-I1 EG, kaolinite + chlorite (K + C)1 EG, counts for non-clay peaks, mm height of smectite, illite, and vermiculite (Vm-14A), color of XRD slide.

Calculations:

A. Adjusted clay intensity, Scl = S1 EG + 3 1 1 EG + 2(K + C) 1 EG for log scale, or

Scl = 1.4S1EG + 4I1EG + 1.8(K + C)1EGforlinearscale*

S1EGor1.4S1EG* 3l1EGor4I1EG* 2(K + C)1EGor 1.8(K + C)1EG* B. % E = % I = % K + C = Scl Scl Scl

Vermiculite Index (V.I.) = a. lfVm>I = + mm height of Vm-

b. lfVm< I = -mm height of I -Vm;

11 EG Diffraction Intensity Ratio (D.I.) = (K + Q1EG

Hetergeneous Swelling Index (H.S.I.) = mm height of expandable peak above low angle background minimum

%I1 + %(K + C) 1 Type Composition Index (T.C.I.) = = corrected %K + C %I2

%(K + C)2

1 From type composition, unweathered sample. 2 From unknown, weathered or altered sample.

NOTE: If TCI exceeds type composition, kaolinite is forming and/or illite is being weathered.

If TCI is less than type composition, chlorite is probably being lost by weathering.

Results: %E, %I,%K + C, VI. ,D. I. ,H.S. I., T.C.I, .presence or enrichment of kaolinite or chlorite, presence of mixed-layered kaolinite/ smectite, peak height of calcite and dolomite, and presence of lepidocrocite, goethite, and any other uncommon phases.

METHOD II. Clay Mineral Parts-ln-Ten (percentages) and Nonclay Heights—EG and 300°C (used for resource evaluations and general studies).

Raw Data: Peak heights of S1 EG, 11 EG, 11 Ht, (K + C)1Ht, I2Ht (002 illite heated), C3Ht (003 chlorite heated), K2Ht,C4Ht,Q, Kf, Pf.Cc, D(fig.5).

Calculations:

A. Adjust Peak Ratios, Iy = 1.0 S1EG Sy = 411 EG

I1Ht-(S1EG + I1EG) Ey I1EG

C3Ht Cy = I2EG

K2Ht Ky _ x Cy 2C4Ht

K1Ht NOTE: If chlorite is absent, Ky and Cy replaced by Ky = - 11 EG

Total clay intensity, Scl = Iy + Sy + Ey + Cy + Ky

Syx10(100) 100 10x10 < ) B. Parts-in-ten, PIT, S (%) = ;PITI(%)= ; Scl Scl

Ey x1 °( 10°) Ky x1 °( 10°) PITE(%)= ;PITK(%)= ; Scl Scl

pitc(%)= cy x1 °( 10°) Scl

RESULTS: PITor%-S,Vm (if all expandable = vermiculite ± smectite), E, I, K, and C; Peak heights for Q,K/, Pf.Cc.D, and other nonclays. * method,,,. SM^SSSSSSS!^^

H y ^Ml -^"t(y.z), ' nonclay peak heights trace (fig. 5). in counts from ethylene glycol solvated

Calculations:

(K A. + C)1Ht Adjust clay intensity, 2d = 11 Ht + 2.5

B- %I = H EG o /oE = I1Ht . I1EG Scl 2d

K + C)1Ht/2.5 ( %K = y . K + C)1Ht/2.5 x %£ = ( z

Corrected illite and smectite (E)

1) if only I/Sis present, %Ecorr = %E1 x smectite content of I/S; % Icorr = %H + (%E-%Ecorr) 2) if only smectite is present, % Ecorr = % E

if only vermiculite is present,

% "Ecorr" = %E1 (7-(l7-VmPkinA)) 7

"Icorr" % = % 1 1 + (% E - % "Ecorr")

P3^ P°SSIDIe t0 calculate dlscre,e smect.te (see part c, next) and then proportion according to (1 ) or (2) above. theotherphase

C. Alternate method for samples with discrete smectite.

1. adjust clay intensity

K+c 1Ht 2d = HHt + ( > 2.5

S1EG/6 2. % Smectite (S) = o = HHt - (11 EG + SI EG/6) ; /oE 2d 2d

I, K, % % % C, and corrected I and E are calculated as in B1 and B2 above.

D. Clay Index

1. Adjusted nonclay intensity

(Kf + Pf 2nc = .15G + Q + ) + 47Cc + .250 + .83PM 3

2cl 2. Clay Index (C.I.) = a ii„ia ' „ „ Cl-m^'- - 10 = all clay minerals icl 2nc + C.I. = 0.0 = no clay minerals

E. Collodial Index (CLI.) = C.I. x(% Ecorr); = CL.I. 100.0 = all smectite CL.I. = 0.0 = no smectite

heated scans, (K + C) = kao.Le 6thy,ene B^-o^aled and and cZ e peak at about 7A TkTc£?=*J^ ( ka° liniteT heated trace, I2Ht = second + chlori,e Peak at 71A on order illite oeTatsSIlEI J . S r3Ce Ht third order on heated trace, K2Ht = * ' " = chlorite peak at about 4.6A kaolin te peak a^abou l «A ^ = G = gypsum peak P * 355A n hea,ed ,race at 7.61 A ° ' Qv££ peak at 4 26A Kf T*,' ?, *f 3.2A, Cc ^33A P/ p,agioclase = calcite ' = peak at peak at 3.04A, D = doKe iaak = * at 2 MA pm PyM,en^ ""J marCaSite peak ' "* at 271A " EG = ethylene glycol solvated.

h6 ° 3 (M6th0d 375 C (M6th0d ° 3) 3?5 C Par, ' d6S " ' y S Pk H ^ ^ «* «* 325»C for K/S - TJlpeak heightZ°in counts above background. Pk A = peak area by integrated area or Pk H x width at 1/2 Pk H. index (H.S.I) and chlorite presence or smears. It can also be applied in a modi- of peak height intensities, but the most kaolinite peak changes are also deter- fied way to analyses of random bulk precise methods are based on peak areas. mined, as are the presence and intensities samples. The choice between calculating peak of nonclay mineral peaks such as calcite, Two additional steps are normally heights or peak areas usually is deter- dolomite, goethite, and lepidocrocite. taken in method III (table 1) to determine mined by the precision with which peak The color of the XRD slide is also the clay mineral content and equivalent areas can be measured, by the degree of described, because color often reveals smectite content of whole-sample smears variation in peak sharpness of phases in subtle indications of zonation and oxida- (or random-powder mounts). The first the sample, and the extra time required to

tion state. index calculation, the Clay Index, invol- calculate areas. Methods I and II are Method II (table 1) is similar to ves a ratio of the adjusted sum of the clay based on calculations of peak heights, and method I (peak height ratios are also cal- mineral peak area intensities to adjusted method III is based on measurements of culated), except that the ethylene glycol- intensities for the nonclay minerals. We peak areas. solvated sample is analyzed after being interpret this ratio to obtain information Software improvements on new or heated to 300'C for at least 1 hour. This on weathering, diagenesis, and colloidal upgraded computerized diffraction sys- method yields parts-in-ten results: smec- properties. Because colloidal properties tems have greatly increased the precision tite, expandables other than smectite of rocks are closely correlated with of XRD analysis. The current trend is to (vermiculite and I/S); illite; kaolinite; equivalent smectite content, a colloidal develop interactive, expert systems that and chlorite. The parts-in-ten results can index is calculated for many samples. enable the analyst to use several types of be easily converted to percentages by Detection, identification, and quan- analytical data to constrain the result and multiplying each by 10. If only one ex- tification of certain minerals require that use one or more methods of quantifica- pandable mineral is present, the expan- the samples be treated or modified in tion. The learning aspect (artificial intel- dable can be recorded as the actual some way during the analysis. For ex- ligence) of the new systems promises to mineral variety. This method is used with ample, all methods of clay mineral allow retrieval of results with special sedimented slides and <2|am smears. analysis in our laboratory use ethylene characteristics, quantity, association, or Method III (table 1) makes use of peak glycol solvation to expand I/S, ver- variety of a particular mineral, from very areas, which until recently were calcu- miculite, smectite, and similar minerals large databases. It may also be possible to lated as the width of the peak at half to reproducible spacings. Method I (table take advantage of stored "experience" to height times the peak height. (New instru- 1) requires only one XRD analysis of improve analyses of new sample sets. ments now make it possible to calculate a <2 |im sedimented slide that has been Another trend in quantitative XRD the integrated area of a peak by com- solvated with ethylene glycol. Methods II analysis is away from specially prepared puter.) This method requires sample and m require a second XRD analysis fine-sample fractions (such as <2 p.m) analysis after ethylene glycol solution after the sample has been heated to 300°C and toward whole-sample analysis by and after heating (fig. 5); it gives a per- to 375°C for at least 1 hour. Other treat- bulk powder or smear methods. This last centage of the four common clay min- ments that can help resolve complicated trend is the result of the higher resolution erals (E, I, K, and C) on a 100 percent diffractograms are analysis of air-dried available on newer instruments. basis (much like methods I and II). and ion-exchanged samples; expansion Factors affecting choice of However, for samples containing il- of kaolinite with an intercalation agent; XRD method and instrument lite/smectite, a further step is included: heating of gypsum to anhydrite; dissolu- It is a common misconception that the the smectite in I/S is portioned off as tion of carbonates, chlorite, and iron sul- newest instruments and quantitative "equivalent smectite," and similarly the fides with acid; removal of organic matter methods give the best results. In fact, the illitic fraction of I/S is added to the per- by low-temperature ashing, H2O2, or opposite is often true, at least in our cent of discrete illite. Vermiculite is not NaOCl treatment; and dissolution of laboratory. The choice of instrument and only recorded as vermiculite but also ap- glass, smectite, I/S, and dehydroxylated method is strongly dependent on the pur- portioned as though it were I/S with a kaolinite with caustic. pose of the analysis. For example, using smectite content of 4/7 (vermiculite ex- Samples that contain several minerals our 36-year-old GE diffractometer and pands to 14 A and smectite to 17 A in produce complex diffractogram patterns method I (table 1), we obtain precisions ethylene glycol; subtracting 10 A as the in which key peaks for different minerals of 2 percent, even though the resulting nonexpanding layer leaves 4 and 7 A, are superimposed; these samples may re- data are often much less accurate than respectively). These further calculations quire extra treatment to identify all the data obtained with newer instruments and are made because the degree of weather- minerals on the diffractogram. In general, methods. High precision results based on ing of nonexpanding clays, the degree of we prefer to obtain three or more isolated replicate analyses are particularly valu- diagenesis of expanding clays, and the peaks for a confident identification of an able for investigations of soil profile colloidal properties of a sample are all unknown phase. However, small a- development and stratigraphic affinities proportional to the amount of equivalent mounts of common minerals (such as between units. In such stu dies, the lack of smectite in that sample. New instruments quartz and calcite) expected in a particu- accuracy of method I ;an be an ad- and computer programs now make it pos- lar sample are often identified and quan- vantage. The kaolinite + < hlorite percent- sible to analyse complex mixtures of tified on the basis of only one or two age calculated from method I is com- smectite, vermiculite, and I/S. Method III peaks. monly greater than the amount actually is used on analyses of <2 pjn sedimented Some XRD methods of quantifying present generally by about 2.5 times. or smear slides and whole-sample mineral content are based on calculations —

56 But stratigraphic units and soil zones are time available, and the resources much that will Hughes, R.E., and H.D. easier to detect when the apparent be Glass, 1984, devoted to the problem all should differences are be Mixed-layer kaolinite-smectite magnified. considered when and selecting the analytical heterogeneous Studies of natural swelling smectite as in- resources or method to be used. dexes of soil material mass balances usually require weathering intensity, in the highest Abstracts from the possible accuracy, even at the 21st Annual Meet- ACKNOWLEDGMENTS ing expense of precision. of the Clay Minerals Society, For instance, the We are grateful to H.D. Glass, J.H. Baton Rouge, built-in error of 2.5 times mentioned LA. Goodwin, R.D. Harvey, D.M. Moore, and above, which could Hughes, R.E., P.J. DeMaris, be useful in a strati- WA. White for WA. White their helpful criticisms. and D.K. graphic study, would be Cowin, 1987, Origin of clay unacceptable in We also appreciate the support of our re- minerals in an analysis to determine resource recov- Pennsylvanian strata of the search by the State of Illinois. ery Illinois Basin: in or the processing and firing charac- Proceedings, Interna- tional Clay teristics of a shale deposit. An error could REFERENCES Conference, Denver, 1985, also occur Schultz, L.C., H. van Olphen, when using methods I and II to Austin, and FA.' G.S., H.D. Glass, and R.E Mumpton analyze a fine, smectite-rich material [eds.]: The Clay Minerals Hughes, 1989, Resolution of the such as loess Society, Bloomington, IN, mixed with a coarse illitic polytype p. 97-104 structure of some illitic clay material Hughes, R.E., H.D. Glass, such as till. Asample of this mix- minerals R.L. Warren, that appear to be 1 M: Clays and J.E. Crockett, ture would appear to have more loess 1987, The distribu- than and Clay Minerals, v. 37, no. 128- 2, p. tion and significance till, because the fine, lower density smec- 134. of illite polytypes in the titic particles preferentially Paleozoic strata of Illinois, settle more Burtner, RL., and M.A. Warner, 1986, in Abstracts from slowly in the beaker and on the slide. the 24th Annual The Relationship between illite/smectite correct Meeting of the Clay Minerals material balance for this mixture diagenesis and Society, hydrocarbon genera- Socorro, can be obtained by preparing NM. a smear or tion in the Lower Cretaceous Mowry Odom, I.E., random powder of the 1963, Clay mineralogy and whole sample or and Skull Creek Shales of the northern clay mineral clay mineral fraction. orientation of shales and Rocky Mountain area: Clays and Clay claystones overlying Another factor affecting coal seams in Il- choice of in- Minerals, v. 34, no. 4, p. 390-402 linois: strument is the ease of acquiring Ph.D. Thesis, University of data. Frye, J.C., H.B. Willman, and H.D. Glass When the type Mlinois at Champaign-Urbana, method of analysis is (1 143 p. 964), Cretaceous deposits and the II- chosen, any instrument Odom, I.E., and W.E., Parham, is equally useful. linoian glacial 1968, boundary in western Il- Petrography The choice then is based of Pennsylvanian under- on whether treat- linois: Illinois State Geological clays in ments such as ethylene glycol Illinois and their application solvation Survey Circular 364, 28 p. to some mineral or heating are required. For instruments industries: Illinois Glass, H.D., and M.M. Killey, 1986, with Prin- State Geological automated sample holders, an en- Survey Circular 429, ciples and applications of clay mineral vironmental 36 p. chamber may be needed to composition in Quaternary strati- keep Parham, W.E., 1964, Lateral treated samples from drying out or graphic: Examples clay mineral from Illinois, variations otherwise changing before in certain Pennsylvanian they arrive in U.S.A., in van der Meer, JJ.M. [ed.], underclays, the X-ray beam to be analyzed. This m Proceedings, 12th Na- fac- Tills and glaciotectonics: Proceedings tor can favor tional Conference of the Clay Mineral older instruments—in of an INQUA symposium on Genesis Society of which samples are run individually America, Atlanta, GA, and Lithology of Glacial Deposits, before 1963, WF. Bradley changes occur—even when the [ed.]: Pergamon Amsterdam, Netherlands, p. 117-125. newer unit would Press, New York, p. 581-602. give increased ac- Grim, R.E., 1989, Industrial minerals re- Webb, D.K., curacy and precision. Jr., 1961, Vertical variations search, in Proceedings, 23rd Annual in the clay Choice of method or instrument mineralogy of sandstone, may Forum on the Geology of Industrial also be affected by shale, and underclay members of Pen- the need to compare Minerals 1987: Illinois State Geologi- nsylvanian new data with previous results. If cyclothems: Ph.D. thesis, critical- cal Survey, p. 1-4. ly important University of Dlinois publications or data in a cer- Hower, at Champaign- J., 1981, Shale diagenesis, in tain field Urbana, 107 have been based on a certain p. Longstaff, F.J. [ed.], Clays and the approach, Webster, J.R., R.H. Shiley, it is best to use the same instru- R.E. Hughes, resource geologist: Mineralogical As- ment, if still C.C. Hinckley, G. V. available. If type methods are sociation Smith, and T. Wil- of Canada, Toronto, p. 60- used, results towski, 1986, from a particular instrument 80. Development of the carbon may simply make type identification monoxide-ethanol desul- Hughes, R., and B. Bohor, 1970, Random easier or furization process, make more direct comparisons clay in Proceedings of powders prepared by spray- possible. To the Third Annual summarize, the information drying: American Pittsburgh Coal Con- Mineralogist, v. 55 ference, required to solve a certain No. 29, Pittsburgh, PA, problem, the p. 1780-1786. Sep- tember 1986.

The History, Geology, and Future of Industrial Clays in Illinois

Randall E. Hughes, W. Arthur White, and Robin L. Warren Illinois State Geological Survey Champaign, Illinois 61820

vanian ABSTRACT strata contain shales and claystones that are Economically ideal raw materials for red- useful clay products in Illinois are made from raw materials fired ware; kaolinitic underclays ranging from Quaternary to Paleozoic in age andfrom claystone to siltstone in (low-grade refractory clays) that can texture The materials can be used be for five types ofproducts: (1) blended common ware to lighten red-fired ware; and un- and refractoryfired-clay products, (2) absorbent clays, (3) impermeable barriers, derclays that contain sufficient expan- (4) flux clays for cement manufacture, and (5) miscellaneous uses. Fired-clay dable clay minerals to have potential products include bricks, as field drain tile, stoneware and pottery, structural and absorbent or barrier clays. Pre-Pennsyl- decorative wall tile, sanitary tile, lightweight aggregate, and refractories. vanian Absor- clays and shales generally are bent clays have traditionally not been used to absorb oil (in floor-sweep compounds preferred materials for most uses because for instance) and as pet litter absorbent. New uses for absorbent clays include they contain carbonates and have binders andpelletizing agents too lit- for everythingfrom iron ore to coal • tle to animalfeeds kaolinite. However, these older slurry stabilizers and strata suspension aids for agrichemicals and similar materials- are usable in regions lacking higher absorbentsfor hazardous wastes; and impermeable barriersfor hazardous quality waste raw materials. The kaolinitic clay impoundments and similar structures. Flux clays are used in cement that is manufacture a minor component in the St. Peter to ont U!lti»8 P°int Energy use), trace element and J Z°[» sulfur contents, and Sandstone in La Salle County could be strength Miscellaneous potential uses include filling, stabilizing, pelletizing and used in many markets suspending currently using various agrichemicals; producing synthetic zeolites; providing sour- Georgia kaolin and Kentucky/Tennessee ces of alumina and other elements. Light-weight aggregate has been produced in ballclay. Illinois in the past, and excellent raw materialsfor this use are still In available this report we discuss the distribu- Thefired-clay industry has declined steadily in Illinois since the turn the cen- tion of of clay reserves, their geologic set- tury This decline can be attributed to a number offactors, including ting, replacement and their current or future potential ofstructural brick and tile with steel and concrete, substitution ofbrick veneer by for development. cheaper We also review the products, increasing use ofplastic drain pipe to replace clay field tile industry's past, discuss competition co-mining as an from southern states due to low labor and freight costs, a failure to alternative source of materials, and em- modernize plants, increased energy costs or shortages, tighter environmental phasize strategies that may increase the KSUfionsurbanencroachment.andthepoorbusinesspracticescommonamong vitality of the clay products industry in Il- small, family-owned businesses. New trends that tend to sustain the industry are linois. nearness to markets, preferential treatment for in-state producers, automation INTRODUCTION

The clay products industry in Illinois C tinue be a 5tmn and growing segment £? nr !° * of the industrial began with Indian pottery dating from mineral^t^Tindustry m Illinois. Increased local demand has resulted in about a search for 1000 B.C. Following European set- new resources, and this search identified several depositsforfurther testing and tlement, early pottery, evaluation. Some new brick, and tile interest has also developedforfired-clay products works expanded rapidly in the 19th Cen- tury. The industry benefited from pioneer research at the Illinois State Geological GEOLOGY OF CLAY RESOURCES Paleocene Porters Creek Formation oc- Survey (ISGS) Clay products are directed by J.E. Lamar currently made from curs in Alexander and Pulaski Counties, and R.E. Grim, early Quaternary, Paleocene, and Pennsyl- leaders in the the southernmost counties in the vanian state. developing field of industrial strata. Fired-clay products are The minerals. A Porters Creek is a smectite-rich clay key element produced from Pennsylvanian in the success of the clay in- shales and that is mined for absorbent clay products. dustry has been the Quaternary till and large investment in lacustrine deposits. The Cretaceous McNairy Formation, basic and applied research Quaternary deposits with potential value at agencies which occurs in southern Illinois, consists include such as the ISGS. This research produced the tills associated with Wiscon- of an upper and lower fine, micaceous one sinan, of the most extensive databases on Illinoian, and pre-Dlinoian ice ad- sand with a middle lignitic to silty clay the vances, composition of clay-rich strata in the Sangamonian and Yarmouthian called the Levings Member (Willman et nation. paleosols and gleys, lacustrine deposits, al., 1975). The Levings Member may Knowledge of the geology and Wisconsinan loess deposits. The of clay-rich have use for fired-clay products. Pennsyl- raw materials expanded greatly in the

59 Thick loess deposits, greater than 50 in. on

Thin loess deposits on till Cretaceous Tertiary 22] and clays and shales

Alluvial and lake deposits Pennsylvanian clays and shales %# w Residual clay deposits under loess Pre-Pennsylvanian shales

