Winter 1995 L I T E NewMexico Bureau ~.~, .~,..,.~ "~ ~,,~..~,~.~.,..~,~ of ...... ¯ Mines and .’..:. .i .,.."".. . Resources (NMBM&MR)

A quarterly publication for educators arid the public- contemporary geological topics~ issues and events EadhBriefs ", Bombs, and Ground Water Peter S. Mozley Departmentof Earth and EnVironmental Science, NewMexico Tech Concretions are hard masses of sedimentary and, more rarely, volcanic that form by the preferential precipitation of () in localized portions of the rock. They are commonlysubspherical, but frequently form a variety of other shapes, including disks, grape-like aggregates, and complex shapes that defy description (Figs. 1, 2, and 3). Concretions are usually very noticeable features, because they have a strikingly. different color and/or hardness than the rest of the rock. In someareas this is unfortunate, as the concretions have attracted the unwanted attention of local graffiti artists. Commonly, when you break open concretions you will find that they have formed around a nucleus, such as a fragment or piece of organic matter. For a variety of reasons, this nucleus created a more favorable site for precipitation than other sites in therock. ~erhapsthe mostunusual "[ spent too much time in thesame place in the back swamp .nucleiarefound in a modemcoastal’ and the clanged concretion went and nucleated on me." saltmarsh in England. (FeCOa) concretionsin the marshformed aroundWorld-War-II era military shells,bombs, and associated shrapnel, ThisIssue: includingsome large unexploded shells(AI-Agha et al.,1995). A British Earth Briefs--how does Nature conceal Reptiles’onthe Rocks--someunique geologiststudying these concretions bombs and record ancient water-flow photosof homedlizards in New realizedthis only after striking a large pathways? Mexico unexplodedshell repeatedly with his rockhammer (yes, he livedto tellabout Have you ever wondered... Howhas our Trips and worksl~ops for Earth science it)!The concretions formed climate varied in the past? teachers (see page 10 and 12) preferentiallyaround the military debrisbecause it providedan abundant sourceof ironfor the siderite. In ,concr&ions often preserve

New Mexico Bureau of Mines and Mineral Resources 1 Lite Geology,Winter 1995 Figure 2--Complexelongete concretions in the Zia Formation (Miocene), NM.I.ens cap for scale.

Figure l~"Cannonball" concretions in the Zia Formatum (Miocene), NM. Photo courtesy of Dave I ,ove.

Figure 3--1 luge elongate concretions in the Zia Formation (Miocene), NM. Figure 4---~,ptarian concretion from the Mancos , NM.Top concretior~ has been cut on a rock saw to reveal septarian fractures filled with several generations of coarsely crystalline calcite cement. Top concretion is 10 cm in diameter. Concretions courtesy of NMBM&MR Mineral Muset,m.