Thin lake clay and silts on till W///^t

Figure 1 Surficial clay deposits of Illinois (after Jonas, 1957). Figure 2 Bedrock clay deposits of Illinois (after Jonas, 1957). past few decades, partly because of im- loess, lacustrine clay, and stream al- brick; wall, floor, quarry, roofing, and provements in automation of instruments luvium. The distribution of surface field tile; partition tile and block; sewer such as X-ray diffractometers. These ad- materials—till, loess, lacustrine deposits pipe and flue liners; earthenware; stone- vances made it possible to investigate and alluvium—is shown in figure 1; the ware; art objects; lightweight aggregate; clays from individual localities in greater distribution of shales and claystones and cement. Nonrefractory clays have the detail and survey large numbers of beneath the surface materials is shown in same uses as shales. Till is used to make samples in a relatively short time. figure 2. some of the same products that are made Ceramic products have been manufac- Shales have been used in the manufac- from shale; loess has been used for brick, tured from shale, clay, diamicton (till), ture of common, facing, paving, and patio field tile, and light-weight aggregate

60 manufacture, and has also been mixed about 500°C to 600°C (900°F to 1100°F) by 1870 the manufacture with shale for pottery and of ceramic similar for several hundred years before Euro- products was increasing rapidly. products. Alluvium is used for pottery by pean settlers arrived. The first European In 1866, the first field tiles were amateur potters; it can be used in the settlers in Illinois brought their pottery manufactured by A. Horrock at Col- manufacture of cement if the magnesium with them, and shortly thereafter, bricks chester, who converted content is not his fire brick plant too high. and pottery were being shipped into the into a tile plant He Except for light-weight had difficulty selling aggregate, state from Europe, Louisiana, and down the first tile because the farmers refractory clays have been used for didn't the the Ohio River from states to the east believe man could improve on "God's same products as shales, for refractory In 1806, Robert Harrison set up the handiwork." bricks But when farmers saw the and shapes, refractory filler, caulk- first commercial pottery along Cahokia increased ing crop yields in tiled fields, the compounds, cements, and in stove Creek, miles 4 north of Edwardsville in field tile and boiler industry expanded rapidly. liners. Refractory clays are Madison County, and began to produce Many brick plants added to other nonrefractory began to produce both raw earthenware. A second pottery was estab- brick and field tile for materials to extend local consumption. the range of melting lished in Union County about 1820, and In 1875, a man named temperature, modify color, Hoefer made and increase a third was founded in Madison County the first paving brick the strength of the at Bloomington, Il- product. in Upper Alton a short time later. linois. Although the Pleistocene Economic trends at least partly tills used The first bricks made in Illinois for raw materials were poor in quality, the beyond the control of local producers probably were produced at the end of the bricks lasted caused a slump for 20 years. By 1884, a in the Illinois fired-clay 18th or the beginning of the 19th century plant in Galesburg had begun making products industry, but the industry may in St. Clair and Madison Counties. A paving have bottomed brick of such high quality that the out; investment in new, brick church in Cahokia is said to date term "Galesburg brick" highly automated plants has became the begun. In from 1699, but the bricks may have been standard for paving contracts west of In- contrast, the absorbent clay industry in imported. The first brick house in Illinois diana. Other the companies also made paving southernmost Illinois counties has was built for Major Nicholas Jarrot in bricks from Pleistocene prospered in the last 20 tills at years. Cahokia in 1801. The bricks were most Bloomington, Urbana, and other The future of clay products in cities. Illinois likely made by the soft mud method, Around hinges on 1868, the Galesburg Press several economic trends. If dried in the sun or in open sheds, and fired Brick and Tile concerns with hazardous Company was the first to waste disposal in stone-type kilns with wood and later commercially produce brick result in increased use of naturally from shale imper- with coal. At first, bricks were made from (Pennsylvanian-age Purington meable and absorbtive materials, Shale). all the surface material at the place they were Before usable 1868, bricks had been made only absorbent or barrier clays will to be used. from Pleistocene realize enhanced surface materials, but economic potential. If As villages increased in population the shales also the transportation made high-quality paving anomalies discussed in and size, brick plants were erected, and brick and field tile. the next section are eliminated, the fired- bricks were hauled from the manufactur- D.V. Purington came to Chicago from clay products industry will benefit im- ing yards for building purposes. In 1835 Maine mediately. in 1869 and established a lumber Even without changes in the first horse-powered brick machine yard. After the outside factors, Chicago fire in 1871 he the need for fired-clay was invented, and by 1840 the machine recognized the potential products and the for rebuilding availability of energy was adapted to steam power. After the the city. As an associate and raw materials near of Straus, Hahne major markets brick machine was invented, organized and Company, brick manufacturers, will probably result in growth in he this area. brick yards began to spring up in every was responsible for In addition, several promising new that company's use of direc- little village, town, and hamlet. Some of the Chambers Brick Machine, the tions^—such as products for hazardous artifi- these early plants produced bricks only waste disposal— a cial drying of bricks, and the steam shovel could increase the few months of the year; others operated to mine clay. markets for clay He later became president materials. Finally, it is longer, but few plants stayed open during of Purington-Kimbell clear that the clay industry, Brick Company, like all basic winter. Many plants were run by just two which at the time industries, would was claimed to be the benefit from a return to or three people, whose pay ranged from largest brick manufacturer investment strategies of the past—more under one 50 cents to a dollar for a 10- to 16-hour management. in concert He was also president of with attitudes of foreign day. If two plants existed near a city, the producers Purington Paving Brick Company of —in which long-term strate- plant that produced the least paid the least Galesburg, gies are considered a major paving brick as important as short- per day for labor. Many of the plants that manufacturer. term profit-taking. His brother, Charles, intro- operated for the longest days paid the duced a method to use crude oil in firing least and produced the least. brick. HISTORICAL DEVELOPMENT Ceramics industries in Illinois re- The modem Fired-clay products* building-tile industry in mained small and localized until after the Illinois dates from about 1880, when H.B. Native Americans in Civil Illinois used War. Until the railroads began to ap- Williams and C.H. Bess established the materials outside their living quarters pear in the for 1850s, all industrial growth Standard Brick Company their pottery and plant about a fired it in wood fires to was hampered by poor transportation, but mile east of Ottawa. The Standard Brick plant, which operated until about 1960, This section on fired-clay products was adapted from an unpublished manuscript written by Robert L. Major around 1970 (on file at the ISGS)

61 made building tiles from Paleozoic shales was invented by Hydraulic Press Brick litter material from the Porters Creek and Pleistocene till. Company in Kansas City just after World Clay; this use is the principal market for In 1882, S.E. King, another local War I. This company opened a plant with absorbent clay in Illinois today. The clay capitalist, organized and built the Ottawa a rotary kiln in St. Clair County, Illinois, has also been used in the last decade as Fire Clay and Brick Company plant near a short time later. When their patent ex- animal feed binder to increase the the Standard plant Chicago Retort and pired after World War II, Alton Brick flowability of animal feed. It can also be Fire-brick Company acquired King's Company, Postam Brick Company of used as a carrier, stabilizer, and suspend- company about 1900. Springfield, and Western Brick Company ing agent for various agrichemicals. The Illinois Terra Cotta Lumber Com- of Danville all opened competing plants. pany, organized in 1885, made hollow Alton Brick used a traveling-grate kiln ECONOMIC TRENDS flat-arch rile for iron construction, floor- and a mixture of Quaternary raw ma- Figures 3, 4, and 5 show total producing tile for wooden joists, ceiling tile, par- terials, coal, and coke. Postam and tion, unit value, and total value for clay tition tile, wall furring and defining, Western both used rotary kilns, Pennsyl- products for the years for which reliable column, girder, and beam castings. In vanian-age raw materials, and some coal statistics are available. Some of the peaks 1892 the Chicago Terra Cotta Company and coke as additional bloating agents. and valleys clearly reflect major wars, commenced manufacturing terra cotta Material Service Company started pro- economic panics, and the Depression. die in roofing a plant 3 miles northwest duction from two or three large rotary The peak in value during World War I of Ottawa. kilns in La Salle County, using the entire (fig. 4) was largely the effect of shipping According to Risser and Major (1968), local section from Quaternary to below blockades that decreased imports of clay 697 plants in Illinois produced clay the Canton Shale (Pennsylvanian), ex- products and raw materials, and from ex- products valued at $8.4 million in 1894, cluding gravels. This large increase in tensive mining of Anna kaolin to replace and the value of clay products grew con- production and the availability of cheaper previously imported products. (Anna tinuously until 1957, when it reached raw materials led to the closure of com- kaolin, suddenly much in demand, was $60.7 million. At the beginning of their peting plants. Alton Brick closed in 1963, being sold at cents per pound rather than study of moisture expansion of brick in Hydraulic Press Brick ended production the cents per ton being paid for common 1959, Hoskins, White, and Parham in 1970, Postam went out of business in clays.) Figure 3 shows the decline in (1966) could choose test materials from 1971, Western stopped production in production that has occurred in the last 25 about 60 plants making ceramic materials 1973, and Material Service closed its years. It is important to note that the two in Illinois. In spite of the growth in value plant in 1978. River sand replaced companies that produce absorbent clays up to 1957, Illinois dropped from second Hydraulic Press Brick's product, while are not included in the figures. Although rank among the states just before 1900 to Alton, Postam, and Western all were dis- the picture would seem considerably fifth in 1905, and has been too low to be placed by Material Service's large output, brighter if these figures had been added, ranked since 1905. At present, only three and Material Service's product finally the overall loss to the state of Illinois is or four plants are producing fired-clay lost out to slag, a waste product. more clearly reflected by the values for products and only about six plants are Absorbent clay fired products because this industry is producing clay products of any kind. more uniformly distributed in the state. Porters Creek clay (Paleocene) was Many factors contributed to the de- Kaolin used by Standard Oil of Indiana and cline of this fired-clay industry, but the Kaolin was produced near Anna from Sinclair Oil companies because of its main causes were (1) the change from early in this century until a few years after natural absorbent qualities for removing solid, load-bearing brick walls to steel the end of World War I. The kaolin was contaminants and clarifying, "bleach- and concrete construction with brick mined from sinkholes in Mississippian ing," and decolorizing motor oils. Its ab- veneer, (2) replacement of brick veneers and Devonian strata. One of the authors sorbent properties also made it useful for by less expensive wood, concrete block, was told that some of the kaolin that was sweeping compounds used to remove vinyl, and aluminum; (3) substitution of mined underground was plastic enough grease and water from garage floors in clay field tile by plastic pipe; (4) inexpen- that it could be rolled and loaded on mules service stations. At some time around sive northward (back haul) rail and truck and hauled out of the mine. Production of World War II, acid-treated bentonites transportation for products from southern refractory clay (rich in kaolinite) from the from Mississippi were shown to have a states; (5) poor management by small, Cheltenham Clay and underclay below higher bleaching capacity than the family-owned businesses; (6) pollution- the Colchester (No. 2) Coal has continued Porters Creek Clay. When oil companies control regulations; (7) labor costs and from before World War II to the present acid-treated the Porters Creek Clay, they strikes; and (8) low-quality raw The Cheltenham Clay and underclay added too much acid and obtained tittle materials. were mined together at most localities. or no decolorizing improvement. As a Rail haulage economics played a par- Until about 1980 this clay was added to result, the two oil companies changed to ticularly important role. Production costs refractory products; at present it is used Mississippi clay. for clay products are normally lower in only in ironstone pottery and high- Although Porters Creek clay had been southern states, and this price advantage strength bricks. sold occasionally as a litter material for is amplified when heavy southward flow Light-weight aggregate livestock barns, its main use was still for of freight traffic creates subsidies for oil decolorizing. About 1960, Ed Lowe The method for expanding clay and northward haulage in cars that would opened a plant in Olmstead to produce pet shale to produce light-weight aggregate otherwise return empty. Given the nearly

62 To,al lllinois cla production 2500 -i y 700 small, locally owned clay businesses in Illinois at the end of the last century (Risser and Major, 1968), it was to be expected that extensive consolidations would occur. However, several producers also went out of business because of family entanglements, especially the retire- ment or death of the founder, often the driving force of the business; a failure to invest in modern equipment; lack of concern about market shifts; and the recent investment strategy prevailing in the United States that emphasizes short-term returns. There are also some hopeful signs. Il- linois and surrounding states are among 1955 1960 the largest 1965 1970 1975 1980 1985 markets in the nation, and Il- linois is the Trends in Clay Products, 1955-86 nearest producer to several markets in nearby states. The state Figure 3 Illinois clay production from 1955 to 1986. has an excellent transportation system, several major investment centers, and a progressive and helpful attitude towards new business. Illinois and the federal government have several programs to promote Adjusted to 1982 dollars the industrial use of coal as a source of inexpensive energy. The state is known for its skilled labor force, but as a major industrial state, Illinois has higher-than- average labor costs. Therefore, new plants will have to be highly automated to be competitive.

GEOLOGY OF CLAY RESOURCES Raw materials for clay products are found in Holocene and Pleistocene, Ter- tiary, Cretaceous, Pennsylvanian, Missis- 1913 1920 1930 1940 1950 1960 1970 sippian, 1980 1990 Devonian, and Ordovician strata. Figure 4 Unit value of Illinois In clay production from 1917 to 1986. order of importance, the Tertiary (Paleocene), Pennsylvanian, and Quater- nary are the sources of all active opera- 250 Illinois Clay Products tions. Table 1 contains an outline of units that are or could be important as clay resources. The following review provides 200 a geologic framework to aid in the exploration for new clay resources and the evaluation of existing or previously mined deposits.

Holocene and Pleistocene

Holocene and Pleistocene deposits, the earliest sources of ceramic materials, continue to be used in small amounts. Be- cause most of Illinois is covered by these deposits, their potential for future uses is high. Quaternary history includes at least three major ice advances and at least three interglacial stages, including the 1917 1920 1930 1940 Holocene. From youngest to oldest, 1950 1960 1970 1980 1985 the order of Figure 5 Total value of Illinois clay events is: Holocene (intergla- production from 1 91 7 to 1 986. cial), Wisconsinan (ice advance), San-

63 gamonian (interglacial), Illinoian (ice ad- mosUy on Wisconsinan loess, are weakly stratigraphically by their clay mineral vance), Yarmouthian (interglacial), and developed in comparison with their San- composition (Glass and Killey, 1986). pre-Illinoian (formerly Kansan and gamonian and Yarmouthian predeces- The Wisconsinan deposits consist prin- Nebraskan ice advances). The Illinoian sors. Carbon 14 dating indicates that the cipally of diamictons in a series of reces- glacial advance penetrated farther south last ice at Chicago probably melted about sional moraines that become successively in this state than any other continental 14,000 years B.P. (Hansel et al., 1985); younger in the up-ice direction closer to glacier in the United States. The Quater- the youthful nature of the re-cent soils Lake Michigan (Willman and Frye, 1970) nary deposits of Illinois contain excellent supports this date. (fig. 6). The lower part of the Wiscon- stratigraphic records of glacial and inter- Wisconsinan ice moved into Illinois sinan usually consists of silt and alluvial glacial deposition, and interglacial soil from the Lake Michigan Basin and diamicton. development covered much of the northern half of the Wisconsinan-age loess deposits are The Holocene is represented mainly state. Fluvial and lacustrine deposits, thickest along the eastern bluffs of the by alluvium along and near rivers and varying from gravels to clays, occur both Mississippi and Illinois Rivers; they thin streams. Holocene peat, lacustrine depos- within the area of ice-associated deposits to the east-southeast. Older loesses exist, its, and sand dunes also formed on a small and beyond the ice margin. Wisconsinan but they have not been important for clay scale. The modern soils, devel-oped diamictons (tills) can often be traced products. The clay mineral composition

Table 1 Available materials by geologic age (after Willman et al., 1975).

CENOZOIC Bond Formation Quaternary "New Douglas" Shale Member Holocene Blue-gray, grading upward into yellow-gray, silty Alluvium, soil, loess, and lake sediments laminated shale Pleistocene "Grand Avenue of Springfield" Shale Member Wisconsinan Blue-gray below, brown near top; well laminated and silty Till, loess, alluvium, and lake sediments Modesto Formation Sangamonian "East St. Louis" Shale Member Loess and soil Blue below, poorly laminated, gray above, massive to well Illinoian bedded, sandy Till, alluvium, loess, and lake sediments Yarmouthian Farmington Shale Member Loess, soil Blue-gray to grayish brown, poorly laminated, many siderite Pre-Illinoian concretions in some areas, weathers brown; grades later- Loess ally from well laminated to massive

Till, alluvium, and lake sediments Carbondale Formation Underclay below Danville (No. 7) Coal Member Tertiary Clay is soft, light gray, slickensided (in Vermilion County, Eocene clay is red); much limonite present on most outcrops; lower Wilcox Formation part calcareous in La Salle County; in Grundy and Vermilion

Counties, it is more kaolinitic than other underclays of the Paleocene Carbondale Formation Porters Creek Formation Lawson Shale Member Buff clay with deep desiccation cracks; below oxidized Mottled green and gray, silty, massive shale upper surface buff zone, clay is dark blue to black and Energy Shale Member variable in composition Gray, clayey to sandy, some areas containing concretions Clayton Formation of calcareous concretions; plastic, poorly laminated Sandstone, silty clay Underclay of the Herrin (No. 6) Coal Member

Expandable-rich in most areas; illite and kaolinite increase MESOZOIC on east and northwest side of basin Cretaceous Canton Shale Member Baylis Formation (western Illinois) Blue-gray, weathers brown; well laminated Thin beds of silty montmorillonite and kaolinitic clay Underclay of the Springfield (No. 5) Coal Member in sandstone Expandable-rich in most areas Purington Shale Member Owl Creek Formation (southern Illinois) Blue-gray, clayey near base; grades upward into Sandy, silty, glauconitic clay sandstone; laminated in some areas McNairy Formation (southern Illinois) Francis Creek Shale Member Lenses of sandstone, lignitic clay (mostly kaolinite with Dark blue-gray in lower few feet, gray and sandier in minor illite and smectite), and siltstones upper part

Tuscaloosa Formation (southern Illinois) Spoon and Abbott Formations White clay cementing chert gravel and quartz sand; inter- Unnamed underclay of the Colchester (No. 2) Coal Member stitial clay is kaolinite Massive, gray to cream, slickensided, with occasional root traces; often kaolinitic and sometimes sandy PALEOZOIC "Greenbush" Shale Member Pennsylvanian Light gray, slightly bedded, sandy Mattoon Formation "Macedonia" Shale Member "Albion" Shale Member Gray, weathered, thinly bedded; concretions Blue-gray, well laminated, grading up into yellow-gray, sandy shale

64 of loess reflects its associated tills and Killey, 1986). Illinoian deposits cover Frye, 1970): high fluvial source area, which illite and dolomite con- vary in most of the state beyond the Wisconsinan tent characterize material montmorillonite (smectite):illite with an eastern content end moraine and often underlie Wiscon- source and high smectite Therefore, loess in western and calcite con- Illinois typi- sinan deposits as well. At most localities tent identify material with cally contains 60 to 90 percent mont- Holocene a western deposits and Wisconsinan source. morillonite, loess derived from the loess, silt, and/or alluvium overlie the Il- The Wabash River texture and mineral composition system contains abundant linoian (fig. 6). of glacial deposits illite, and that overrode bedrock loess east of the Illinois River In much of east-central, central, and or pre-existing Quaternary has an intermediate composition. San- deposits vary, west-central Illinois, a well-drained or depending on the characteristics of the gamonian interglacial time is represented gleyed Yarmouth paleosol that formed on underlying by either material. In general, there are a well-drained or a gleyed the uppermost pre-Illinoian till underlies three distinctive paleosol on the mineralogical charac- uppermost Illinoian tills. Illinoian deposits (Willman and Frye, teristics of One or more Quaternary deposits (Glass Illinoian tills are commonly 1970). One or more pre-Illinoian tills are and Killey, 1986; Willman, present, and they are distinguished from Glass, and commonly present below the Yarmouth Frye, one another 1963): (1) changes in the ratio of and from older tills by their paleosol. Pre-Illinoian deposits had either smectite (western source) illite and dolomite content to illite (north- (Glass and eastern or western sources (Willman and ern and northeastern source), and chan-

Cheltenham Clay Member Kinderhookian Series The Cheltenham Clay is the name given to a clay 3 to 30 Hannibal Shale ft thick that was deposited during the time cyclothems were Green to gray, argillaceous siltstone being deposited in the more rapidly subsiding parts of the Nutwood Shale Member Illinois Basin. This clay, which most likely supported vege- Dark brown to black, tation continuously slightly calcareous to noncalcar- during its accumulation, covered vari- eous; grades laterally and o. ous intervals during Spoon and Abbott vertically into gray Hannibal time. These mater- Shale 3 ials, which o contain from 50 to 100 percent kaolinite, are semirefractory to refractory o clays. They burn from buff to Devonian » white, depending on their iron content. The clay occurs Saverton Shale A only along the edge of the Illinois Basin, which was a -C stable Bluish to (/> greenish gray, silty, with thin, sandy and cal- area during Spoon and Abbott time. Equivalent >. units in careous strata the central part of the C basin are less kaolinitic, but may (D have economic Grassy Creek value. The origin, properties, and compos- Shale < ition of the Cheltenham Clay are essentially the Black shale, hard same as S those of kaolintic underclays in other localities and parts Sweetland Creek Shale 0) of the section Gray and green shale; contains some dark gray and black strata Mississippian Chesterian Series Blocher Shale

Grove Church Shale Lower 8 to 10 ft black, upper 6 ft gray Gray, fossiliferous, interbedded shale and limestone Lingle Formation Kincaid Limestone Misenheimer Shale Member Cave Hill Shale Member Dark gray to gray-brown, calcareous Upper 15 ft consists of calcareous dark gray and greenish gray Ordovician shale at the top and red and green shale below. The middle is limestone Neda Formation with interlayered dark gray to black shale. The Red shale interbedded with basal shale, about 75 ft thick, consists of dark red-brown or black oolite gray shale (locally containing spheroids of black) and includes some silty shale goethite or hematite; in a few places, contains and a little gray to dark gray and green siltstone layers of gray or green shale Q. Fraileys Shale Brainard Shale 3 Shale Greenish gray to green 2 containing beds of limestone, siltstone, and shale, dolomitic, silty o sandstone; dominantly a dark gray shale with a bed of red Scales Shale a shale below the top Orchard Creek Shale Member (in extreme southeastern £ (A Ridenhower Formation Illinois only) <0 Includes limestone Blue-gray upper part interbedded with and sandstone strata, greenish gray, limestone a! Claremont Shale Member but red, green, and brown shales are common o Dominantly gray 3 shale interbedded with limestone O- Valmeyeran Series Elgin Shale Member m Dominantly S Warsaw Shale dark gray shale; in places, all shale, but Blue-gray shale, usually interbedded with limestone, fossilferous, containing strata of argil- dolomite, silt- laceous limestone, stone, and sandstone quartz geodes, and beds of coarse silt and fine sand

Springville Shale Greenish gray to dark brownish gray, clayey shale; in places, mottled red and green and called "calico shale" State Pond Shale Member In a bed of soft glauconitic shale at base of the Springville Formation; greenish gray; contains phosphate nodules

65 ges in the ratio of calcite (western source) to dolomite (northern and northeastern source); (2) significant kaolinite content in deposits of glaciers passing over Penn- sylvanian bedrock, especially basal or bedrock tills; and (3) the formation of weathering products such as low- and high-charge vermiculite, well-crystallized and "smeared" smectite, and mixed- layered kaolinite/smectite, and the

associated alteration of chlorite and illite (Frye, Willman and Glass, 1960; Willman, Glass, and Frye, 1966). Sangamon and Yarmouth paleosols are extensively developed in Illinois. The paleosols are sometimes more than 3 meters thick; those in low areas of the paleosurface are usually covered by an accretion gley. The expandable clay minerals present in paleosols, pre-Il-

linoian tills, gleys, and backwater fluvial and lacustrine deposits are an untapped source of absorbent and/or barrier clays. 20 40 1- I "-i Pre-Illinoian and gleyed Illinoian diamictons contain larger amounts of expandable clays than do similar Wiscon- sinan units. However, the pre-Illinoian and Illinoian units contain larger amounts Holocene and Wisconsinan of kaolinite and are similar in quality to Cahokia Alluvium, Parkland Sand, and Henry Formation Wisconsinan deposits used as ceramic combined; alluvium, windblown sand, and sand and gravel outwash raw materials. Loess, tills, and lake deposits can be used as raw materials for

Windblown silt more than 6 meters (20 ft) thick fired-clay products. However, tills and re-

Equality Formation, silt. clay, sand in glacial, slackwater, and modern lakes Includes Lake Michigan Formation lated materials may cause problems be- (Holocene and Wisconsinan) cause they typically contain calcite and Moraine dolomite clasts, pebbles of all rock types,

Glacial till with some sand, gravel, and silt and pyrite/marcasite grains in unoxidized Ground moraine } materials. Coarse-grained material can be removed by screening. Calcareous ma-

Glasford Formation; glacial till with some sand, gravel, and silt; age ol some units is uncertain. terials cause crumbling or "pops" in the

product unless the product is treated with Pearl Formation and Hagerstown Member of the Glasford Formation combined; outwash sand, gravel, and silt water or steam during cool-down (gen- Kansan erally from 400"C downward). The bene-

Glacial till with gravel, sand, and silt ficial effects of water treatment of these

Pliocene - Pleistocene products during cool-down can be extra- ordinary. fired of Quaternary Mounds Gravel; brown chert pebbles, and sand A body material that often turns to dust in a few Teritary weeks without water treatment develops Clay, silts, and sands normal fired hardness, strength, and in- Cretaceous tegrity after water treatment. Water treat-

McNairy Formation (Baylis Formation in western IL); silty, fine quartz sand ment also reduces long-term moisture expansion of brick made from any raw materials (White, 1964). In some cases, Bedrock at or near the surface unweathered Quaternary materials contain enough pyrite/marcasite to cause Figure 6 Surficial geology of Illinois (after Lineback, 1979). SO2 air-pollution problems upon firing that require the extra expense of pollution abatement. Generally, Quaternary materials can be used advantageously to create unusual

66 —

aesthetic effects; for example, the perties of these clays may be partly at- western "Chicago common" Illinois (Grim, 1934), and hal- bricks (no longer tributable to the pore spaces within loysites of unknown age have produced) were available in been dis- a wide range diatoms and partly to interparticle pores. covered in southern Illinois (Lamar, of colors and color patterns. Although According to Moll and Goss (1987), only 1942). The Anna kaolin, found in part of the effect was the result of firing interparticle pores are effective in absor- sinkholes, seems to be heavily weathered in a scove kiln, the bricks also varied be- bance. residual clay. The halloysites, on the cause of the heterogeneity of the other feed As previously discussed, the Porters hand, are associated with mineralization material—a pebbly till from the south- Creek Formation currently is used main- in the fluorspar district and are assumed western suburbs of Chicago. Some ly for pet litter absorbent products, but oil to be of hydrothermal origin. Both Quaternary materials are blended with ma- absorbent or sweeping compounds, pel- terials were used in ceramics production, shales to add silt and sand and lighten letizing binder for animal feeds, binder and the kaolins were used for a few shales that would otherwise form heavy, for foundry sands, oil decolorizing specialty markets. difficult-to-fire bodies. Exploration during the Overall, however, materials, and bulking and suspending last two or three decades has failed Quaternary materials are usually to too low agents for agrichemical slurries also have yield any new Anna deposits. The chan- in quality to be a preferred source for raw been produced. Attempts have been made ces of finding halloysite are greater, and materials. to add sodium to the clay and use it as a at least one new deposit has recently been Tertiary replacement for western bentonites. For located. Significant some markets, the savings in shipping Tertiary deposits are pre- Cretaceous-age deposits also occur in in might offset the cost of additions of sent Illinois only in the southernmost Adams and Pike Counties in extreme sodium. counties of Alexander and Pulaski. A few western Illinois (Frye, Willman, and Tertiary gravel deposits have been found Mesozoic Glass, 1964). The Bayliss Formation con- north of this area, tains zones but the Paleocene The Cretaceous McNairy Formation in which the clays are thinner Porters Creek Formation, 50 to 150 feet and perhaps coarser crops out across southern Illinois to the grained than the Mc- thick in these two counties (Kolata, Nairy clays but have north and east of the Porters Creek out- abundant kaolinite, Treworgy, and Masters, 1981), is montmorillonite, and the crop area and west of the Cache River. Al- "soil kaolinite" that primary unit of interest for clay products. is assumed to be though the McNairy is predominantly a mixed-layered kao- The Porters Creek Formation and linite/smectite (Frye, as- sandstone, it contains abundant zones of Willman, and sociated Cretaceous and Tertiary Glass,1964). The deposits kaolinite-rich clay. The unit ranges from deposits could provide are the northernmost sediments ceramic or of the 25 to 450 feet thick (Kolata, Treworgy, absorbent raw materials that Mississippi EmbaymenL They dip south- would probably vary and Masters, 1981). Where present, the in value as a func- ward: the top of the Porters Creek Forma- tion of demand in Levings Member in the middle section of nearby markets. tion is about 350 feet above mean sea However, access to the the McNairy is a silty to lignitic gray to nearby Illinois, level where it is mined at Olmsted in Mississippi, and Ohio black clay; the upper and lower parts of Rivers could great- Pulaski County, but only about 200 feet ly extend the potential the McNairy consist of "fine, white to markets of clay below mean sea level at Cairo products (Kolata, gray, clayey, cross-bedded, micaceous, produced from the Porters Treworgy, and Masters, Creek, McNairy, 1981). fine-grained quartz sand" (Kolata, and Bayliss Formations. The Porters Creek contains sandy and Treworgy, and Masters, 198 1). Potter and Paleozoic silty zones and varies significantly in Pryor (1961) thought the sediments came The mineral Paleozoic in Illinois can be composition in the northern part from the southern Appalachians, and divided, for the purpose of of the Mississippi Embayment (Thomas this discussion Pryor (1960) suggested that the succes- of and clay products, into Pennsylvanian and Murray, 1989). Near Olmsted the unit sion represented the upper fades of a del- older strata contains (fig. 7). Pennsylvanian shales abundant montmorillonite, sig- taic succession. and underclays have furnished the nificant amounts of cristobalite, raw quartz, The clay mineral fraction of the Mc- material for most of the fired-clay muscovite/illite, kaolinite, and traces of Nairy is about 80 percent kaolinite with products made in recent years. The lower orthoclase, plagioclase, and chlorite. The significant amounts of illite, muscovite, Pennsylvanian units, sandier and cristobalite is poorly crystallized, more but the and smectite. Early settlers used these kaolinitic than the upper ones, are X-ray diffractogram of this mineral is kaolins for pottery, although no pottery presumed to represent fresh to clearly more similar to cristobalite brackish than to production exists at present. The ma- water deposits; shales, coals, and lime- opal CT or tridymite. Some cristobalite is terials could be separated during process- stones reflect the increasingly fine, present as diatom tests, which more are found ing and marketed as quartz, muscovite, marine characteristics of the mostly in the upper part of upper part of the section and and clay; however, the economic viability the section. Alternating layers of are concentrated in the 1 to 2 urn fraction. of clay production from this formation sandstones, underclays, coals, shales, and The montmorillonite content of the Por- with or without beneficiation—is ques- limestones frequently occur in cyclical ters Creek has been estimated to be 50 to tionable. Production for local ceramic or sequences called cyclothems (Wanless 70 percent, although some of the proper- cement plants has been evaluated at and Weller, ties of 1932), which represent the clay are similar to those of various times in the past and has shown repeated materials having cycles of marine invasion and a higher montmoril- economic promise. retreat. The vertical variation of Pennsyl- lonite content. It appears that the unex- Kaolins presumed to be Cretaceous in vanian strata has an important bearing pected absorbent and decoloration pro- on age have been mined near Anna in south- the uses of these clays because relatively

67 able barriers. The organic content of these underclays may also increase their absorbent capacity for immiscible organic wastes. Shales and claystones from strata older than the Pennsylvanian tend to have narrower firing ranges because of the absence of kaolinite, are often calcareous, and do not contain the range of clay minerals required for optimum plasticity and firing. For this reason, older shales have usually been exploited only where a local market is at some distance from Pennsylvanian sources. For example, older shales may be locally valuable for fired products in the Chicago area. Bohor and Ehriinger (1968); Kahn, Bhagwat, Baxter, and Berggren, 1986; B

:-:>j CRETACEOUS showed that the kaolinite in the pores of

~"| PENNSVLVANIAN sandstone of the St. Peter (Ordovician) in Bond and Matloon Formations includes narrow bells of Illinois isolated older formations along northern could be from La Salle Anticline tailings or mined from tailings ponds. ] PENNSYLVANIAN 1 * Formations Carbondale and Modesto There are also a few reports of kaolinite- PENNSYLVANIAN Caseyville, Adooh and Spoon Formations rich occurrences, often as sinkhole or MISSISSIPPI crackfill deposits, in Silurian or E2H Includes Devonian in Or- Hardin County dovician-aged strata (Frye, Willman, and DEVONIAN Includes Silurian m Douglas Champaign, and weslern Glass, 1964). These occurrences are Hock Island Counties small and erratically distributed and are SILURIAN Includes Ordovican and Devonian m Calhoun Greene and Jersey Counties not expected to yield economically m ORDOVICIAN minable deposits. CAMBRIAN Des Plames Disturbance—Ordovician to Pennsylvan an FUTURE DEVELOPMENT Faull The potential for improving or expanding existing clay businesses and Figure 7 Bedrock geology of Illinois (after Willman et al., 1967). creating new ones seems bright to us, primarily because of the potential market refractory, kaolinitic underclays are often suggested to Hughes et al. (1987) that il- area in and around Illinois. Many factors located near thick, upward-coarsening lite-rich sediment was the source material have contributed to increases and de- shales. Thus, products with a range of and that kaolinitic and illite/smectite-rich creases in various sectors of this busines. colors and degrees of refractoriness can clays were formed within the basin, The successes here and in other states be produced at a single location. The primarily as a result of the growth, decay, with similar advantages and constraints variations in clay content of shales make and diagenesis of plants. can be used as a guide for expanding or

it possible to control the feed clay so that Pennsylvanian raw materials for fired- creating new enterprises in sectors that

it is clayey enough for extrusion yet silty clay products tend to be kaolinitic (for have declined. Although it is virtually im-

and sandy enough for rapid and complete refractories) or illitic (for common ware). possible to isolate a single factor as the firing. The rapid compositional variations Fired-clay products are difficult to cause of business declines, investment in these strata reflect their complex produce from Pennsylvanian materials practices, management philosophy, labor origin. such as clays and shales containing costs, transportation, energy, innovation, The clays and shales of the Pennsyl- siderite, calcite, or dolomite concretions, product demand, new resources, and new vanian vary from flintclays (Hughes and pyrite or marcasite, or abundant expan- uses all contribute to the success or failure White, 1969), to fireclays such as those in dable clay minerals. Materials that have of clay businesses. The following short the Cheltenham Clay, to illite-rich units, (1) a range of mineral constituents discussion suggests ways to manipulate to underclays with a high mixed-layered providing varying degrees of refractori- these factors advantageously. illite-smectite content Different suites of ness through a wide firing range, (2) a In the fired-clay products industry, in- clay minerals or facies tend to be spatial- silty texture, and (3) adequate plasticity vestment in new, automated plants and a ly distributed in a regular way (Parham, are superior raw materials for fired ware. return to a long-term view of returns 1964; Odom and Parham, 1968; and Widespread underclays rich in ex- would greatly improve chances of suc- Hughes et al., 1987). Details of the dis- pandable mixed-layered illite/smectite cess. Rather than remaining at or return- tribution and content of the mineral suites should be usable as sorbents or imperme- ing to older sites of production, industries

68 should locate new mines and plants on the those in underexploited zones in the REFERENCES basis of the qualities of raw materials, Porters Creek; expandable-rich under- Bohor, transportation, markets, B.F., and H.P. Ehrlinger in, 1968, labor, taxes, clays; and clay zones from loesses, tills, Beneficiation of kaolinite energy availability, and cost. For ex- clay from paleosols, accretion gleys, and lacustrine ample, silica sand washings: Illinois a company may receive federal deposits. State Fired-clay research should Geological and state Survey Industrial Mineral aid and reduce costs by using evaluate ceramic raw materials on the coal rather Notes 36, 10 p. than natural gas or petroleum. basis of whole-sample mineral content, Frye, Abandoned J.C., H.B. Willman, and H.D. Glass, underground coal mines are and Odom and Parham's (1968) study of 1964, Cretaceous a potential source of deposits and the II- cheap gas. Further- the petrography of underclays should be linoian glacial more, new automated boundary in western Il- plants, which are extended to newer samples and materials linois: Illinois more energy efficient State Geological and more produc- other than underclays. In addition, whole- Survey Circular tive, also can reduce 364, 28 p. another major cost sample characterizations should often in- Frye, J.C., products that H.B. Willman, and H.D. Glass, fail to meet specifications. clude the engineering value of low-cost 1960, Gumbotil, Examples of potential new markets accretion-gley, and in- clay materials. Generally, we have found the weathering profile: Illinois clude field tile (Illinois is the north- State that collecting precise information about ernmost Geological Survey Circular 295, 39 and westernmost source of clay the composition, p. properties, and relative Glass, H.D., and M.M. field tile), and "Chicago Killey, 1986, Prin- common" brick, merits of materials for particular uses ciples and applications which is no longer manufactured. of clay mineral yields important long-term benefits, composition in Quaternary stratig- However, competition from plastic field many of which are not apparent during raphy: Examples pipe may make new ventures from Illinois, in field tile data collection and analysis. U.S.A., in van economically risky. der Meer, J.J.M. [ed.], Tills and glaciotectonics: Proceedings Patio, sidewalk, and landscaping brick SUMMARY of an INQUA symposium and tile are increasingly in demand. on Genesis Some Illinois has a rich clay-products his- and Lithology of Glacial Deposits, of the clay products imported to Illinois tory. Although most fired-clay products Amsterdam, fail under Netherlands, p. 117-125. local weather conditions, and a have declined in value in the recent past, Grim, R.E., return to 1934, Petrology of the kaolin patio brick and tile of the quality absorbent clays continue to grow in deposits of the near Anna, Illinois: Eco- previously mentioned Galesburg value. Clay materials are variably dis- nomic paving brick Geology, v. 29, no. 7, p. 659- would be a significant sell- tributed in Cenozoic, Mesozoic, and 670. ing point for an Illinois producer. In Paleozoic strata, and are widespread Hansel, A.K., D.M. Mickelson, markets such as field tile, roof A.F. tile, and geographically. Because of their special housing Schneider, and C.E. Larsen, 1985, brick, the clay industry can make properties and material concentrations, Late Wisconsinan a strong case for long-term and Holocene his- returns in spite the Porters Creek Formation, Pennsyl- tory of the Lake of higher initial costs. Michigan Basin, in vanian shales and underclays, and Although Quaternary evolution of the Great difficult to manage, co-min- Quaternary units provide all the materials Lakes, P.F. Karrow ing ventures such as extracting and P.E. Calkin underclay, currently used in Illinois clay production; [eds.]: Geological Association coal, shale, and perhaps limestone from they of vary respectively from most to least one mine Canada Special Paper 30, p. 39-53. can greatly increase profit- significant in terms of value of produc- Hoskins, ability. Reject J.S., W.A. White, and W.E. Par- materials such as the tion. Several avenues exist for new or im- ham, 1966, kaolin-rich tailings from Long-term dimensional silica sand proved clay businesses. The most changes in Illinois bricks and other production may represent an ideal and in- important factors in improving strategies expensive clay products: Illinois State Geologi- source of raw materials for one for improving profitability are optimizing cal Survey party and a Circular 405, 44 p. reduction of cost or even a site, raw material, and product selection; Hughes, R.E., small profit from waste and W.A. White, 1969, A disposal for the using raw materials in new ways; obtain- flint clay in other. Eventually Sangamon County, Il- it may be possible to ing more precise data on the composition linois, process certain shales in Proceedings of the Interna- for oil, trace me- of raw materials; investing in automated tional Clay tals, alumina, soluble Conference, Tokyo, 1969, silica, and products plants that efficiently use low-cost ener- v. L. such as glass building 1, Heller [ed.]: Israel University panels, fiberglass gy sources; and taking advantage of Press, Jerusalem, 291-303. insulation, synthetic zeolites, and p. glass or "waste" materials that have unexpected synthetic Hughes, R.E., P.J. DeMaris, W.A. White, minerals for isolation of uses. and D.K. Cowin, 1987, Origin radionuclides. Coal processing wastes of clay minerals in Pennsylvanian may also provide a source of raw mate- strata of the ACKNOWLEDGMENTS Illinois rials for clay products. Basin, in Proceedings of the We are indebted to E. Atherton, J.W. The study International Clay Conference, Den- of the relative value of Baxter, S.B. Bhagwat, J.H. Goodwin, and ver, materials for existing 1985, Schultz, L.G., H. van 01- and new markets is D.M. Moore for their reviews. We also phen, and a research area we believe would FA. Mumpton [eds.]: The produce thank I.E. Samson for her help in obtain- large Clay Minerals Society, returns from relatively small investing Bloomington, production data and company his- ments. IN, p. 97-104. Evaluation of different geological tories. materials Jonas, E.C., 1957, Pottery clay resources such as sorbents or barriers to of Illinois: Illinois waste migration is an obvious need. State Geological Survey Circular 233, 8 Among the candidate absorbent clays are p.

69 Khan, L.A., S.B. Bhagwat, J.W. Baxter, Odom, I.E., and W.E. Parham, 1968, Wanless, H.R., and J.M. Weller, 1932, and D.J. Berggren, 1986, Recovery of Petrography of Pennsylvanian under- Correlation and extent of Pennsyl- fine-grained quartz sand and kaolin clays in Illinois and their application vanian cyclothems: Bulletin, Geologi-

from abandoned sand washing tailing to some mineral industries: Illinois cal Society of America, v. 43, p. ponds, in Proceedings of the 11th An- State Geological Survey Circular 429, 1003-1016. nual Powder and Bulk Solids Han- 36 p. White, W.A., 1964, Permanent expansion dling and Processing Conference/ Parham, W.E., 1964, Lateral clay mineral in bricks: Illinois State Geological

Exhibition, Rosemont, IL, p. 327-338. variations in certain Pennsylvanian Survey Industrial Mineral Notes 18, Khan.L.A., S.B. Bhagwat, and J.W. Bax- underclays, in Proceedings 12th Na- 8 p. ter, 1986, Economic feasibility of tional Conference of the Clay Mineral Willman, H.B., and J.C. Frye, 1970, recovering fines from waste streams Society of America, W. F. Bradley, Pleistocene stratigraphy of Illinois: Il- of mineral processing plants, in [ed], Atlanta, GA, 1963: Pergamon linois State Geological Survey Bul- Proceedings of the American Associa- Press, New York, p. 581-602. letin 94, 204 p. tion of Cost Engineers: Chicago, IL, Potter, P.E., and W.A. Pryor, 1961, Dis- Willman, H.B., H.D. Glass, and J.C. Frye,

p. M.3.2-M.3.8. persal centers of Paleozoic and later 1963, Mineralogy of glacial tills and Kolata, D.R., J.D. Treworgy, and J.M. elastics of the Upper Mississippi Val- their weathering profiles in Illinois,

Masters, 1981, Structural framework ley and adjacent areas: Bulletin, Part I. Glacial tills: Illinois State

of the Mississippi Embayment of Geological Society of America, v. 72, Geological Survey Circular 377, 55 p. southern Illinois: Illinois State Geo- no. 8, p. 1195-1249. Willman, H.B., H.D. Glass, and J.C. Frye, logical Survey Circular 516, 38 p. Pryor, W.A., 1960, Cretaceous sedimen- 1966, Mineralogy of glacial tills and Lamar, J.E., 1942, Halloysite clay in Il- tation in the Upper Mississippi Em- their weathering profiles in Illinois. linois: Illinois State Geological Sur- bayment: Bulletin, American Asso- Part II. Weathering profiles: Illinois vey Circular 83, 4 p. ciation of Petroleum Geologists, v. 44, State Geological Survey Circular 400, Lineback, J. A., 1979, Quaternary no. 9, p. 1473-1504. 76 p. deposits of Illinois (scale, 1:500,000): Risser, H.E., and R.L. Major, 1968, His- Willman, H.B., and others, 1967, Geo-

Illinois State Geological Survey map. tory of Illinois mineral industries: Il- logic map of Illinois: Illinois State Moll, W.F., and G.R. Goss, 1987, Absorb- linois State Geological Survey Educa- Geological Survey. ent minerals, in Abstracts, 24th An- tional Series 10, 30 p. Willman, H.B., E. Atherton, T.C. nual Meeting of the Clay Minerals Thomas, A.R., and H.H. Murray, 1989, Buschbach, C. Collinson, J.C. Frye, Society: New Mexico Bureau of Clay mineral segregation by floccula- M.E. Hopkins, J.A. Lineback, and J.A. Mines and Mineral Resources, Socor- tion in the Porters Creek Formation: Simon, 1975, Handbook of Illinois ro, NM. Clays and Clay Minerals, v. 37, p. 179- stratigraphy: Illinois State Geological 184. Survey Bulletin 95, 261 p.