Winter 19q5, I.ite Geolo£,tt 2 New Mexico Bureau of Mines and Mineral Resources features of the original --such (Raiswell, 1971; Astin, 1986). Mexico’s most important aquifer as burrows, , and sedimentary Alternatively, some authors have (Mozley and Davis, 1996). Elongate layering--that cannot be seen in the rest suggested that they originate as tensile concretions have even been found in of the rock. Preservation of primary fractures produced in response to faults cutting the Santa Fe Group, where features occurs because concretions burial and compaction (Astin, 1986). they record the past flow orientation of usually form relatively early, before The name septarian originates from the ground water in the fault zone (Mozley sediment compaction and other Latin word saeptum (enclosure or wall), and Goodwin, 1995). processes disrupt the original sediment. referring to the raised cracks on the Thus, cementation of the concretions outside of some septarian concretions. Acknowledgements "freezes" the early sediment structure, If you are interested in hunting for Thanksto Stuart Burley for relating his hair raising encounter with’the Linconshire forming a rigid mass that resists later septarian concretions in New Mexico, Washconcretions. This article benefitted alterations. Examining the concretions many are found in the Mancos Shale, a from the commentsand suggestions of Virgil is the only way of understanding these marine unit found in Lueth. early features. northwest New Mexico. Septarian concretions are the most Recently hydrologists have become References commontype of concretion found in interested in elongate concretions. AI-Agha,M. R., Burley, S. D., Curtis, C. D., rock and mineral shops. In these These concretions range in size from and Esson, J., 1995, Complexcementation concretions the fine-grained concretion pencil- and cigar-like bodies to those textures and authigenic mineral body (usually composed of calcite, that resemble large fallen logs (Figs. assemblages in Recent concretions from CaCO~)is cut by a radiating network of and 3). They are thought to form from the Linconshire Wash(east coast, UK) fractures filled with coarsely crystalline flowing ground water, with the long driven by Fe(0) Fe(lI) oxidation: Journal of the Geological Society, London,v. 152, calcite and other minerals (Figs. 4 and axis of the concretion oriented parallel pp. 157-171. 5). The origin of the fractures is poorly to the ground-water flow direction understood, but they may result from (McBride et al., 1994). In formations Astin, T. R., 1986, Septarian crack formation internal shrinkage of the concretion where such concretions are common, in concretions from shales and mudstones: Minerals, v. 21, pp’. 617- body (like the cracks found in seasoned measuring concretion orientation can L 632. firewood). This shrinkage may be provide a direct measurement of the related to dehydration or past ground-water flow orientation over McBride, E. E, Picard, M. D., and Folk, R. transformation of a gel-like mineral a large area. Such concretions are L., 1994, Oriented concretions, Ionian Coast, Italy--Evidence of precursor in the concretion interior common in the Santa Fe Group, New flow direction: Journal of Sedimentary Research, v. A64, pp. 535-540. Mozley,P. S., and Davis, J. M., 1996, Relationship between oriented calcite concretions and permeability correlation structure in an alluvial aquifer, Sierra Ladrones Formation, New Mexico: Journal of Sedimentary Research, v. 66, pp. 11-16. Mozley, P. S., and Goodwin,L., )995, Patterns of cementation along a Cenozoic normal fault: A record of paleoflow orientations: Geology,v. 23, pp. 539-542. Raiswell, R., 1971, The growth of Cambrian and Liassic concretions: Sedimentology,v. 17, pp. 147-171.

Figure 5--, Moeraki Formation, , South lslanct, NewZealand. These huge septarian calcite concretions were exposed when the shale host rock was eroded by wave action. Photo courtesy of James Boles.

New Mexico Bureau of Mines and Mineral Resources 3 Life Geology, Winter 1995 Have you ever wondered...