70 Effects of Rock Types in Illinois Gravels on Freeze-Thaw Test Beams

John M. Masters Illinois State Geological Survey Champaign, Illinois 61820

(fig. ABSTRACT 1). In one case, expansion of a single piece of ironstone (an oxi-iron-hydroxide The percentage of chert gravel, concretion) caused a test beam especially low-specific-gravity (<2 35) chert to break ag8 (fig. 2) while the egate *amPles used Maols other two beams in the Trnn'X ! ** ** Department of Transportation UVU1) to make Portland cement set expanded only moderately. test beams correlated strongly with expansion Results of repeated of the beams due to freeze-thaw testing tests of aggregate from these (ASTM C666-77). Not exceeding 3 percent by weight in any sample, gravel sources were also low-specific-gravity chert showed a very variable, and it strong was statistical relationship to expansion. Although difficult to correlate test results with no sample contained more than I j percent field performance by weight ofironstone, ironstone also correlated data. Reduction in the strongly with expansion maximum tally dolomite probably caused size of the gravel aggregate did some expanson. Other minor rock types considered suspect were weathered not always eliminate these problems. carbonate, cherty carbonate, pyritic dolomite As a sandstone-siltstone, conglomerate, shale, and result of the freeze-thaw testing, possibly weathered rocks in IDOT general These statements apply only to rejected 20 previously accepted gravels approved by /DOTfor use in gravel sources Portland cement-based highways and to the (29% of the state's total); percentages of rock types found in the study samples. this action greatly reduced competition and Samples collectedfrom selected altered the statewide distribution gravel-producing areas were studied by two of gravel methods. In Phase I, "as received" gravel sources for concrete. For example, wasfreeze-thaw tested and rock types were in the central identified on surfaces of slabbed test Illinois (Springfield-Peoriaj beams. Descriptions ofpolished surfaces of the slabs suggested region, gravel pits had been that cracksformed in and propagatedfrom expand- the only ap- ing pebbles were the only visible proved local sources of concrete-quality cause ofthe measured beam expansion. In Phase aggregate. I, individual rock types were sorted, Most of these sources were grouped, incorporated into beams, and tested. Statistical analyses disqualified on the basis of freeze-thaw of these data helped provide the conclusions sum- testing, marized above; however, the data were and aggregates had to often difficult to interpret and less than be conclusive. The variability the transported from greater distances. of expansion data, due partly to the relatively As small haul number and inconsistent positions ofhighly distances increase, the delivered expansive pebbles in the cores of test beams, price of aggregates was a major problem in the statistical analysis increases substantial- of the effects ofaggregate* hthology on freeze-thaw expansion. ly. For example, at a distance of 50 miles from a quarry, the price of crushed stone can be three times the cost at the quarry INTRODUCTION (Subhash B. Bhagwat, personal com- Because existing quality-control tests munication, 1987). An Illinois Department of Transporta- The obvious effect is were not identifying many of these tion (IDOT) a significant increase in the cost of statewide survey of Illinois troublesome con- aggregates, IDOT began struction Portland cement concrete projects. highways freeze-thaw testing all gravel sources pre- In response to revealed that "D-cracking" (deterioration concern about the viously approved for use in portland ce- decreased availability cracking) was a major contributor of concrete-quality to ment concrete pavements, using premature ASTM aggregates and unexplained variations pavement failure, which re- C666-77 in Method B (ASTM, 1979). In the freeze-thaw quires replacement or test data, IDOT and the major repairs to this program, three concrete test-beams Illinois State highways in many parts of Geological Survey (ISGS) Illinois (3x4x 1 inches) are 5 prepared for each ag- began a cooperative (Traylor, 1982). The term D-cracking research project gregate sample. The test beams are sub- (Masters and Evans, generally refers to "fine, closely spaced 1987) to identify the jected to 350 rapid (3-hour) freeze-thaw cracks which rock types in gravel that occur parallel and adjacent cycles; cause freeze- they are frozen in air at to 100 per- thaw expansion and longitudinal and transverse joints, in- attempt to explain cent humidity and thawed in water. The the variability in termediate cracks, and the free edges of previous test results. sample does not meet IDOT criteria if the This paper is a pavement slabs" (Stark, 1976). A major condensed version of the average expansion of the three test beams final report for that cause of D-cracking is the use of project. The project certain is greater than 0.06 percent. coarse was suggested by George Dirkes, aggregates that are susceptible to Execu- Freeze-thaw expansion data for repli- fracturing tive Director of the Illinois Association by frost action (Klieger et al cate of test beams made from some gravel 1974). Aggregate Producers. sources showed considerable variation

71 -

SAMPLE SELECTION Most of the gravel deposits that yield coarse aggregate for use in concrete are

in the northern half of Illinois (fig. 3). To ensure that the study samples would be as representative as possible, the geology of the gravel deposits and the freeze-thaw test results from each source were reviewed.

200 300 400 Number of freeze-thaw cycles

Figure 1 Inconsistent expansion curves resulting from the freeze-thaw testing of three replicate beams from gravel sample number 11.

measuring pin s • Gravel pit location % ,6 Sample number i • Special sample from

l Mississippi River valley

i Figure 3 Gravel pits from which gravel-ag-

i gregate samples were obtained for this study. i

i i Gravel deposits that are current sour- i

l ces of concrete-quality coarse aggregates

i in Illinois i are all of glacial origin. These i pits, located within the Holocene and i -axial line i— Wisconsinan map unit (fig. 4), recover

i gravel from the Henry Formation (Will- i man and Frye, 1970). A few Wiscon-

i sinan-age sand and gravel deposits are underlain by older glacial gravel deposits

i measuring pin of sufficient quality to be mined along J -" with the Wisconsinan gravel. Gravel deposits in northern (especially north- I / s' ^ /{^ eastern) Illinois contain the greatest 3 in. amounts of durable and unweathered rock types, mostly dolomite and relatively small amounts of igneous and metamorphic rocks (Masters, 1983, table

Figure Beam 1 of this triplicate 1). Henry Formation gravels progressive- 2 set of freeze-thaw tested beams from sample 1 was broken by the expansion of a large ironstone pebble (i) near the axial line. The sketch shows the ortho- ly farther to the south tend to contain rhombic shape of a test beam, the measuring pins protruding from the centers of the top and bot- greater amounts of weathered pebbles tom ends, and the axial line connecting the pins. and potentially deleterious rock types

72 such as chert, ironstone, sandstone, siltstone, shale, and coal. Samples were chosen from outwash- plain deposits in northeastern Illinois (3 samples) and from valley-train deposits in five river valleys: the Rock (4 samples), Fox (2 samples), Illinois (3 samples), Kickapoo (1 sample), and Wabash (3 samples) (fig. 3). All samples were collected by IDOT staff from production stockpiles containing nominal 3/4-inch top-size gravel. Two specially prepared samples, 5a and 5b, both taken from the same source, contained no particles larger than 3/4 inch; they were included in the study to determine whether the physical properties of a gravel aggregate will differ significantly when the gravel is (1) crushed with a jaw crusher or (2) crushed with an impact crusher. An additional sample from the Mississippi River valley source was compared petrographically with the other 16 samples but was not freeze-thaw tested.

CLASSIFICATION OF ROCK TYPES The classification scheme used in both Phase I and Phase II of the study to iden- Holocene and Wisconsinan tify the constituents of the gravel samples Cahokia Alluvium, Parkland Sand, and Henry Formation was designed to combined; alluvium, (1) allow for the pos- windblown sand, and sand and gravel outwash sibility that certain rock types or physical Wisconsinan properties of gravel may be more likely Windblown silt more than 6 meters (20 ft) thick. than other rock types or properties to cause deleterious behavior of aggregate in portland cement concrete, and (2) Moraine measure the rock-type variability of these Glacial till with some sand, gravel, and silt gravel samples. Ground moraine } The rock-type names used were based lllinoian on accepted rock and mineral names, and Glasford Formation; glacial till with some sand, gravel, and silt; age ot some textural and compositional terms (Bates units is uncertain and Jackson, 1980; Pearl Formation and Hagerstown Pettijohn, 1957; Member of the Glasford Formation combined; outwash sand, gravel, and silt. Moorhouse, 1959; and Pirsson and Kansan Knopf, 1947). Many rock types were Glacial till with gravel, sand, and silt classified by specific rock names, such as Pliocene - Pleistocene dolomite and limestone, or rock names coupled with modifiers, such as lami- Mounds Gravel; brown chert pebbles, and sand nated dolomite. Other rock-type names Teritary were derived by combining certain types :".J Clay, silts, and sands of rocks having similar compositions or Cretaceous origins. Each rock type is described and McNairy Formation (Baylis Formation photographed in Masters and Evans in western IL); silty, fine quartz sand. (1987, appendix). A 10-power hand lens Paleozoic and a low-power binocular microscope Bedrock at or near the surface (fig. 5) were used to identify rock types. Significant textural and mineralogical variations Figure were observed in the dolomite, 4 Simplified geologic map of surficial unconsolidated materials Pleistocenerieisrocene (gidoialralacial age)aas) the most and older, in Illinois (after Uneback, abundant rock type; therefore, it 1979 and 1981 ). was classified into four dolomite sub- types: (1) dolomite, relatively pure and

73 nonfriable; (2) laminated dolomite, having any type of visible layering; (3) silty dolomite, similar to the first two sub-

types but permeable and containing silt, sand, or clay; and (4) pyritic dolomite, similar to any of the other three but containing observable pyrite (Masters and Evans, 1987). Rock-group names were used as rock types for metamorphic and igneous rocks, which were present in relatively small amounts in the samples. However, some metasedimentary pebbles found in relatively large amounts were given

specific rock-type names (i.e., quartzite and metagraywacke) on the basis of their textures and mineral contents. Such distinctions for abundant rock types can be critical in evaluating freeze-thaw expansion; other studies have shown that a specific rock such as metagraywacke causes significant expansion (Stark, 1976).

Figure Equipment TESTING OF PROCESSED 5 used to identify, sort, and count rock types: (a) binocular microscope; (b) light; (c) slab from a test beam; (d) point-counting box; GRAVEL SAMPLES: PHASE I (e) combination hand lens, and (f) hardness tester; and (g) acid bottle in holder. Experimental design three-beam freeze-thaw test: 3 pounds of inch to number In Phase I, IDOT personnel obtained 4 mesh-size material. The 1- to 3/4-inch material, 24 pounds of 3/4- samples from the selected sources and coarse aggregate, sand, and cement were to 1/2-inch material, 12 pounds of 1/2- to mixed sieved them into four size-ranges. Sixty and cast into test beams, and the 3/8-inch material, and 21 pounds of 3/8- beams were pounds of material was split for each freeze-thaw tested. The beams were then sawed into slabs,

Top end Bottom and selected slab surfaces (fig. 6) were c end ^> ground smooth to facilitate point-count- Slab A 1 in. ing. The pebbles exposed on the slab sur-

Measuring faces were identified and counted; the SlabB Measuring 1 in. pin pin cracked pebbles in each rock type were also counted, and cracks in SlabC 1 in. the matrix were sketched. As a first attempt to estab- lish which rock types caused expansion,

1% in. 12 in. 1% in. statistical analyses were made relating Figure point-count data to expansion values. 6 Diagram of the top surface of a freeze-thaw test beam, indicating measurements and lines for Results rock-saw cuts. Slabs A, B, and C were cut from the central part of the beam. Both cut of other IDOT quality-control surfaces of slabs A and (faces C 1 , 2, 3, and 4) were studied for rock-type contents and deteriora- tests on splits of the study samples also tion features. Measuring pins protrude from the top and bottom ends of the beams. were compared with Phase I expansion values.

Beam expansion, popouts, cracks Freeze-thaw deterioration features such as cracks and surface ruptures (popouts) were visible on the exterior surfaces of the test beams. A study of the types of rocks involved in popouts revealed that only six rock types were found in the cores of popouts: chert was the most abundant, followed by ironstone and weathered carbonate. Comparison of the total numbers of pebbles in popouts with the average expansion values for the

I Figure 7 Point-counting box containing a slab (3x1 2 inches) under the wire grid. Phase test beams suggested that popouts

74 PerCen,afle 3nd aVera9e ,reeZ6-thaW 8XpanSi °n PerCenta9e °f each r0ck found ^Vra^sXriph^';j *">* in the trip.icate test beams of

Sample number 1 2 3 4 5a 5b 6 7 8 9 10 11 12 13 14 15 Average percent

expansion 0.028t 0.016 0.030 0.081 0.059 0.041 0.062 0.062 0.030 0.067 0.063 0.089 0.082 0.067 0.066 0.063 Sedimentary rocks

Dolomite 65.9 63.3 65.5 45.4 54.1 43.8 45.8 55.9 63.0 29.3 25.5 41.9 33.9 21.2 22.2 Laminated 18.8 dolomite 1.1 2.7 3.3 2.5 2.7 2.6 1.7 3.1 0.7 3.0 0.6 0.9 2.0 1.1 1.7 0.3 Silty dolomite 1.1 1.0 1.2 1.5 1.3 0.2 1.0 1.9 2.0 5.2 3.0 2.2 2.3 0.9 2.4 0.3 Pyritic dolomite 1.7 0.6 0.3 0.1 1.6 0.2 Limestone 3.2 4.4 3.9 4.9 1.8 3.4 2.8 3.9 3.1 11.4 9.6 7.4 8.1 10.5 Cherty 11.8 7.5 carbonate 4.6 4.9 1.6 2.9 3.2 3.5 2.9 5.5 5.1 3.7 2.6 4.5 4.4 3.1 3.8 63 Chert 7.2 6.3 7.7 22.0 20.3 23.8 23.6 10.2 9.8 15.4 24.5 16.0 19.2 22.4 18.0 24.9 Weathered carbonate 5.0 3.8 3.7 3.6 3.2 4.0 3.4 7.4 4.7 14.1 2.7 4.8 5.7 5.4 2.8 5.4 Ironstone 0.3 0.2 0.4 0.3 0.1 0.6 1.0 0.8 0.4 Shale 0.2 0.2 0.5 0.3 0.5 1.4 Sandstone-si Itstone 1.1 1.7 1.6 3.7 2.0 3.4 2.7 1.7 1.3 4.6 2.4 5.5 3.7 4.2 4.7 9.0

Igneous rocks Mafic 2.1 2.7 2.7 1.2 1.2 3.2 1.8 1.7 2.1 0.9 2.0 2.4 1.5 2.9 10.1 3.1 Weathered mafic 0.6 0.2 0.3 0.2 0.3 0.6 0.3 0.3 0.2 0.3 0.7 0.5 1.4 1.0 Coarse felsic 0.3 0.3 0.2 2.4 0.4 4.5 0.2 0.2 0.9 0.4 0.6 Weathered coarse felsic 0.2 0.2 0.2 Fine felsic 0.3 0.2 0.7 0.3 0.5 0.4 0.1 0.2 2.3 1.4 1.5 Massive 0.5 quartz 0.5 0.6 1.0 1.0 0.2 2.1 0.9 0.3 2.5 3.9 1.2 1.3 2.5 1.7 3.6

Metamorphic rocks Gneissic 2.3 3.0 3.0 3.2 3.8 3.7 2.7 2.6 4.1 2.1 3.6 3.3 4.1 3.4 4.7 5.2 Weathered gneissic 0.5 0.2 0.3 0.2 0.8 0.2 0.2 0.5 0.5 Schistose 0.5 0.5 0.3 0.2 0.2 0.2 0.2 0.6 Weathered schistose 0.2

Metasedimentary 1.5 2.2 2.2 4.6 2.5 3.2 3.6 3.0 0.3 3.7 8.0 3.1 5.7 11.9 Weathered 6.6 7.0 metasedimentary 0.2 0.1 0.3 0.3 0.3 0.4 0.2 0.3 Metagraywacke 0.5 1.7 1.5 2.0 2.3 3.2 2.0 0.9 0.6 1.5 2.0 2.2 2.8 2.2 0.9 2.4 Tillite 0.2 0.2 0.3 0.1 0.3 0.3 0.2 3.3 1.9 Quartzite 1.2 0.2 0.7 0.2 0.3 0.5 0.1 1.1 1.5 0.3 1.5 1.6 3.1 1.5

'TWO rOCk h/nfi« rnnnlnrr .A ...«~

75 I

samples 2 and 10. The similarity of the PHASE 70- results from the two control samples Freeze-thaw data leads to the conclusion that chert and O Dolomite A Chert dolomite in the other samples would 60- 1 probably react in much the same way. A 5b 2. A £ 12 Control data TESTING OF SELECTED A 13 f A' • Dolomite ROCK-TYPE GROUPS: PHASE U 50- 5a A A 6 Chert Experimental design 10 A In Phase II, freeze-thaw testing was E conducted on individual rock types and 15 ^40H l A groups of rock types to check and refine 5b Phase I data. An additional split (60 lbs) O of gravel in the designated weights of 30 — each size-fraction was taken from each 5a bulk study sample. Each O pebble in these 11 splits was identified and sorted into the 28 6" ° O O o 20- 4 rock-type categories used in Phase I (for 15 o P | each of the 16 samples about 12,500 peb- OO 13 , 2 bles were identified and sorted).

/ cj>° ° 2 After the samples were separated by 10- size and rock types, the beams were A made. The amount of each rock type ob- 10 tained was augmented by enough stand- • 10 ard, nonexpansive crushed dolomite to I I 10 20 30 40 50 60 70 80 make a new set of three test beams. For Chert and dolomite (%) example, if a 60-pound sample split contained 10 pounds of chert pebbles, that 10 pounds of chert was mixed with 50 Figure 8 Comparison of the percentage of chert and dolomite pebbles in the test beams with the percentage of cracked chert and dolomite pebbles in the test beams (point-count data). Each pounds of the standard dolomite to obtain point is identified by its sample number. Dashed lines connect values for the percentage of crack- the 60 pounds of coarse aggregate in the ed chert and dolomite pebbles in control samples not freeze-thaw tested with equivalent values correct size-range for test beams. Any for freeze-thaw tested samples. resulting beam expansion thus could be attributed only to chert. The average percentage of chert found freeze-thaw testing, two samples (2 and For the first five samples studied in in samples from the same area was also 10) were cast into beams and prepared for Phase II, every rock type except those variable; the greatest variations were in point-counting without being freeze- present in trace amounts (<0.05%) was samples from the Illinois River valley thaw tested. The amount of cracked chert individually cast into a set of test beams. (16.0% to 24.5%, samples 10 and 11, in sample 2 rose from 11 percent without Freeze-thaw testing of these beams table 1). More samples must be studied to freeze-thaw testing to 55 percent with provided expansion data for dolomite and evaluate such relationships more fully. freeze-thaw testing, whereas the amount chert; however, the less abundant rock The major deterioration feature found of cracked dolomite increased from 14 to types generally did not cause detectable on the slab surfaces was the abundance of 21 percent under the same conditions. expansion, probably because there were cracked chert pebbles. The striking ten- The cracked chert content in sample 10 too few of them in the test beams. There- dency of chert pebbles to crack and increased from 6 to 46 percent, and the fore, the procedure was modified for the dolomite pebbles not to crack is il- cracked dolomite content increased from last 11 samples; the same 28 rock types lustrated by the clustering of points in 3 to 12 percent. Thus, freeze-thaw testing were separated, but for testing they were figure 8. As a test of how much of the ob- cracked 40 to 44 percent of the chert but recombined into five rock-type groups served cracking actually occurred during only 7 to 9 percent of the dolomite in (table 2). These groupings were chosen to Table 2 Classification of rock-type groups for the Phase II series of freeze-thaw tests. provide (a) independent testing for chert

Group 1 : chert (group 1) and dolomite (group 2), the

Group 2: dolomite only rock types abundant enough to be individually tested in all samples; (b) a min- Group 3: laminated dolomite, pyritic dolomite, limestone, cherty carbonate imum of 6 pounds combined weight of Group 4: coarse felsic, fine felsic, mafic, quartzite, rnetasedimentary, metagraywacke, tillite, gneissic, rock types in the remaining groups (10% schistose, quartz of the 60-lb sample); (c) a separate group Group 5: ironstone, silty dolomite, sandstone-siltstone, shale, conglomerate, weathered coarse felsic, of sedimentary rocks (group 3); (d) a weathered fine felsic, weathered mafic, weathered rnetasedimentary, weathered gneissic, weathered separate group of unweathered igneous schistose, weathered carbonate

76 1

Table Total 3 percentage (by weight) of each rock type identified in each of the 60-pound gravel samples studied in Phase II. Sample number

5a i 5b 7 8 10 11 12 13 14 15 16* Sedimentary rocks

Dolomite 597 61.1 56.3 41.5 52.1 47.1 49.1 57.6 62.2 32.0 21.3 34.7 28.6 Laminated 15.2 19.6 20.2 1.6 dolomite 3.5 2.8 2.5 2.8 2.1 1.2 1.4 1.8 3.0 1.3 1.8 1.6 1.8 1.9 Silty dolomite 2.5 1.3 TR 1.6 2.1 3.3 2.7 1.9 1.6 0.4 2.1 0.8 6.2 0.9 3.0 3.0 2.6 2.3 Pyritic dolomite 0.7 0.1 1.3 1.1 2.7 0.3 0.7 0.8 1.5 0.3 0.4 0.3 0.5 0.1 0.2 TR Limestone 51 3.9 4.4 3.6 3.1 2.3 3.2 2.7 4.3 7.7 6.1 8.1 9.7 Cherty 9.4 10.9 9.4 1.8 carbonate 4.5 4.6 7.4 7.2 4.8 4.7 5.3 10.1 6.2 6.1 3.9 8.2 7.2 Chert 9.4 8.6 6.7 2.3 52 5.9 7.5 20.3 17.2 19.6 18.3 9.7 6.5 15.0 21.1 14.4 Weathered 15.6 19.0 15.0 21.4 21.7 carbonate 5.1 2.9 3.2 4.4 3.2 2.1 7.0 4.0 4.6 8.5 6.6 4.9 5.7 2.0 Ironstone 2.3 2.1 0.5 0.5 0.6 0.3 0.1 TR TR TR 0.1 0.1 1.5 0.2 1.4 0.8 0.4 0.4 0.2 1.4 Shale 0.1 0.3 0.3 0.1 0.1 0.1 TR 0.1 TR 0.7 TR 0.5 0.4 0.6 1.3 0.1 TR Sandstone-siltstone 2.9 2.1 2.7 2.8 2.0 2.4 3.2 1.6 2.9 5.7 7.1 4.2 4.0 Conglomerate 5.9 5.2 8.2 1.3 TR 0.1 TR TR TR TR TR 0.5 0.2 0.1 0.3 0.3 0.3 0.1 TR

Igneous rocks Mafic 39 5.3 2.5 2.2 1.8 4.2 1.7 1.9 1.6 3.1 2.4 4.0 4.0 5.8 Weathered mafic 6.1 4.1 4.7 0.4 0.5 0.3 0.2 0.1 0.1 0.3 0.2 0.6 0.4 0.6 0.2 0.2 0.3 0.2 0.5 Coarse felsic 0.5 0.3 0.4 0.3 0.3 0.3 0.2 0.2 0.2 0.3 0.2 0.5 0.4 0.4 0.3 0.2 0.2 2.0 Weathered coarse felsic TR TR TR TR TR TR TR TR 0.1 TR TR TR 0.1 Fine felsic 0.1 0.4 0.4 0.3 0.5 0.5 0.8 0.6 0.4 0.3 0.2 5.2 1.0 2.1 0.1 0.1 0.3 Weathered fine 9.6 felsic TR TR TR TR 0.2 Massive quartz TR 0.1 TR 0.1 0.1 0.9 0.7 0.3 1.0 0.1 0.1 1.5 3.1 0.8 2.1 1.5 0.7 1.6 3.4

Metamorphic rocks Gneissic 2.1 3.5 2.8 4.3 3.7 4.8 3.1 2.5 3.2 3.2 7.7 5.0 5.5 8.8 8.6 7.1 19.6 Weathered gneissic 0.2 0.2 0.2 0.4 0.3 0.2 0.4 0.2 0.5 0.3 1.3 0.2 0.3 0.5 Schistose 0.5 0.7 2.1 1 0.4 0.2 0.3 0.2 0.2 0.5 0.1 0.5 0.4 0.7 0.3 0.1 0.5 0.2 1.1 0.3 Weathered schistose TR TR TR TR 0.1 TR TR TR TR TR TR TR Metasedimentary TR 0.1 0.2 1 .1 1.3 1.4 3.1 2.9 4.0 2.5 1.6 1.0 3.1 5.7 4.9 6.0 9.1 8.7 Weathered metasedimentary 8.3 17.6 TR TR TR TR TR TR TR TR TR 0.1 Metagraywacke TR 1.1 0.8 1.0 1.1 1.2 1.3 2.2 0.8 1.3 0.8 1.4 2.3 1.3 1.2 1.1 0.8 Tillite 1.3 4.5 TR TR 0.1 0.1 TR TR 0.2 0.1 0.1 0.1 1.9 Quartzite 2.1 2.1 TR TR 0.2 0.1 0.5 0.8 1.0 0.8 0.1 0.2 0.3 1.2 0.6 0.8 2.9 2.9 2.0 3.6 Sample obtained from product stockpile for rock type data only and not subjected to freeze-thaw or other quality tests and metamorphic rocks (group 4); and (e) lained differ in their rock-type contents River valley-train a group of potentially deposits, dolomite deleterious rock (table In table 3). 4, related rock types are content varied types present in only from 24.0 to 39.6 percent very small amounts, combined; the samples are identified by and ironstone including ironstone, from 0.2 to 1 .4 percent. The silty dolomite, stratigraphic names (Willman and Frye, dolomite content sandstone-siltstone, weathered was fairly distinctive in rocks, 1970) and arranged by outwash-deposit and incompletely each valley-train system, ranging from 63 consolidated rocks area. Dolomite was most abundant (63% to 69 percent in (group 5). the Fox, 47 to 57 percent to 67%) in the McHenry County outwash in the Rock, 24 Phase II rock-type data are to 40 percent in the Il- summar- plains and the closely related Fox River linois, 22 to 25 ized in table 3. Statistical percent in the Wabash, to analyses were valley-train, and chert was least abundant just 2 percent in made by comparing the the Mississippi River val- weight percent of (5% to in 10%) these deposits (table 4). ley each of the sample. The igneous and metamor- five groups of rock types to All other samples were from valley-train phic rock the corresponding expansion contents (including weathered data and deposits containing abundant chert (15% varieties) in the samples from then comparing the weight percent of the valley to 22%); the deposits containing higher each trains ranged from 9 percent in rock type within a group to the ex- the Fox, amounts of chert tended to occur farther pansion 12 to 18 percent in the Rock, 19 to 30 per- data for its respective group. downstream at greater distances from the cent in the Illinois, 30 to 33 percent in the Rock-type variations glacial-age ice fronts (figs. 3 and 4). Wabash, and 69 percent in the Mississip- Within each The major gravel deposits in gravel production area the pi River Illinois valley sample (table 4). weight percent of from which the study samples were ob- several rock types varied widely; for instance, in the Illinois

77 Table 4 Summary of weight percent data for rock types identified in the study samples (table 3) and geologic names of deposits (fig. 4) and geographic sites from which samples were obtained (fig. 3).

Rock types (wt %)

Sedimentary Igneous and Weathered DIVISIONS OF GEOLOGIC TIME metamorphic igneous and Divisions of rock Total Weathered Sand- Other metamorphic stratigraphy Sample dolo- Lime- carbonate stone- sedimentary Iron- Geographic locations number mite stone rocks Chert siltstone rocks stone

QUATERNARY SYSTEM PLEISTOCENE SERIES WISCONSIN AN STAGE

Henry Formation (outwash deposits)

Batavia Member

(outwash plains)

McHenry County 1 661 5.1 5.1 52 2.9 4.6 0.5 9.7 0.6

2 67.1 3.9 2.9 5.9 2.1 5.0 06 126 0.7 3 64.8 4.4 3.2 7.5 27 7.7 0.3 8.8 0.5

Mackinaw Member

(valley trains)

Rock River 4 47.3 3.6 4.4 203 2.8 7.3 0.1 13.3 0.6

5a 56.8 3.1 32 17.2 2.0 49 TR 12.3 0.4

5b 50 7 2.3 2.1 19.6 2.4 4.8 TR 17.8 0.3

6 50.9 3.2 7.0 18.3 3.2 5.3 TR 11.3 0.8

Fox River 7 63.0 27 4.0 9.7 1.6 10.2 0.1 8.2 0.4

8 66.3 4.3 46 6.5 2.9 6.2 0.1 8.0 1.1

Kickapoo Creek 9 39.9 7.7 85 15.0 5.7 7.3 1.5 13.6 0.7

Illinois River 10 24.0 6.1 6.6 21.1 7.1 4.1 0.2 28.9 2.0

11 39.6 8.1 4.9 14.4 4.2 8.8 1.4 18.4 0.4 12 33.9 9.7 5.7 15.6 4.0 7.9 0.8 22.3 05

Wabash River 13 19.8 9.4 2.0 19.0 5.9 10.3 0.4 32.0 0.8

14 24.6 109 2.3 15.0 5.2 10.2 04 30.4 1.0

15 22.2 94 2.1 21.4 8.2 6.9 0.2 28.1 1.4

Mississippi River 16* 1.7 1.8 0.5 21.7 1.3 2.3 65.3 4.1

'Sample obtained from product stockpile for rock type data only and not subjected to freeze-thaw or other quality tests.

STATISTICAL ANALYSES in comparison with the large number of strongly implicated and metagraywacke The IDOT freeze-thaw expansion unknowns (rock types) per sample. In ad- was weakly implicated in contributing to values for Phase I and Phase II test beams dition, the relatively small number of ex- expansion. were compared (Statistical Analysis Sys- pansive pebbles in the cores of the test Statistical analysis of Phase II data tem (SAS), 1982 a,b) with the respective beams probably increased the variability showed stronger correlations with expan-

Phase I and II sets of rock-type data. and reduced the reliability of the results. sion than did Phase I data; this result can Phase I expansion data were also com- This paper includes only general state- be attributed to the fact that many more pared with IDOT aggregate-quality test ments about the statistical analyses; pebbles were identified, providing more data on the same samples. The General Masters and Evans (1987) contains accurate rock-type percentages, and Linear Models (GLM) (simple regres- detailed data and discussions. many rock types were freeze-thaw tested

sion) and Stepwise Regression (SR) GLM analysis of Phase I data indi- in groups, effectively reducing the num- (multiple regression) procedures of SAS cated that the most abundant rock type, ber of unknowns. were used to determine which rock types dolomite, is not directly related to expan- GLM analysis of Phase U data indi- were related to expansion. sion and that chert, sandstone-siltstone, cated that chert (group I) was the rock Results of the statistical analyses were and limestone may be related to expan- type most strongly related to expansion, often difficult to evaluate or less than sion. Phase I SR data analysis generated even though the chert data were quite conclusive, and therefore must be used a model consisting of the three rock types variable. Samples with total chert con- with caution. One problem was the rela- most likely responsible for expansion. Of tents ranging from about 5 to 22 percent tively small number of samples analyzed these three, chert and ironstone were (25% is the maximum allowed by IDOT

78 nificantly to expansion if present in large Source areas amounts. (figure 3; table 2) Another likely source of the variabil- O McHenry Co. ity in expansion values was the position of D Rock R. expansive pebbles within the test A Fox R beams. As noted in the discussion of # Kickapoo R. Phase I testing, expansive pebbles in the Illinois R. central core of the beam probably con- A Wabash R. tributed the most to freeze-thaw expansion. In any one test beam, the presence of pebbles in critical positions may strongly affect the measured expansion value for that beam. It seems likely that increasing the size of the test beams to the maximum prism size (5x5x15 inches) recommended in ASTM C666-77 would help reduce variability in freeze-thaw data by increasing the overall lithologic representativeness of the pebbles in the beams and increasing the number of pebbles in the central cores of the beams. Dolomite (group 2) content was essentially not related to expansion of the test beam sets (fig. 9). The neutral effect of dolomite in the gravel samples can be further demonstrated by comparing the average expansion of 0.0066 percent for Phase 48 II dolomite (group 2) gravel test beams with that of 0.0060 percent for 83 experimental control test beams containing nonexpansive crushed dolomite (quarry rock).

GLM analysis of freeze-thaw tests of group 3 rock types (table 2) indicated that this rock group contributed only slightly to expansion, and SR analysis identified cherty carbonate and pyritic dolomite as the group members responsible. Because these tests did not identify limestone as a contributor to expansion, it was dropped 30 40 50 from further consideration in this study. Chert and dolomite weight (%) However, this does not mean that other samples containing e ' a*onshi of chert more limestone !5 P and dolomite contents to the average percent respective"V ? expansion of their test beam sets. Each point is would not show increased identified by its sample tSSS?!Sl expansion; it means only that the small amount of limestone in the study standards for gravel samples did not cause aggregate) had ex- gravity of the chert pebbles in the significant expansion. pansions ranging from <0.01 to as much samples. Most individual test beams Neither GLM nor SR analyses as 0.095 percent (fig. 9). Although of test the probably did not contain a lithologically data on group 4 (table positive slope of the 2) indicated any regression line il- representative sample of the 60-pound significant relation lustrates the general relationship of these rocks types to between gravel sample used to make them. IDOT expansion. Therefore, although chert content and expansion, the weakly line specifications restrict the amount of low- should not be implicated as a factor in expansion by the used to predict the expan- specific-gravity (<2.35) chert to less than analysis sion for a of Phase I data, metagraywacke particular chert content. percent 3 of the total sample; however, was dropped The wide range of from further consideration expansion values there may be a direct relationship be- in the study. for the fairly limited range of chert con- tween chert with slightly higher specific GLM analysis tents in the samples suggests of data on group 5 rock that other gravity and expansion. Thus, chert peb- types (table 2) indicated factors besides lithology strongly a surprisingly af- bles with specific gravities near but strong relationship of this fected expansion values. One factor group to expan- was greater than 2.35 may contribute sig- sion. However, this statement probably the wide range in specific must be used cautiously, because many of the rock

79 types in group 5 were absent or occurred n, and the IDOT tests indicated that chert, Expansive pebbles near the surface of only in trace amounts in several samples. especially low-specific-gravity chert, had a test beam may cause popouts without Thus, even though the data for chert are a stronger relationship to unacceptable affecting expansion, but pebbles in criti- more variable, chert is still considered freeze-thaw test expansion than any other cal positions deep within the core of a test more closely related to expansion than rock types. Ironstone was second to chert beam may contribute strongly to expan- are the group 5 rock types. in its relationship to expansion; however, sion without causing a popout. Combined GLM and SR analyses of if ironstone had been as abundant as chert data on the individual rock types in group in the samples, it might have caused the RECOMMENDATIONS 5 indicated that ironstone and silty test beams to crumble. Silty dolomite IDOT and the construction aggregate dolomite were probably most responsible probably caused some expansion. industry should continue to work together for the expansion observed for the group. Weathered carbonate, cherty dolomite, to eliminate the occurrence of D-cracking Other observations concerning cracks pyritic dolomite, conglomerate, sand- in new highway construction pro-jects. and popouts indicated that ironstone was stone-siltstone, shale, and weathered Although freeze-thaw test results are probably more deleterious than silty rocks in general were only suspected to helping to achieve this goal, problems dolomite. Weathered carbonate, con- contribute to expansion. still persist. Additional government- and glomerate, sandstone-siltstone, and shale industry-funded research should be con- may also have been related to expansion, CONCLUSIONS ducted along several lines. but to a lesser degree. Any weathered The following conclusions apply • Test alternate methods of constructing rock type found in other samples in directly only to the high-quality gravel test beams that may eliminate the cause amounts greater than in the study samples sources used in Illinois portland cement of the highly variable expansion values: should be considered suspect, because pavement and to the percentages of the -increasing the dimensions of the test weathering typically weakens rocks, in- rock types found in the study samples. beams from 3x4x 1 5 inches to the max- creases their porosity and permeability, They should not be applied directly to imum recommended size of 5x5x15 and thus may make them more suscep- gravel sources used in other states or inches (ASTM, 1979, C666-77) or tible to expansion. In general, any gravel gravels containing percentage ranges of constructing cylinders 15 inches long samples containing more group 5 rock rock types that differ from those of the with 5.6-inch diameters; this would in- types than the study samples could ex- study samples. crease the number of pebbles in the perience more expansion. Statistical analyses of the Phase I, beams or cylinders, which should give GLM comparison of IDOT aggregate- Phase II and IDOT test data indicated that a more representative population of quality test data with average expansion (1) chert, especially low-specific-gravity rock types in the central core of each

values of the Phase I test beams revealed (<2.35) chert, is related to expansion; (2) beam or cylinder. that the relationship of the individual test ironstone and to a lesser extent, silty -experimenting with different ways of results with expansion ranged from very dolomite, probably cause expansion; (3) embedding the measuring pins in the strong to unrelated. Even very small weathered carbonate, cherty carbonate, beams to minimize the effects of ex- amounts (0.2% to 2.9%) of low-specific- pyritic dolomite, sandstone-siltstone, panding pebbles near their heads. gravity (<2.35) chert were strongly re- conglomerate, shale, and other weathered -eliminating the +3/4-inch size-frac- lated to freeze-thaw expansion. The rocks are only suspected to contribute to tion from materials used to make test IDOT tests for total chert, specific gravity freeze-thaw expansion; and (4) dolomite, beams. This size-fraction contains far of the total sample, and high-specific- igneous rocks, and metamorphic rocks too few particles to provide a gravity (>2.35) chert showed a fairly are not associated with expansion. lithologically representative sample in strong relationship to expansion. These Very small amounts of certain expan- each beam; in addition, the larger IDOT tests on chert further confirmed our sive rock types, most notably low-speci- deleterious particles may have dis- findings that chert has a stronger relation- fic-gravity chert ranging from 0.2 to 2.9 proportionately large effects on ex- ship to expansion than any other rock weight percent, and ironstone ranging pansion. type. from a trace to 1.5 weight percent, can • Determine if the effects of internal The percentage of soft and unsound cause significant expansion. cracking of the beams caused by the materials in the samples (determined by Variability in expansion among test freeze-thaw test can be measured by IDOT) did not correlate well with Phase beams of the same sample and among dif- another method, such as sonic reso- I expansion data, despite the fact that the ferent samples from the same source is nance or electrical resistivity, rather soft and unsound category contains probably related to inconsistent positions than by measuring the length of the test ironstone, an expansive rock type. This and nonrepresentative amounts of expan- teams. lack of correlation was probably due to sive pebbles within the cores of the test • Determine the varieties or specific- the fact that the proportion of expansive beams. gravity ranges of chert that are most sus- to nonexpansive rock types in the Cracks in expansive pebbles (espe- ceptible to freeze-thaw expansion. A category was unknown. Other IDOT test cially chert pebbles) commonly extend- series of freeze-thaw tests could be per- results indicated little or no relation to ing into the surrounding matrix cement formed on beams containing identical freeze-thaw expansion. and through innocuous pebbles were the amounts of chert, separated according To summarize, although there are only abundant deterioration features to ranges of specific gravity and studied petrographically before and after test- problems with the statistics, the results of found during petrographic study of slabs ing. GLM and SR analyses of Phase I, Phase cut from the Phase I test beams.

80 • Determine if the number of beams crete Research Institute, Skokie, IL, Pettijohn, FJ., 1957, Sedimentary tested per gravel source rocks, can be in- Report no. OHIO-DOT- 11 -74, 182 p. 2nd ed.: Harper & Brothers, New creased to compensate for the variabil- Lineback, J.A., 1979, Quaternary de- York, NY, 718 ity of the expansion values, thus raising p. posits of Illinois: Illinois State Geo- Pirsson, L.V., and A. Knopf, 1947, the statistical significance of the data. Rocks logical Survey map (scale, 1:500,000). and rock minerals, 3rd ed.: • Determine if certain gravel processing John Wiley Lineback, J.A., 1981, Quaternary de- & Sons, Incorporated, New York, techniques, such as the use of the verti- NY, posits of Illinois: Illinois State 349 p. cal impact crusher, can eliminate signi- Geological Survey map (scale, Stark, D., ficant amounts of expansive rock 1976, Characteristics and types. 1:2,500,000). utilization of • Determine if significant variations coarse aggregates as- in Masters, J.M., 1983, Geology of sand and sociated with D-cracking: rock types exist in different parts of a pit Portland gravel aggregate resources of Illinois: Cement where samples show extremely variable Association, RDO47.01P. Dlinois State Geological Survey, Il- expansion values. Reprinted from Living with marginal linois Mineral Notes 88, 10 p. Ex- aggregates, 1976, STP597, American tracted from Goodwin, J.H., and J.M. REFERENCES Society for Testing and Materials, Masters, 1983, Geology of aggregate American Society for Testing and Philadelphia, PA, p. 45-58. resources of Illinois: in Ault, C.H., and Materials, 1979, Standard Statistical Analysis System, 1982a, test method G.S. Woodard [eds.], Proceedings of User's Guide: for resistance of concrete to rapid Basics: SAS Institute the 18th Forum on the Geology of In- Incorporated, freezing and thawing: Annual Book of Box 8000, Cary, NC dustrial Minerals: Indiana Geological 921 ASTM, Philadelphia, PA, Part p. 14, Survey, Occasional Paper 37, p. 61- Statistical C666-77, p. 383-388. Analysis System, 1982b, 90, Bloomington, IN. User's Bates, R.L., and J.A. Jackson Guide: Statistics: SAS Institute [eds.], Masters, J.M., and R.D. Evans, 1987, Incorporated, 1980, Glossary of geology, 2nd ed.: Box 8000, Cary, NC Geologic characteristics of American Geological Illinois 584 p. Institute, Falls gravel deposits affecting IDOT Traylor, M.L., Church, VA, 751 p. 1982, Efforts to eliminate freeze-thaw test results: Illinois State D-cracking Dolar-Mantuani, L., 1983, Handbook of in Illinois: Transportation Geological Survey Contract/Grant concrete aggregates, a petrographic Research Record No. 853, Transporta- Report 1987-1, 84 p.; Illinois Depart- tion and technological evaluation: Noyes Research Board, Washington, ment of Transportation Project IHR- DC, 9-14. Publications, Park Ridge, NJ, 345 p. p. 416. Willman, H.B., Klieger, P., G. Monfore, D. Stark, and W. and J.C. Frye, 1970, Moorhouse, W.W., 1959, The study of Pleistocene Teske, 1974, D-cracking of concrete stratigraphy of Illinois: Il- rocks in thin section: Harper & Row, pavements in Ohio: Portland Cement linois State Geological Survey Bul- New York, NY, 514 p. Association, Research and Develop- letin 94, 204 p. ment Laboratories, Cement and Con-

The Chicago Stone Industry: A Historical Perspective

Donald G. Mikulic Illinois State Geological Survey Champaign, Illinois 61 820

ABSTRACT

For more than 150 years, local deposits ofSilurian dolomite have provided essential construction materials for the Chicago area. Lime and building stone were the major construction materials from the days ofpioneer settlement until the turn of the century. In the early years, many local exposures were quarried, regardless ofrock quality, to compensate for a poor and expensive transportation system As canals, railroads, and roadways were built, however, higher quality rock became more accessible. The opening ofthe Illinois and Michigan Canal in 1848 allowed shipping of high-quality building stone from Lemont, Lockport, and Joliet to Chicago and other major markets. Quarries in high-purity dolomite closer to Chicago specialized in the production of lime during the latter half ofJ the 19th

century. . Around the beginning the 20th of century, economic conditions, changes in construction methods, importation of superior-quality stone, and production and marketing ofconcrete blocks caused the permanent collapse ofthe local building- stone industry. The use cement also of eliminated the major market for locally produced lime used as mortar. These events resulted in the abandonment ofmany quarry sites and the disappearance of several of the larger stone producers in northeastern Illinois. Early in this century, crushed stone for aggregate became, and still remains, the primary product of the local stone industry. Consolidation of many small independent operators into the major producers that dominate the industry today coincided with this development. Geologic constraints and urban expansion continue to place severe HOLOCENE and WISCONSINAN andfinite limits on crushed stone reserves in the Chicago6 Metropolitan area. Alluvium, sand dunes, and gravel terraces INTRODUCTION WISCONSINAN industry have been discussed in several Since early pioneer settlement, the lake deposits papers (Mikulic and Goodwin, 1986; local stone industry has figured pro- Mikulic and Kluessendorf, 1985; Mikulic WOODFORDIAN minently in the development of the et al., 1985; Willman, 1971, 1973). The moraine Chicago metropolitan area. Here as else- availability of stone is limited primarily where, the availability of stone affected by the distribution, thickness, and com- front of moranic system the cost, style, amount, and quality of position of unconsolidated Quaternary local construction. Whereas geological ground moraine sediments that cover most of the bedrock features and access to the resource con- surface in ALTON IAN northeastern Illinois (fig. 1). strain the availability of stone products, These sediments generally are too thick changes in till plain economic trends, transporta- to remove economically in order to ex- tion, architecture, and technology affect ploit the underlying bedrock. Rock is ex- Figure 1 Glacial geology the of northeastern Il- demand for and use of stone. The in- posed or near the ground surface in linois (after Willman, 1971). teraction only of these factors is outlined in a few areas, primarily where stream or this brief history of the stone industry in lake erosion has removed most of the the Chicago The character and distribution of area, encompassing Cook, sediment the (fig. 2). Numerous exposures bedrock Will, Du Page, have played an important role in Kane, Lake, McHenry] along the Des Plaines, Kankakee, and the and Kankakee Counties. availability of stone materials. Silur- Fox River valleys are the result of stream ian dolomites underlie all of the Chicago erosion, whereas exposures in eastern region GEOLOGY except the western edge (fig. Cook County 3). are Silurian reef-controlled The composition The geological features of the Chicago and thickness of these bedrock hills uncovered by lake erosion. dolomites vary from east area and their influence on the local stone to west across the region as the rock dips eastward at 10

83 \ —

to 15 feet (3.0 to 4.5 m) per mile (km) A B (fig. 4) (Willman, 1971). Silurian rocks F- 14 SSC-1 SSC-2 DH71-56 DH-15 are thickest (500 ft; 150 m) along the

Lake Michigan shore and in eastern Will ^~"~- drift and Kankakee Counties. The base of - -| T~" V strata rises these towards the west and the . |

1 \ *» \ entire Silurian thins because of erosional N. HNk. s \ \ \ 7'V \n 1 truncation. Along the western edge of the elev / v

500 ft study area, Ordovician rocks are exposed n. Silurian ! h- 1 1 where the Silurian has been eroded com- L ra i \ ^x 1 1 pletely. Ordovician strata also rise to the \ -i i •v. west \ CO J and are thinned by erosion. I

1 i r— Silurian strata are classified into Galena\ -j, v Xs^ j m several stratigraphic units on the basis of \. Gp Maquoketa \Gp general lithologic characteristics (fig. 5). These characteristics determine the use- c TO c, Ancell O \ '— > J v Gp N. O w Prairie du Chien ^PlattevilieX -o Gp \Gp O 100 r-

I 1 20 mi

Figure 4 Diagrammatic cross section of Paleozoic rocks from west to east in study area, showing westward truncation of Silurian strata and general eastward dip of rock units toward the Michigan Basin. Boreholes F-14, SSC-1, SSC-2 are based on core logs obtained by the ISGS as part of the siting study for the proposed Superconducting Super Collider. Boreholes DH71-56 and DH-15 are based on core logs from the Metropolitan Sanitary Dis- trict of Greater Chicago obtained during planning for the Chicago Tunnel and Reservoir Plan. The bedrock surface at DH-15 has been extended up to an elevation of 600 feet to show the nature of nearby Stoney Island, a reef-con-

trolled bedrock hill.

(100 m) in places; it forms the bedrock surface throughout much of the eastern half of the study area. In general, the Racine varies from argillaceous to pure

dolomite. The unit is thickest in the eastern part of Cook County where large, high-purity dolomite reef structures occur, accounting for most of the Silurian Figure 2 Outcrop distribution in the Chicago exposure in this area (fig. 2). Their region (modified from Willman, 1971). proximity to the center of the city and fulness of each unit for various stone their high purity always have made the products. During the 19th century, PENNSYLVANIAN Racine reefs the most desirable north- limited amounts of flagstone, rough eastern Illinois source of many stone building stone, and lime were produced SILURIAN products, including lime, riprap, ag- from all parts of the Silurian. The use of gregate, foundation stone, and flux. these products depended less on rock Underlying the Racine is the Sugar quality ORDOVICIAN than on proximity of the exposure Run Dolomite (fig. 5), which is as thick the to building site. Ultimately, however, as 30 feet (9 m). The Sugar Run is ex- improved transportation and higher rock- Q Des Plaines Disturbance posed primarily along the Des Plaines quality requirements resulted in greater (Ordovician to Pennsylvanian) River valley in the vicinity of Lemont and selectivity. Joliet (fig. 2), where it forms the bedrock Figure The Racine Dolomite, the uppermost 3 Bedrock geology of northeastern surface in places. This well-bedded, linois (after Willman, 1971). Silurian unit (fig. 5), is as thick as 300 feet

84 even-textured rock was the major source of building stone in the late 19th century. The Joliet Dolomite (fig. 5) underlies the Sugar Run Dolomite. The Romeo Member at the top of this unit consists of up to 35 feet (10.5 m) of high-purity dolomite similar in appearance and character to Racine reef rock. The Romeo Member has been used for lime and flux around the towns of Joliet and Romeo- ville. The underlying argillaceous and thick-bedded Markgraf Member, as much as 28 feet (8.5 m) thick, also has been used for building stone. The remaining Joliet Dolomite, the Kankakee, Elwood, and Wilhelmi For- mations (fig. 5) that constitute the lower 100 to 200 feet (30 to 60 m) of the Silurian, generally consist of thinbedded, argillaceous dolomite. This part of the Silurian is well exposed along the Fox River valley in Kane County, in western and southern Will County, and along the Kankakee River in northwestern Kankakee County. Active and abandoned quarries are numerous in these areas, but variable stone quality, decreased thickness of this part of the Silurian, and distance to the Chicago market make these areas less desirable for quarrying than sites farther east. Shale belonging to the Ordovician Maquoketa Group (fig. 5) ranges from 100 to 250 feet (30 to 85 m) in thickness. It underlies the Silurian strata throughout the study area except in the western part of the Chicago metropolitan area, where it occurs at the bedrock surface (fig. 3). The thin (0 to 30 ft; to 9 m) Fort Atkin- son Limestone is the only part of the Ma- quoketa that has been quarried in this region. Maquoketa strata are generally too thick to remove economically in order to exploit dolomite and limestone of the underlying Ordovician Galena Group (fig. 5), which is exposed only in Kendall County and farther west. As thick as 200 feet (60 m), the Galena is a rarely utilized source of aggregate that lies beneath the entire Chicago region. However, underground mining of the Galena has become economically feasible at one location in Du Page County, and the Galena is potentially a very large, high-quality source of aggregate and subsequent underground storage space.

C°' Umn Sh0Win9 SHUrian and °rdovician rocks MikuHc hSFvSbF in northeastern Illinois (after

85 GROWTH OF THE BUILDING STONE INDUSTRY 8TGKTE DB.3SS8EXLS. When pioneer settlement of the region began in the early 1800s, construction m"Mlzwm tm §1111111, materials such as lumber, brick, building and foundation stone, and lime for mortar had to be obtained locally because of the severely limited and expensive %\t lllhtois State fajpjj, transportion system. Although the nearest exposures were located several miles from the center of ORGANIZED FEBRUARY S4, 1855. the original Chicago settlement during the 1830s to the 1850s, quarries had been Chicago Office, - Corner Wells and Taylor Streets. opened in many of the low exposures of President S. F. Gale. TST7STEB8. Racine reef rock on the Lake Chicago Treasurer H. O. Loomis. S. F. GALE, W. S. GTJBNEE, Plain (figs. 1, 2). The earliest document- Secretary and Superintendent. .. J. Vf. McGenniss. H. G. LOOMIS, A. 8. SHERMAN, General Agent A. S. Sherman. O. SHERMAN. ed stone production occurred in 1833 The ILLINOIS STONE COMPANY is bow prepared to contract for the delivery when a quarry was opened in what is now of Stone from its celebrated quarries at "Athens." the Bridgeport neighborhood of Chicago. For beauty and uniformity of color, this stone stands unsurpassed by any in the United States. Stone from this quarry was towed in bar- The Company's facilities are ample for furnishing any desired quantity of Dimension, Block, Rubble Stone. ges 4 miles along the South Branch of the or Orders through the Post office or left at the office of H. G. Loomis, Treasurer, 8 Clark street, Chicago River to Lake Michigan and was up stairs, addressed to the undersigned, will receive prompt attention. used in the original construction of the J. W. McGENNISS, Superintendent Chicago Harbor pier (Andreas, 1884). Stone was readily accessible near Figure 6 Advertisement for the Illinois Stone Company from the Northern Counties Gazeteer and Directory for 1855-56, Joliet and other settlements along rivers Robert Fergus, Book and Job Printer, 1855. and streams and was used in many early ing material used in many major residen- Major consolidation of the industry local building projects. Shepard (1838) ces, businesses, government buildings, took place in 1889 when Singer and Tal- mentioned that Chicago quarries were and churches, and extensive quarries cott combined with five other building- producing "a valuable flagging-stone," were opened at Lemont in the early 1850s stone companies, forming the Western whereas quarries at Joliet were extracting by the Singer and Talcott and the Illinois Stone Company (fig. 7) (Goodspeed "very valuable building material." These Stone companies (fig. 6). Publishing Company, 1891). This new quarries were small, labor-intensive, in- During the late 1800s, Lemont-Joliet company employed about 1500 men and termittent operations that generally were building stone was the major product of operated 35 boats, tugs, and barges at its worked only to supply construction the stone industry in northeastern Illinois. Joliet, Lemont, and Chicago yards materials for a specific project. Singer and Talcott, the largest building (Goodspeed Publishing Company, 1891). The rapid development of Chicago in stone producer throughout much of this the middle late and 1800s created a major period, employed 300 workers at its DECLINE OF THE BUILDING market for stone products, and a con- Lemont quarries and 150 at its Chicago STONE INDUSTRY tinually improving transportation system yard (Land, 1883). Despite continued growth of the build- permitted the economical and reliable Increasing amounts of Lemont-Joliet ing-stone industry through much of the shipment of stone materials to this stone were shipped outside northeastern late 1800s, several problems that arose market. In 1847, stone from Joliet was Illinois as an extensive railroad network led to its total collapse by World War I. hauled by wagon to Chicago for construc- developed throughout the Midwest. In The first problem concerned a change in tion of Scammon School (Goodspeed the 1860s, W. A. Steel's quarry, located the way large buildings were constructed. Publishing Company, 1891). The Illinois between Lockport and Joliet, supplied Massive stone blocks had been used as a and Michigan Canal, which opened in stone for government construction foundation to support most of the weight 1848, was the most important advance- projects in Illinois, Wisconsin, Missouri, of a building, but during the 1870s steel ment in transportation for the stone in- Iowa, and Indiana (Steel, 1871). In 1870, internal supports came into use, eliminat- dustry because it provided a direct and Joliet quarries produced 1,125,000 cubic ing the need for stone foundations. As inexpensive means of shipping building feet (12,000 railroad carloads) of stone this type of construction became more stone from Joliet, Lockport, and Lemont and employed 700 men (Steel, 1871). By widespread, stone was relegated to an or- to the Chicago market. 1886, building-stone quarries were lo- namental function, primarily as veneer; The closest source to Chicago of well- cated at many communities; those listed such use placed more emphasis on the ap- bedded, high-quality Sugar Run Dolo- by Polk (1886) include: Aurora (2), pearance of the stone facing and less on mite (then known as Athens, Lemont, or Batavia (6), Bonfield (1), Joliet (15), the quality of the rock. Joliet limestone) was discovered during Kankakee (1), Lemont (5), Naperville By the 1890s building stone was being construction of the canal itself at Lemont (2), and Sag Bridge (1). Undoubtedly, imported from outside the area, con- (then called Athens). During the late more quarries existed. stituting another problem for the Le- 1800s this stone became a popular build- mont-Joliet stone industry. Improved

86 However, the lime industry eventually suffered a fate similar to that of the building-stone industry, for some of the same reasons. Like the building-stone industry, the manufacture of lime was affected adversely by an increase in the use of cement. Although lime is still produced at the Thornton and McCook quarries, most quarries abandoned its production early in this century.

CRUSHED STONE PRODUCTION With the development of a more extensive and enduring transportation system, crushed stone, utilized mostly for macadamizing roads C°mpany Perati°nS at Lemont and for railroad bal- ° 1907 i by E. ' P^to F. Burchard! U.S SlSiL^S; last, became an important product of the mid- transportation methods to late 1800s. Large-scale mac- permitted a The Chicago area quarries did produce adamizing, beginning variety of stone types such as Lake in the 1860s, led to Supe- some building stone. However, local rock the formation of the rior sandstone from Michigan and Wis- Dolese and Shepard seldom could be excavated in consin, large slabs, Company in 1868 by John granite from Wisconsin, and did Dolese and not have an acceptable appearance,' limestone Jason Shepard (Goodspeed from Indiana to be sold com- and was Publishing more difficult to fashion into Company, petitively with local building 1891). Dolese and Shepard stone in the blocks than the stone at the Lemont-Joliet operated a number Chicago market. Labor and economic of quarries in Cook quarries; therefore, it could never com- County; in 1870, the problems during this period also company employed had a pete with the latter for the building-stone 600 men at its negative impact on the industry. Hawthorne and Chelten- market. Some of the Racine Dolomite ham Another critical quarries and an additional 200 factor in the decline of from the men Rice and Artesian quarries near for the Lemont-Johet street construction. stone industry was the Grand and Campbell streets in Chicago By the late increasing use of concrete in 1800s, many of the older construc- contained asphalt-filled pores and was quarries that had tion. Concrete now could be used initially been located to marketed as "blackstone." This produce a stone in rural areas were surrounded more uniform, durable, and ul- was by resi- used in such buildings as the Second timately cheaper dential neighborhoods, and there building material than Presbyterian was no Church and the castellate natural stone. room for lateral expansion. The Sidewalks, previously con- walls and only towers of the Libby Prison- recourse structed of large slabs of was to quarry to greater depth; cut or rough Coliseum in Chicago. stones, however, strata beneath had provided a major market for the Racine stone Dolomite in Cook County in Chicago; now, stone slabs were LIME PRODUCTION generally are rapidly unsuitable for high-quality being replaced by uniform slabs lime. During the rise and fall of the Lemont- of Crushed stone for street concrete. Rough and cut foundation paving and con- Joliet building-stone industry, lime-burn- stone was replaced crete aggregate therefore became by cheaper, more ing continued the to be a major part of the main durable, and uniform product of many older quarries. concrete blocks. Chicago area stone industry. Although The advent of Old habits died hard, however, and many Cook crushed-stone production County operations, which quarried marked early concrete blocks were the beginning of the modern molded to high-purity Racine Dolomite, look were the Chicago stone industry. like dressed stone. The only build- main source of lime, kilns were also ing-stone market As city quarry sites were exhausted, remaining was orna- operated at Kankakee, Batavia, Joliet, the mental stone, for extensive Chicago railroad network which most of the local and elsewhere. Several prominent com- provided Silurian rock was not well cheap transportation of crushed suited. panies, including Stearns Lime and Stone stone into the city By World War I, the once center from outlying prosperous and Chicago Union Limeworks, Lemont- were regions, primarily the Joliet building-stone industry formed Thornton and Mc- in and around Chicago to take ad- had almost disappeared. Cook areas. With the development of Since that time vantage of this high-quality rock close to these two some cut stone has been produced from outlying districts and exhaus- the city market (Mikulic and Kluessen- Silurian rocks in tion of high-purity reserves, northeastern Illinois, but dorf, most of the 1985). The demand for lime ap- Chicago only a few flagstone quarries remain quarries closed down; by 1930, in parently far exceeded the the capacity of only the Stearns once extensive Lemont-Joliet quarry quarry at Bridgeport local kilns, and from the 1860s district. through remained (Mikulic None of the major building-stone the and Kluessendorf, 1890s, a number of Wisconsin firms concerns, even 1985). Formation of the those that were the largest maintained Material Service offices in Chicago where they companies in Corporation by the Crown family the Chicago stone industry sold lime in 1917 that was similar if not identical for several decades, and expansion of the Consumer survived this col- to that Com- produced in the local quarries. lapse. pany in 1921 led to major consolidation of the crushed-stone industry. The Dolese

87 Figure 8 Abandoned stone quarries in northeastern Illinois. Figure 9 Active stone quarries in northeastern Illinois. and Shepard Company, long the largest Goodwin, 1986). The northeastern Il- these localities would not be a promising Chicago area stone concern, ended near- linois stone industry is faced with the source for the future. ly 100 years of operation when it was ac- problem of securing new long-term sour- When the few remaining quarries quired by the Consumer Company (now ces of local stone to meet the increasing eventually close down, stone for Chicago Vulcan Materials) in 1967. demand of the growing metropolitan area needs will have to be imported from With industry consolidation, urban ex- area. This growth has created and main- more distant areas at increasingly higher pansion, and increasing demand for tained an enormous market for stone transportation costs. An alternative solu- higher-quality materials, the number of products, but at the same time has tion may be underground mining of the quarries in northeastern Illinois has eliminated many local sources of such Ordovician Galena and Platteville decreased dramatically since the turn of materials from exploitation. Urban ex- Groups at existing quarry sites, as is now the century. More than 250 abandoned pansion has limited the number of poten- done at Elmhurst-Chicago Company's

stone pits are known in northeastern Il- tial quarry sites in areas where the Elmhurst plant (fig. 9). Quarries such as

linois (fig. 8), but only about 20 sites are Silurian is thick and consists of high- those at McCook and Thornton would be quarried today (fig. 9). quality Racine Dolomite. Localities in particularly suitable for this approach be- the western part of the metropolitan area cause of their large size. STONE INDUSTRY PROSPECTS are available for quarrying, but the thin Most of the once-rural quarries are section of Silurian rock in this region and REFERENCES now surrounded by urban development; the poorer quality of stone produced from Andreas, A. T, 1884, History of Cook

tittle room exists for expansion, and near- some lower Silurian units suggest that County, Illinois: A. T. Andreas, Pub- surface reserves are limited (Mikulic and lisher, 888 p. Goodspeed Publishing Company, In- Chicago area. Forty-Ninth Annual Steel, W. dustrial Chicago, 1891: The building A., 1871, Stone, in H. Rowell, Tri-State Field Conference, interests, Trip 2, The 816 p. great resources and superior University of Illinois-Chicago, ad- Land, J. E., 45 p vantages 1883, Chicago: The future of the City of Joliet, Illinois: Mikulic, D.G., M.L. Sargent, R.D metropolis of the new Republican Steam Press, world: City of Norby, and D.R. Joliet, IL Chicago. Kolata, 1985, Willman, H. B., 1971, Summary of the Silurian geology of the Mikulic, D.G., Des Plaines geology of and J. Goodwin, 1986, nver the Chicago area: Illinois valley, northeastern Illinois: Urban encroachment Illi- State Geological Survey on dolomite nois State Circular 460 Geological Survey Guide- 77 resources of the Chicago, Illinois, p. book 17, 56 p. area; Twentieth Willman, H. B., Forum on the Geology Polk, 1973, Rock stratigraphy R. L., and Company, 1886, of Industrial Illinois of the Silurian System Minerals: Industrial State in northeastern Gazeteer and Business Direc- and Minerals of the Mid-Atlantic northwestern Illinois: States, tory, v. 6. Illinois Glaser, State Geological J. D„ and J. Edwards [eds.l, Shepard, Survey Circular 479, C. H., 1838, Geology of upper p. 125-131. 55 p. Illinois: American Journal of Science Mikulic, D. G., and J. Kluessendorf, ser. l,v.34,no. l,p. 134-161. 1985, Classic Silurian reefs of the

An Overview of the Geology of Clays, Shales, and Slates Utilized in Ceramic and Structural Clay Products in Georgia

Bruce J. O'Connor Georgia Geologic Survey 19 Martin Luther King, Jr. Drive, SW Atlanta, Georgia 30334

shale) in Georgia ABSTRACT and their ranking in value and tonnage with respect to the total Since the turn of the century, a national production. wide variety of argillaceous materials have Kaolin is clearly the ^en used m the manufacture ceramic predominant clay of and structural clayproducts in Georgia commodity mined in In the Valley and Ridge and the the state. However, Cumberland Plateau Provinces in northwest common clay and Georgia, widespread deposits shale, as well as of clay and shale consist mostly of weathered fuller's earth, also make Paleozoic shales but also include a substantial Tertiary to Recent alluvial, colluvial and contribution to the total clay residual clays and Paleozoic slates and output. Nationwide, phyllites. Presentproduction comesprin- Georgia ranked fifth cipallyfrom Cambrian, Silurian, and Mississippian in production (tonnage) illitic shales that are used for but eighth in common brick and quarry tile. Ordovician value of common clay slates are used for lightweight ag- and shale among gregate. In the past, other products such the 43 clay and shale as sewer pipe, flue tile, fire brick roof- producing states. 8 65 portland cement (Texas and North '?"? "ere produced locally in northwest Georgia Carolina ranked first Muchm TILthe of shale mined in this area is shipped and second in common clay to plants in other parts ofthe state production in and in adjacent states. 1985.) In the Piedmont and Blue Ridge Provinces, common brick, flue tile and Portland cement are manufactured GEOLOGY from Quaternary alluvial clays and/or saprolitic residuum developed Georgia is divided on the Precambrian to Paleozoic bedrock into five physio- (weathered slate, phyllite, phyllonite, graphic provinces (fig. and fine-grained schist). In the Coastal 1) that can be PlamProvince, common brick isproduced grouped into three major from Quaternary alluvial and colluvial geologic areas clays along the major river flood (Georgia Geological plain systems adjacent to metropolitan areas Survey, 1976). along the Fall Line These From north to south alluvial deposits are similar to but more widespread these are: the Cum- than those in the other provinces. They all contain berland Plateau and Valley and mixtures ofkaolinite illite Ridge smectite, chlorite and vermiculite Provinces in northwest and are commonly blended with clay and/or Georgia; the Blue shalefrom the other provinces. Tertiary Ridge and Piedmont Provinces kaolinitic clays and smectitic clays are in north central ctn*M Li Georgia; and the Coastal Plain 7*** *"**!* ' S^eight aggregate has been ZllZ % - P Paleocene smecnte and chlorite-bearing Province in south Georgia. The pre- h fl clay in southwest Geor- gia,2 but this operation is not currently dominant features of each active. In the past, other products such as of these areas sewer pipe, structural tile, and are summarized in table roofing tile were also produced in the Coastal 2. Northwest Georgia The INTRODUCTION Cumberland Plateau and the Val- three major ley clay commodities (kaolin, and Ridge Provinces of northwest Many geologists are aware of the fact fuller's earth, and common clay and Georgia consist predominantly of folded that Georgia is a major producer of kaolin Paleozoic sedimentary and rocks (mostly car- fuller's earth; however, most do not realize that Table Clay a substantial amount of com- 1 production in Georgia for 1985*. mon clay and shale is also produced in the state. This article summarizes informa- National rank tion on the geology, commercial utiliza- Type Tons(x106 6 ) Value ($)(x10 tion, ) Tonnage Value and historical development of these common clay and shale deposits. Kaolin 6.3 535.0 Table 1, which shows the total clay Fuller's earth production in 0.6 34.6 Georgia for 1985, is based on the Common most recent data available from the 1.7 5.5 U.S. Bureau of Mines (Ampian, 1987; White and Total O'Connor, 1987). This table il- 8.6 575.1 lustrates the relative importance of the *Data from Ampian, 1987.

91 Cumberland Plateau were used in making brick, tile, sewer pipe, and flue liner. In several areas, Ter- tiary siliceous and kaolinitic residual clays derived from Cambrian-Ordovician Knox Group carbonates were used in making fire brick. Residual clay of the weathered Rockmart Slate (Ordovician) has been used in the production of Portland cement, and slates of the Con-

Augusta asauga Group (Cambrian) at one time were crushed for roofing granules.

Blue Ridge and Piedmont The Blue Ridge and Piedmont Provin- ces are composed of igneous and metamorphic rocks (mostly gneisses, schists, and granites) that range in age from Precambrian to Paleozoic. Much of the bedrock in this area is blanketed with a thick residual clay mantle (saprolite), and Quaternary to Recent alluvium is commonly thick along the major streams and rivers in this area. Common brick, flue tile, and portland cement are locally manufactured from these alluvial and saprolitic clays, which can be improved by blending with clays from northwest Georgia. In most cases, the preferred saprolitic clays are those derived from relatively fine-grained argillaceous bed- Figure 1 Physiographic provinces of Georgia.

Georgia. bonates, sandstones, and shales) ranging Table 2 Structural clay deposits of from Cambrian to Pennsylvanian in age. Province Age Type Clay Minerals Use They are essentially unmetamorphosed except along the eastern and southern Cumberland Paleozoic Shale lllite Brick, tile, quarry border of the area where slaty cleavage is Plateau and tile and pipe (cement) well developed. In this region the Valley and Ridge Paleozoic Slate lllite, chlorite Lightweight, aggregate Paleozoic strata have been overthrust by (roofing granules) the igneous and metamorphic rocks of the Blue Ridge Province along the Great (Tertiary)* (Clay) (Kaolinite) (Firebrick) Smoky-Cartersville Fault. (Quaternary (Clay) (lllite, chlorite, (Brick, tile, pipe, and Clay and shale deposits have been to Recent) smectite, kaolinite flue liner) mined from a number of stratigraphic and vermiculite) units in this area. For the most part these are illitic lithologies that are best utilized Blue Ridge Paleozoic Weathered lllite, chlorite, Brick, cement, and in the manufacture of structural clay and Piedmont and phyllite and and kaolinite flue liner products such as brick, tile, and sewer Precambrian? phyllonite pipe. The most important of these residuum lithologies are the shales (and residual Quaternary Clay lllite, chlorite, smec- Brick, flue tile, clays weathered from them) of the Con- to Recent tite, kaolinite and and cement asauga Group (Cambrian), the Red vermiculite Mountain Formation (Silurian), and the Floyd Shale (Mississippian)—all used in Coastal Plain Quaternary Alluvial lllite, chlorite, smec- Brick (pipe) tite, kaolinite and making brick and/or quarry tile. In addi- and Recent clay vermiculite tion, the Rockmart Slate (Ordovician) is expanded for lightweight aggregate. Tertiary Clay Smectite and Cement and light- In the past, various products were chlorite weight aggregate produced from other local deposits. Tertiary Clay Kaolinite Cement Quaternary to Recent alluvial clays mined from many of the local flood plains 'Items in parentheses indicate deposits no longer being worked and types of clay no longer used.

92 rock such as slate, phyllite, phyllonite, detrital mica, quartz silt, and and organic cialized applications such fine-grained mica schist. However, in as coatings, debris. They are commonly blended with some fillers, absorbents, and catalysts. places brick was made from clay and/or shale from other areas. residual and colluvial clays derived from Relatively little common clay has HISTORICAL gneissic bedrock, and saprolite DEVELOPMENT clay been mined further to the developed south. Common clay has been on a small gabbro body was Lightweight mined in aggregate was produced Georgia for the blended with other clays manufacture of building to make sewer from carbonaceous clays of the Tus- brick since at pipe. cahoma least the late 1700s (Smith, Formation (Paleocene) for a 1931). However, very little comprehen- short period Coastal Plain of time in Clay County. sive information is available on clay Kaolinitic min- The clays (Eocene undifferen- ing and Coastal Plain occupies the south- production of structural clay tiated) and em half fuller's earth of the Twiggs products of the state and is composed of that occurred before early in the Clay (Eocene) in Houston County poorly consolidated sediments—mostly are 20th century. used in clays, making portland cement; Shortly sands, and marls ranging in age after the turn of the century, however, most of the clay mined south from Cretaceous to Recent. The northern of common clay and shale were mined the at boundary Fall Line is high-grade kaolin and numerous of the Coastal Plain is called the locations that were, in general, fuller's Fall Line; earth, which are used in more spe- evenly this is the surface expression of distributed among the three areas the unconformity between the igneous and metamorphic rocks of the Piedmont and Blue Ridge and the overlying Coas- tal Plain sediments. Common Quaternary alluvial deposits are • and pavina well brick developed along the major stream and Sewer river flood plains pipe, rooting across the Coastal and drainage tile Plain. This alluvium is extensively mined A Fire brick for commercial brick clay adjacent to major metropolitan centers near the Fall Augusta Line. These clays are composed of mixtures of kaolinite, illite, smectite, chlorite, and vermiculite with varying amounts of

' - • 2

^loi*e

Columbus Figure 2 Structural clay products in Georgia 1909. Each symbol indicates a county in which a company was producing structural clay products. The number adjacent to a symbol indicates the number of companies producing the commodity $ in that county (based on data from Veatch, 1909).

• Common and paving Figure Structural J? brick 3 clay products in Georgia, 1931 Each symbol . indicates a county in which Sewer pipe and a company was producing drainage tile structural clay products. The number adjacent to a symbol in- A Roofing tile and dicates the number of companies flue liner producing the commodity in that county (based on data from Smith, 1931).

93 Figure 4 Current mining of structural clay and related • Paleozoic clay and shale in indicates county in materials Georgia. Each symbol a O Recent and Quaternary which a company (or companies) is mining the commodity alluvial clay in that county (based on data in Steele and O'Connor, © Tertiary (Eocene and 1987) Paleocene) sedimentary clays

A Paleozoic slate and phyllite

Residuum Figure 5 Structural clay products currently produced in Georgia. Each symbol indicates a county in which a company (or companies) is Augusta producing structural clay products; the number adjacent to a symbol indicates how many companies are producing the commodity in that county.

somewhat more numerous and widespread than the manufacturing plants; the explanation for this is that the most desirable raw materials are not always available close to established plants and that most plants use a blend of several grades of clay in manufacturing their products. O Cement The data summarized in figures 2 to 5 D Lightweight suggest the combined effects of several aggregate factors over time. Near the turn of the century, clay and shale were mined from numerous small pits used mostly to sup- of the state. Figure 2 shows the location Georgia (fig. 3). According to data in ply relatively small plants that generally

(by county) of clay and shale plants Smith (193 1), most of these deposits were served small, local markets. Because producing a variety of structural clay used for brick manufacture, although demand was relatively small, local products in the early part of the century sewer pipe, drain tile, roofing tile, and deposits could easily be found near these (from data in Veatch, 1909). Nearly all of flue liner also were made locally. plants. Over time, many of these deposits these manufacturing facilities used clay Data on current mining of structural were exhausted. In addition, urban and shale mined from local deposits, and clay and related materials and the growth has encroached on many potential most of the plants were producing brick. manufacture of structural clay products reserves, and the increasing popularity of However, at a few locations fire brick was are summarized in figures 4 and 5 (from wood, concrete, and plastic has reduced made from residual and sedimentary data in Steele and O'Connor, 1987). the overall demand for structural clay kaolinitic clays in northwest Georgia and These figures illustrate the continued products. Increased energy costs have along the Fall Line. Other specialized trend of consolidation near the larger forced many older, inefficient plants to products, mainly sewer pipe, drain tile, metropolitan centers of Rome (in close or consolidate with other opera- and roofing tile, were produced at wide- northwest Georgia), Atlanta (in the Pied- tions. ly scattered locations across the state. mont), and near Columbus, Macon, and The net result of these factors is that a By the 1930s, common clay and shale Augusta (along the Fall Line). A com- relatively small number of companies is production was largely concentrated parison of the two figures, however, indi- now producing a limited range of struc- along the Fall Line and in northwest cates that the clay and shale mines are tural clay products from large plants near

94 their market areas. Because of the limited has a broad market base throughout the Georgia Geological Survey, availability of large volumes of clay 1976, Geo- and southeastern United States. In addition, logic Map of Georgia: shale raw materials, some of the clay Georgia Geo- is the ceramic tile market is growing and transported logical Survey, scale 1:500,000. long distances from the mine will probably offset any losses the brick Smith, to the plant. R.W., 193 1, Shales and brick clays industry may experience in the future. of Georgia: Georgia Geological The ceramic Sur- tile industry continues to ex- vey, FUTURE Bulletin 45, 348 p. DEVELOPMENTS press a strong interest in Georgia's struc- Steele, W.M., and Future developments are difficult BJ. O'Connor, 1987, to tural clays, and numerous foreign and Mining directory of Georgia: predict; however, we anticipate contin- domestic Georgia companies have studied the Geologic ued stability accompanied Survey, Circular 2, 92 by a modest area for the possible p establishment of new Veatch, O., growth in the ceramic and 1909, Second report on the structural clay ceramic tile plants in the state. clay deposits of industry in Georgia. Raw materials are Georgia: Georgia adequate Geological Survey, Bulletin 18, 453 and the economy of the state is REFERENCES p. White, D.H., strong. The construction industry Jr., and B.J. O'Connor, is heal- Ampian, S.G., 1987, Clays: U.S. Bureau thy. Although 1987, The mineral industry of Geor- building-brick faces strong of Mines, Minerals Yearbook 1985 gia: U.S. Bureau competition from alternative of Mines, Minerals construc- v. 1, p. 259-294. yearbook 1985, v. tion materials, Georgia's brick industry 2, p. 149-160.

Industrial Minerals and the CUSMAP Program

A. W. Rueff Missouri Department ofNatural Resources Missouri Geological Survey Program Rolla, Missouri 65401

1. Compilation of geologic, ABSTRACT stratigraphic, geochemical, and geophysical maps of a quadrangle Explorationists, geologists, and geological surveys have many to identify for years been known studying mineral deposits and inferred geologic environ- and attempting to extrapolate their findings into mineral resource ments and structures present. appraisals oflarge regions. One such attempt has been the Con- 2. Determination terminous United States Mineral of types of mineral Assessment Program (CUSMAP) of the U.S. Geological deposits that could be expected to Survey. The Missouri Department of Natural Resources, Missouri Geological Survey occur in the quadrangle on the basis of Program, has been involved infour CUSMAP appraisals and is currently (a) known mineral deposits and occur- starting a fifth. The work began with the Rolla 1° x 2° Quadrangle rences in 1975, that exist in the quadrangle and continued through the Springfield, Harrison, and Joplin 1° Quad- rangles, and now includes 1° (b) known worldwide associations of the Paducah x2° Quadrangle. The original intent certain ofthese studies, at mineral deposit types with least that ofthe U.S. Geological Survey, was to evaluate metal- geologic lic mineral resource potentials. environments and structures Over time, because of changing interests the of that mineral industry exist in the quadrangle. and different geologic conditions in various quadrangles, these 3. Development studies have evolved into of descriptive models for more broad-based mineral resource appraisals. In the Rolla Quadrangle, each mineral deposit type. assessment ofa wide range ofminerals was an essential part of the study 4. Development of "recognition criteria" from the beginning. Industrial minerals are the only mineral resources that are currently (based on the descriptive model) for exploited and that have any realistic economic potential forfurther the occurrence or nonoccurrence of development in the Springfield Quadrangle. In the Joplin Quadrangle each type of the appraisal will include mineral mineral deposit. fuel potential. An opportunity exists forfurther development and 5. Careful study of the available data for refinement ofthese appraisals in the upcoming study ofthe Paducah Quadrangle the existence of recognition criteria. for the states ofKentucky, Illinois. Indiana, and Missouri 6. Evaluation of the distribution and importance of various recognition INTRODUCTION criteria to appraise the probability of geologic information about the area occurrence and generalized location The Conterminous United States (Ovenshine, 1982, personal communica- for each Mineral mineral deposit type Assessment Program, common- tion to W. B. Howe). A characteristic of throughout the quadrangle. ly known as CUSMAP, is the result of CUSMAP appraisals, however, is their Recognition criteria, several essential to this long-term U.S. Geological Sur- temporary significance because of methodology, are the geologic charac- vey (USGS) efforts to prepare regional changing economics and technological teristics that affect favorability for occur- mineral resource appraisals. The general advancements in the mineral industry; rence of mineral deposits in an area or objective of this program is to assess the hence, they are not meant to be final judg- region. They may be diagnostic, permis- mineral resource potential of the lower 48 ments on areal or regional mineral poten- sive, or negative. states, using geology, geochemistry, tials. Diagnostic criteria are characteristics geophysics, remote sensing, statistics, present in all, or most, known deposits and computer science. The USGS has or- APPRAISAL METHODOLOGY that are commonly ganized the considered to be program and directs the work, The methodology used in these ap- necessary for the occurrence of but seeks the cooperation mineral and contribu- praisals was developed at a resource ap- deposits. The known absence of such tions of state geological surveys and in- praisal workshop convened by the USGS criteria may either severely limit or dividuals knowledgeable in the various in 1979 (Shawe, 1981). As part of that definitively rule out the disciplines and areas of possibility of study. workshop, scientists from government, deposits. Although diagnostic criteria in- Criteria considered important in the industry, and academia designed a dicate that selection of CUSMAP deposits may be present, they quadrangles are methodology for appraising the resource do not guarantee it. known or suspected mineral resource potential of 2° several quadrangles, one Permissive potential, percentage criteria are so commonly of federal land of which was representative of the mid- associated with deposits within the quadrangle, land changes that they are that continent geologic province. This evalua- considered to favor their presence. may affect future mineral resource Their tion procedure comprises six basic steps development, existence greatly enhances the possibility and need for improved (Pratt, 1981): of mineral deposits, especially if diagnos-

97 Kansas ^-, Missouri \ Illinois £ the Bonne terre, Davis, and Derby- i Doerun formations. • Some decomposed bedrock zones at the 1 i / base of residual ore occurrences are i 1 K f barite rich and soft enough to mine with ' conventional equipment. r~ k ir^ Structural controls JOPLIN SPRINGFIELD ROLLA PADUCAH^i • Principal controls are highlypermeable

1 zones related to fractures and voids in bedrock and algal reef structures. i

l • The main producing areas are bounded HARRISON j Kentucky;^ I— by a majorfault-block system. Faulting in the block has probably increased i

i i j host-rock permeability for penetration 1 of ore-forming fluids. Oklahoma ', Arkansas C Tennessee Geochemical indicators

Figure 1 Index map. •Barite occurrences in insoluble residues of carbonate rocks from drill tic criteria are present Absence of per- crushed stone quarry, and the mineral holes; barite in panned concentrates of missive criteria, however, does not neces- operation with the largest annual value of stream sediments. sarily reduce the possibility of mineral output is a lime plant. Geophysical indicators deposits so long as diagnostic criteria • Positive gravity anomalies in very occur. RESOURCE EVALUATION detailed surveys. Negative criteria generally can be Development of descriptive model Preparation of the equated with the known absence of diag- resource appraisal The first step in evaluating a resource nostic criteria. The descriptive model was used with commodity is to develop a descriptive the following criteria to prepare the model. An example is the following RECENT CUSMAP STUDIES resource appraisal: model, slightly modified from Pratt and CUSMAP studies have traditionally Diagnostic criteria Wharton (1981); this example, developed concentrated the identification on of 1. Outcrop areas of Potosi by Pratt and Wharton from available Dolomite and areas or regions favorable for metallic lower part of Eminence Dolomite; descriptive data, represents the known mineral deposits, but during several outcrop areas of Bonneterre, Davis, facts or features of barite deposits in the recent studies in Missouri this approach and Rolla Quadrangle. Lower Ordovician formations are began to change. less important. The study of the Rolla Quadrangle The typical ore body: barite by 2. Proximity to major and minor faults in the Missouri Geological Survey and the • Size: a few acres to more than 1500 a major fault block. USGS that began in 1977 was completed acres; thickness up to 50feet, averaging 3. Anomalous barium (100 ppm) in in- in May, 1981; this study was followed by about 10 feet. soluble residues of uppermost 300 ft the • a study of Springfield Quadrangle, Mode of occurrence: barite fragments, of drill holes. completed in 1985, and by studies of the mostly 1/2 inch to 6 inches long con- Permissive criteria Harrison and Joplin Quadrangles, still in tained in clayey^cherty residuum. 1. Barite deposit or occurrence at sur- progress. In October, 1986, preliminary • Tonnage: n x l(r tons of ore. face. planning began on assessment of the • Minimum grade: 75 to 100 lbs barite 2. Reported barite occurrence in drill- Paducah Quadrangle. Locations of these per y

98 prospected, so large undiscovered

deposits are unlikely; however, there is high potential for the discovery of small additional deposits in the area. Potential Resource Area 2 contains reported but unverified occurrences of barite in the Potosi-Eminence outcrop area and high barium in insoluble residues of several drill holes (diagnostic criteria 1 and 3). The barite occurrences lie between the Black fault to the northeast and the Ellington fault to the southwest; these faults may define a structural

block in the sense of diagnostic criteria 2. The extent of minor faulting in this area is unknown. Any existing major residual barite deposits would probably have been penetrated by some of the many holes drilled for water supply or base metal exploration or simply observed in outcrops, so there is little potential for the discovery Anomalous barite of additional large deposits. • in insoluable residue; Major barite mining I J area from uppermost 300 ft of drillhole Potential Resource Areas 3 and 4 con- W Barite mine; isolated Potential barite resource area tain insoluble residues with high barium | ( content in several A Barite occurrence; reported drill holes in the Potosi- [KrC~d potosi and Eminence Dolomite (but unverified) Eminence outcrop area. These areas pos- A Barite occurrence in drillhole; reported Igneous rock and Lamotte sess potentially favorable structure but Sandstone have been intensely explored by drilling. Major faults in Paleozoic rocks Bonneterre, Davis, Derby, Doerun, Gasconade Roubidoux, and Only small deposits are likely to be found Jefferson City Fms here. \//\ A|1 other formations The remainder of the Figure Barite resources Potosi-Emi- 2 (adapted from Pratt and Wharton, 1981). nence outcrop area and the remainder of the outcrop areas of the Bonneterre, The following brief description of the 1. Known resources of high-purity lime- Davis, and Lower Ordovician formations appraisal of one mineral commodity, stone. (High-purity theoretically limestones are for- have some potential for crushed stone, illustrates the approach mations that contain residual a significant barite deposits. used in the Springfield Quadrangle. section of limestone with a minimum The crushed stone resources of SPRINGFIELD the CaC03 content of 95 percent.) This QUADRANGLE: Springfield 2° Quadrangle are limestone criterion is met in two limestones. CRUSHED STONE POTENTIAL and dolomite; sandstone is considered an 2. Known Following resources of high-specification completion of the Rolla industrial sand resource. Some rock units aggregate. (High-specification Quadrangle study, ag- work began on the are suitable for all types of construction gregate is an arbitrary Springfield Quadrangle, category to immediately aggregate, others for aglime, and many designate stone that meets west of the Rolla Quadrangle. standard The for chemical and industrial use; some specifications established by the Mis- mineral resources of the Springfield resources have little or no economic souri Highway and Transportation Quadrangle differ greatly from those in value. Department and other agencies for the Rolla Quadrangle. All active ag- mineral For the appraisal, the nine mapped gregate used in portland cement con- production is from industrial minerals; geologic units were grouped into use crete.) Stone there has been no resources meeting this metal production since categories based on the known or poten- criterion occur in 1950. For this reason two limestones. industrial minerals tial suitability of the unit for various com- 3. Known resources of commercial were included in the evaluation lime- from the mercial uses. The use category for each stone and dolomite. (Commercial beginning of the study. The following in- unit was determined by present or past limestone and dolomite is a category dustrial minerals were considered worthy performance records of material from that of evaluation: includes rock units in the high- barite, clay and shale, that unit, laboratory tests, and similarity purity limestone crushed stone, dimension and high-specifica- stone, in- to other rock units with a history of use tion aggregate categories dustrial sand, and construction sand and those and either within the quadrangle or elsewhere suitable for less stringent aggregate gravel. Of these, only crushed stone and in southwest Missouri. Six use cate- and aglime construction use.) Stone resources in sand and gravel are of cur- gories were developed for stone resour- this category are rent economic importance. Lime, present in seven for- a ces in the quadrangle (modified from product mations. manufactured from crushed Rueff, 1985): 4. Known resources of high-purity limestone, was not considered separately. dolomite. (Resources in this category

99 dustrial minerals. Kentucky, Illinois, In- diana, and Missouri have recently begun a CUSMAP appraisal of the Paducah 1° x 2° Quadrangle, and an excellent opportunity exists to develop an appraisal system to meet the needs of the mineral industry, the government planner and regulator, and the general public. REFERENCES Martin, J. A., and Pratt, W. P. [eds.], 1985, Geology and mineral resource potential of the Springfield 1° x 2° Quad- rangle, Missouri as appraised in September, 1985: Missouri Depart- ment of Natural Resources, Division of Geology and Land Survey, Open- File Report OFR-85-42-MR. Pratt, W. P., 1981, Introduction, in Metal- lic mineral-resource potential of the \//\ Known resources of high-purity limestone and high-specification aggregate Rolla 1° x 2° Quadrangle, Missouri, as

of \ Known resources commercial limestone and dolomite appraised in September, 1980: U.S. Geological Survey Open-File Report !j Known resources of high-purity dolomite and hypothetical resources of high-specification 1 81-518, p. 3-9. ' aggregate Pratt, W. P., and Wharton, H. M., 1981, Areas of little or no commercial potential Barite deposits in residuum derived from vein and replacement deposits in • Sample sites Paleozoic rocks, in Metallic mineral- Figure 3 Crushed stone resources (adapted from Rueff, 1985). resource potential of the Rolla 1° x 2° Quadrangle, Missouri as appraised in are dolomite formations that contain a This map and the other industrial mineral September, 1980: U.S. Geological

section of stone with a combined maps are at a scale of 1:500,000 rather Survey Open-File Report 81-518, p.

CaC03 and MgC03 content of at least than the 1 : 250,000 scale used in the Rolla 23-25. 95 percent and at least 40 percent Quadrangle; they are intended only as Rueff, A. W., 1985, Industrial Minerals MgC03.) This criterion is met in two guides because detailed geologic open- Resources of the Springfield 1° x 2° formations. file maps at a scale of 1:62,500 are avail- Quadrangle, in Geology and mineral- 5. Speculative resources of high-speci- able. Tables providing average chemical resource potential of the Springfield fication aggregate. (This category and physical data for each unit having 1° x 2° Quadrangle, Missouri as ap- consists of stone resources that may commercial potential also were prepared. praised in September, 1985: Missouri contain a section of stone meeting the Detailed chemical and physical test data Department of Natural Resources, specifications of high-specification also are available as open-file reports. Division of Geology and Land Sur- aggregate, as defined earlier.) Only Graphs were prepared to show past stone vey, Open-File Report of R-OFR-85- one formation is in this category. production and current stone use. 42-MR, p. 27-33. 6. Areas and/or units with little or no com- Shawe, D.R., compiler, 1981, U.S. mercial potential. Large areas of the FUTURE APPRAISALS Geological Survey Workshop on non- Springfield Quadrangle are underlain The purpose of this report is not to dis- fuel mineral-resource appraisal of by formations having little or no com- cuss what has been done on the preceding wilderness and CUSMAP areas: U.S. mercial value as crushed stone ag- CUSMAPs but to stimulate discussion Geological Survey Circular 845. gregate. Five mapped rock units and about what can and should be done for fu- Wharton, H.M., 1987, Design capabili- areas near several major structural feature industrial mineral appraisals. Al- ties of lead mines, mills, smelters and tures are included in this category. though the methodology used in the iron pellet plants in southeast Missouri previous studies has worked well for in 1985-1986: Missouri Department The crushed stone resource map (fig. metallic minerals, it does not, for ex- of Natural Resources, Division of Ge- 3) is derived from the geologic map and ample, address cultural factors and other ology and Land Survey, handout, 1 from the earlier defined use categories. p. factors that so greatly affect many in-

100 Silica Sands: Grassroots Exploration or Acquisitions

Mark J. Zdunczyk Geoscience Corporation 12 Metro Park Road Albany, New York 12110

Marietta had purchased previously from ABSTRACT Wedron. Unimin built a plant near Kasota, Minnesota, and reconstructed In the a United States, companies interested in silica sands have done little Whitehead Brothers (now WHIBCO) grassroots exploration (that is, discovering a silica sand deposit by geologic plant in southern New Jersey. methods Unimin and then developing it). Simple reconnaissance of known sites is com- recently purchased Minnesota Frac Sand mon, but actual development of a deposit is rare. Most of the silica sand sites, Company from J.L. Shiely Company near whether consolidated or unconsolidated, are known. When these sites are redis- Jordan, Minnesota, Mid Continent Glass covered, as they often are, individuals wishing to capitalize on their discoveries Sand Company at Roff, Oklahoma, solicit and financial backing from large companies. However, although these redis- the International Minerals and Chemicals covered deposits may at first attract considerable interest, they seldom get (IMC) operation at Spruce developed. Pine North Carolina; the latter operation is silica-re- In recent years the silica sand industry in the United States has consolidated lated but also produces other industrial to afew major companies, andfurther consolidation is expected. Only three new minerals from the deposit. The plants have one been built in the past 6 years. Many factors associated with this in- Wedron plant not sold to dustry Unimin by Mar- prompt companies to acquire ongoing operations rather than explore for tin Marietta was at Wedron, Illinois; this new deposits. plant was purchased by Best Silica Com- This paper includes an examination of markets, industry trends, processing, pany (owned by Fairmount and product Minerals, specifications, and a briefdiscussion ofsome ofthefactors thatfavor Limited) and some of the remaining acquisitions over grassroots exploration. Wedron personnel. The most recent and largest acquisition was U.S. Borax's purchase of Penn- INTRODUCTION panies have taken significant steps to ac- sylvania Glass Sand Company, an ITT In recent years the silica sand (in- quire silica sand plants. In the late 1970s, subsidiary, and subsequent acquisition of dustrial sand) industry has experienced some established silica sand producers Ottawa Silica Company's six plants. 01- some major changes, especially con- began acquiring other such companies. gebay-Norton purchased a plant near solidation of operations by acquisitions. The Jesse S. Morie Company of New Jer- Riverside, California, from Owens-Il- In 1978 approximately 31 companies in sey (now the Morie Company) bought the linois and lands near Marston, North the United States were operating about 59 Georgia Silica operation from the Geor- Carolina, to continue its activity in this plants that provided most of the silica gia Marble Company and subsequently business. During this time only three new sand needed by industry consumers. acquired the Hardy Sand Company's plants were built. Vulcan built a plant Today approximately 10 major com- plants in West Tennessee and Alabama. near Brady, Texas, for the production of panies operate about 55 plants. The most Unisil Corporation had already begun to frac sand, Unimin built near Kasota, Min- recent U.S. Bureau of Mines survey buy small operations and eventually be- nesota, to produce frac or proppant sand, (1987) lists 94 companies that control came Unimin Corporation (financed by and J.L. Shiely Company built near Jor- 166 active operations. However, ap- Shibelco, Belguim). dan, Minnesota, to produce frac or prop- proximately six companies are closed, In the early 1980s, Martin Marietta's pant sand. Another new plant is currently the industrial sand-producing status of 36 purchase of the Wedron Silica Division of producing glass sand and other sands for companies is questionable, one company Del Monte properties increased its hold- specialty uses near Corona, California. no longer exists, one is sand and gravel ings from 6 to 1 1 plants. British Industrial only, and one is listed twice. The remain- Sand bought two plants from Manley PRODUCT SPECIFICATIONS ing companies have consolidated with the Brothers and reportedly planned to ac- The rigid specifications placed on majors or produce only one or two in- quire additional plants. Unimin Corpora- silica sand products such as glass sand, dustrial sand products such as blasting, tion, probably the most aggressive silica foundry sand, blast sand, and filter sand traction, or molding sands. Although the sand company in the United States, dictate the products a company can pro- acquisition of companies is not new for bought Carolina Silica near Marston, duce from a deposit. Generally, the most this industry, in recent years a few com- North Carolina, and plants that Martin stringent requirements regarding grain

101 size, chemistry, and heavy minerals con- sand), the market was already saturated. ity material at a fixed price for a number tent apply to glass sand. Grain sizes for In addition, major silica sand markets (for of years, are considered. melting sands require that less than 1 container glass) are being adversely af- weight percent be retained on a 30-mesh fected by strong competition from PROCESSING AND PLANT COSTS sieve. The amount retained on the 40- aluminum cans and plastic bottles, as well Beneficiation is usually the key to mesh sieve is usually held to 8 to 10 as the cardboard drink boxes recently in- making a high-quality glass or foundry weight percent and that passing a 140- troduced to the market. The use of these sand. To remove clay coatings from the mesh sieve to less than 5 weight percent. nonglass containers is expected to grow sand grains, the sand is pumped to a The Si02 content must exceed 99.5 per- in the next several years, possibly further primary desliming processor in which cent. The AI2O3 content should be less reducing the demand for glass containers. hydrocyclones remove the -0.01 -mm par- than 0.30 percent and the iron content, ex- Cullet (recycled glass) is also utilized ticles. The slimes are pumped to settling pressed as Fe203, should not exceed 0.30 in the container glass manufacturing ponds. After primary desliming, the clean weight percent. Limits are also placed on process, generally replacing 1 5 percent of sand is sized, either by hydrosizing in set- the amount of heavy refractory minerals the raw material mix. The cullet used in a tling tanks or on screens or possibly a (commonly found in young, uncon- container plant is obtained both from in- combination of both to remove the coar- solidated quartzose sand deposits) melt- house sources and from outside recy- ser fraction, usually the +0.5-mm par- ing sands can contain. Furthermore, cling. The bottle bills of the Northeast ticles (about 30-mesh size). Some plants heavy refractory minerals are likely to requiring use of returnable bottles have also use air classifiers to size dry sands. come under even more stringent created a large supply of cullet. Major The sand is dewatered by hydrocyclones specifications by the container industry beer and soda distributors have set up to 70 percent solids for attrition scrub- (KephartandDeNapoli, 1981). recycling plants to separate and clean cul- bing. Scrubbing is done in a compartment Foundry sand users may require a let for shipment, usually by rail, to glass- (sump) with propeller- type scrubbers. four-screen distribution, free from cal- container plants. Cullet is an important This process loosens and disperses any cium carbonate and other impurities. Fil- ingredient of the manufacturing process remaining coatings of iron oxides, clay, ter sand users demand a strict uniformity because it takes less energy to melt cullet and other materials affecting the sand coefficient and effective size specifica- than the same weight of raw sand. This grain surfaces; it also prepares fresh sur- tions, and even blast and traction sand recycling trend will continue to expand faces on the nonquartz minerals (heavy users impose certain specifications. and reduce consumption of silica sand. minerals) for reagent attachment in the Grain shape and screen size requirements The volume of float glass (window next step, which is flotation. Sometimes generally limit the products and deter- and plate glass) produced generally sodium hydroxide is used in the attrition mine the processing requirements and the varies with the economy, since this glass scrubbing process to help clean the grain markets for deposits exploited for prop- is used in the automotive and construc- surfaces. pant sands. Favorable geology, selective tion industries. Because new cars are Flotation, if necessary, is the next step mining, quality processing, and creative smaller and require less glass and because in processing the sand. Two types of flota- marketing are required for a company to the thickness of windshields and lights is tion, cationic and anionic, are used. successfully meet the many specifica- decreasing, not much increase in glass- Anionic flotation is probably the more tions for these markets. sand demand is expected in the automo- common; this process uses a petroleum tive industry. Recent increases in sulphonate collector in an acid circuit to MARKETS AND TRENDS residential and commercial construction remove the heavy minerals. To a large extent, markets dictate a will boost float glass consumption. The sand must be dried for most uses, company's decision to acquire or to ex- Some increase in silica sand (in- and this is normally done in rotary or plore and build. For example, the supply dustrial sand) sales may come from fluidized-bed dryers with wet scrubbers of silica sand for midwestern consumers products such as roofing sand, blasting for dust removal on the exhaust system. has always been plentiful. Long-estab- sand, filter sand, and other specialty sand Many glass sand producers use the fluid- lished companies produce from the St. products. These areas demand new ized-bed-type dryers because of their Peter and Jordan Sandstones, Michigan processing and marketing skills. One high reliability and thermal efficiency. dune sand, the Sylvania Formation, and major new market for silica sand consists After drying, the sand may be conveyed the Sharon Conglomerate. Price wars are of high-purity products requiring unique to another set of screens for final size con- common, especially in the Illinois-In- processing for relatively small tonnages trol. Foundry sands generally have to be diana area. The odds are against a for piezoelectric and glass crystal cooled before shipment; therefore, a newcomer's building a successful plant products. cooling cycle must be introduced to the in this area. For example, the J.L. Shiely Any company has difficulty breaking sand processing operation. Company built Minnesota Frac Sand into the market as a new supplier of silica The type of processing just described Company to produce frac sand, but failed; sand. The customer may at first insist on is generally more elaborate, and therefore Unimin subsequently bought the plant using a new supplier's product on a trial more costly, than that required to produce and is reported to be working from the basis and later, if the product meets ap- construction-grade sand and gravel. A stockpiles only. Unimin also closed its proval, as a second source. No longer will plant built to produce 500,000 tons of plant at Kasota, Minnesota. Although the consumers buy all their silica sand from high-quality glass or foundry sand per oil industry slump did not help these two one plant unless special contracts, year may require more than 10 million plants (which produced mostly proppant providing for a continual supply of qual- dollars in engineering and construction

102 —

costs. A new plant being built near local, state, and federal environmental not be able to be as cost-competitive as Corona, California, with a capacity to regulations concerning water and air long-established produce competitors. 600,000 tons per year reportedly quality control and mined land restora- • In general, the deposits least costly to will cost $16 million, whereas a plant tion. According to Peddicord and Regis mine, process, and designed distribute, are al- to produce comparable ton- (1981), the most important and costly of ready being exploited. If an apparently nages of sand and gravel for construction the permits required, the Conditional Use excellent deposit isn't being used, there aggregate may cost $3 to million $5 dol- Permit Requirements, typically include: are probably good reasons why: it may lars to build. be too expensive • zoning and integration with a local to mine or process, it The following list (adapted from Shuf- master-planning and development may be too distant from markets, or flebarger, 1983) includes processing scheme transportation facilities may be poor. steps that may be used in producing high- • restrictions on operating times Extensive testing quality glass sand. The exact mix of to assure product • implementation of detailed water-well quality is often required processes is a function of the deposit, before new raw monitoring programs materials can products, and markets. enter a market • noise and seismic survey of blasting on 1. drying and screening only (rare) and off the property CONCLUSION 2. washing (generally the removal of • monitoring and mitigation of fugitive I have discussed briefly some factors clay), drying, and screening dust that persuade company officials to ac- 3. washing, scrubbing, flotation, drying, • complete reclamation plans quire existing operations rather than ex- and screening • detailed site plan plore, purchase land, and build new silica 4. washing, scrubbing (high pulp density plants. It is not uncommon today for a silica Officials of most major companies attrition), drying, screening, and prefer sand mining company to be permitted to to purchase a producing facility, sizing by air separation possibly mine only 50 percent of its property (Ped- change some processing equip- 5. iron removal (magnetic, wet, or dry) ment, dicord and Regis, 1981). obtain new permits, and have es- 6. grinding (rod mill, ball mill), regard- tablished Health and safety constraints have customers waiting for their less of process used, if indicated by been placed on silica plants, especially products rather than to struggle to over- natural grain-size distribution come those manufacturing silica flour, by the the many obstacles (including high 7. acid leach for high-purity products Mine Safety and Health Administration costs) associated with grassroots explora- 8. bagging facilities for some or all (MSHA) and the Occupational Safety tion and development. products and Health Administration (OSHA). A 9. cooling facilities for foundry sand bagging facility for silica sand products REFERENCES Kephart,W.W.,andF.H.DeNapoli,1981, TRANSPORTATION installed at one operation cost $3 million to meet the health and Glass container industry specifica- The safety require- availability of good truck and rail tions ments of the various regulatory groups. for raw materials in the 1980s, in routes near a potential silica sand site is Proceedings, Minerals and chemicals essential for profitable operation. Al- SILICA INDUSTRY PROSPECTS in glass and ceramics the next though — silica sand, unlike sand and decade, Although most of the potential silica Corning, NY, p.74. gravel, may be shipped great distances to sand sites have been located and inves- Peddicord, R.C., and A.J. Regis, 1981, a customer, it is not always possible to The tigated at one time or another, "new" sites effect of environmental, reg- have a distribution center close to the are still available as they are redis- ulatory, technological, and marketing market and still be competitive: high covered. Operators of some small com- constraints on the cost of producing labor and equipment costs are required to glass panies near the markets who believe that sands, in Proceedings, Minerals place a large number of trucks or railcars their deposits contain quality materials and chemicals in glass and ceramics at the disposal of the glass customers or the often fail to understand why they cannot next decade, Corning, NY, p. 86- users to ensure that the carriers can be obtain financial backing; the following 88. loaded as required to meet the delivery factors may help explain their difficulty: Shufflebarger, Thomas E., Jr., 1983, schedule (Peddicord and Regis, 1981). Glass sand prospects and exploration, • The size of the Truck delivery is usually more market for industrial depend- SME Preprint 83-100, AIME Annual sand is decreasing, able and more costly than rail delivery. not growing. Meeting, Atlanta, GA, p. 2. • A new company must take customers U.S. Department of the Interior, Bureau ENVIRONMENTAL away from existing companies in a FACTORS of Mines, Mineral saturated market. Industry Surveys, The silica sand industry, like most Directory of Industrial • The high Sand and Gra- other mining industries, initial capital cost of opening must obtain vel Producers a new mine and in the U.S., 1987, p. 1. various types of permits to comply with processing plant probably means that a newcomer will

103

Z "

Enhancement of Sulfur Dioxide Sorption Reactivity of Limestone

M. Rostam-Abadi, q q Sresty D. L. Moran, R R. Frost, and R. D. Harvey Chemistry and Chemical Engineering Research Div ' Illinois State Geological Survey Illinois Institute of Technology Research Institute Champaign, Illinois 61820 Chicago, Illinois 60616

ABSTRACT

S rbem injection for co" tr° 1 of sulfur dioxJde emissions from the combustion of high-sulfur coal is nn.^w ,h , an emerging tech- a pulvenz d ! calcium-based sorbent is injected directly ? ' ** into the furnace cavity of a^ £boiler.w™The sorbentr?T SSSl (limestone or hydrated lime, for instance) decomposes to lime, which reacts with the sulfur dTox de to VvoZt hydratCd UmCS m°re reaCUVe ^^ *" " ^ Carb°nateS beC3USe *™£S£ S^^The objective of this work to was compare the surface areas and reactivities of products prepared by three hydration methods In the firs method lime was hydrated with alcohol-water solutions. In the second method, hydrated limes were Tat hfeh pressure, 120 to 475 atmospheres and subsequently ejected to atmospheric conditions. In the S Ld method ZTw£heated whh detemmed by BET *• teChniqUC> and Sulfur di0xide sorPtion reacdvide w obtaSy 5SJ™^ ^ * ^ ^ S a° e S di Xide W SOrpd0n caPacities of *e hydrated limes depended on sorbent a nH ^ Tf fu f ^ type, calcination conditions hydl n 0r 3 PamCUlar IimeSt°ne> Steam h ydration imProved caJcium utilization (conversion of calcium oxide£?H?^.?to calcium sulfate)r ?K°by c/percent 84 over the lime from which it was prepared. Surface 2 areas between 34 and 49 m /g ami cT ciumuuhzauons between 50 and percent 93 were observed for times hydrated with water at 2 atmospheric pressure tesu^- hydrated limes had lower surface areas to (10 20 m /g) and utilizations (70% to 100%). A linear relationship wa i obse^edKSi reactivity and surface area for these hydrates. Results from this study showed the following order of reactivity- Ethanol-water hydration = methanol-water hydration pressure * hydration steam hydration = with water lime.

" ' ** ^^^ ^^^ S°** °ivision f Fud B"*** v 32 no 4 Au 30 ^^ ° " ' " ' 8«« 1987. 508- SO. NeT^ka^LA ^ - p.

Reserve Evaluation and Planning on an IBM Personal Computer

George F. Swindle Mentor Consultants, Inc. P.O. Box 3147 Glen Ellyn, Illinois 60137 ABSTRACT An IBM desktop personal computer and a proprietary software package (PC/Cores) were used for evaluating the 3 Quantities and ^ ** ** The *"** pr°jeCt is described from borehole cap Ivetnrnen iSTh^ ' ^J 1 LSd^Se n r ^ " muldPle seam Pining. A unique methS^f^n ^ ! quaSJ SnTtoconstraints to Ithe modestmodel and to the Tdisplay^TJ'of histogram'^T™' and quality-array tables is also described * ge°l0giStS mlning 6ngineerS Can USe U themselves corr^uTr^ognlmmen ' *" ^ without havi"g * 'onsult a

105