... Howour climate has research is leading and point out some weather-shaping, upper-level winds examples pertinent to NewMexico. called jet streams to alter their course varied in thepast? (Fig. 2). The effects are often droughts Part 1: The El Nifio effect Oceans and atmospheric currents in Australia, India, and Africa; floods in First-order effects on climate are the South Americaand California; and col,d, CharlesE. Chapin circuJation patterns in the oceans and wet winters in NewMexico. For ’ Director and State Geologist, NMBM&MR atmosphere. The two are strongly example, the Albuquerque Journal on interrelated as has been graphically De~:ember17, 1992 (an El Nifio year) Manyof us have listened .to illustrated by the El Niflo effects in reported that Novemberwas the grandparents and elderly neighbors recent years. The El Nifio or ENSO(El coldest in Albuquerque since 1938 tell of how when they were young Nifio--southern Oscillation) is (average,temperature 39.7 °F versus the climate was different. Small warmingof surface waters in the eastern normal average of 44 °F) and the streams were bigger then and had Pacific near the Equator(Fig. I). It snowiest since 1946 (5.9 inches versus more fish in them, or winters were caused by a weakening of the trade 0.38 inches). Of(icial snowfall more severe, etc. Such stories are winds that normally blow westward Albuquerque up to December 17th was usually received with polite across the equatorial south Pacific. As 19.6 inches, making1992 the fifth interest and considerable they weaken, warmPacific surface snowiest year of the past 100 years. skepticism. But howvariable is our waters that usuallybuild up near Asia Whata contrast with 1995! climate.., and how can we fiod begin flowing eastward.t0ward Central The El Nii’lo-Southern Oscillation is out? and South America (Fig. 1A) bringing actually a cycle with both warmand Widely publicized worries about unusually warmcurrents to the region. cold extremes. The warm extreme (El the buildup of carbon dioxide in Whythe trade winds weaken is not Nifio) is driven by an eastward the Earth’s atmospl~ere, as a result known. propagating, broad wave of of burning fossil fuels, and the The build up of warmsurface waters, downwelling warm surface water that possibility of global warming, with thousands of miles across, in the eastern depresses the therm0cline (the thin the melting of ice caps and rise of Pacific causes the globe-circling, layer of steep temperature gradient sea level, etc., have elevated research on past climates to serious business. Climate change is now a NorthAmerica major field of interdisciplinary research and a voluminous 1982El Ni~o literature has developed around the subject. In fact, there is so much"" research being done, on such a A wide variety of subjects, by such a diverse groupof scientists, that it is reminiscent of the excitement and controversies during the plate tectonics revolution of the 1960s and 70s. Determination of past climates (beyond historical records) generally requires two things: 1) material, landform, or event whose age can be accurately measured, B and 2),a characteristic or ]:n’operty of a material that can be reliably related to a climate variable, such as temperature or precipitation. A IllusZrationby Becky Titus wide variety of opportunities exist Modifiedfrom an original illqstration by SzevenDavis, Earth, to gain insight into past climates, both local and global. Beginning Figdre t--Map of the equatorial Pacific showing sea surface temperatures (A) ¯ with this article, I will attempt to during the 1982 El Nifio event (when slackening of the westward-blowingtrade summarize where some of this winds allowed warm surface waters to "slosh" eastward toward Central and South America) and one year later (B) during the westwardreturn flow (La Nifia). Modified from Knox, 1992. Winter1995, Lite Geology 4 New Mexico Bureau of Mines and,Mineral Resources i

separating warm surface watersand Ni~o can be said to be und.erway when of the Lima Geographical Society, drew cold deeper waters) and inhibits the sea level at the GalapagosIslands in attention to the El Ni~ocurrent in a normal upwelling of cold deep waters the eastern Pacific is 2 centimeters (0.8 short paper in the bulletin of the ¯ along the west coast of South America. inches) above its normal height for six Society. Andin 1895, Sei~or Federico The disappearance of the cold, nutrient- or more consecutive months. As you Pezet of the Lima Geographical Society" laden watersaround Christmas time can see, these waves of warmor cQld described the El Ni~lo current and its and its negative impact on fisheries led water are very broad and of low effects ir~ ah address to the Sixth fishermen to call the phenomenon"El amplitude, requiring sensitive International Geographical Congress. NiPto," after the Christ child. Duringthe measurementsto detect them. It was The appearance of the warm counter- other half of the cycle, the rejuvenated the advent of satellites carrying very current coincided with heavy rains in trade winds blow the warm surface. sophisticated instruments during the arid regions where it seldom rains. waters westward away from South last 20 or 30 years that allowed America so that they again accumulate scientists to gain an understanding of Prediction and measurement of El in the western Pacific. The cold half of the El Ni~o-Southern Oscillation Niflo the cycle was called La Nit~a by the effect. Early in this century, British fishermen, meaning "the girl". But The roots of El Ni~o research, meteorologist Sir Gilbert Walker, the somescientists prefer the term El Viejo, however, date back muchearlier. The Director-General ol~ Observatories in meaning "old man." coast of Peru is normally bathed by India, began studying tropical climate Howare El Ni~o-Southern cold waters of the Humboldtcurrent fluctuations after the 1899 disastrous Oscillation events defined and that flows northward toward the failure of the monsoonrains in India. measured? The Japanese Equator. Peruvian sailors whonavigate The El Ni~to years of 1877 and 1888 also Meteorological Agencyconsiders an El these waters in small boats noticed saw widespread famine in India and Nitro (the warmextreme) to long ago that a warmcounter-current, heavy loss of life.’Walker’s goal was to underway when sea surface flowir/g from north to south appeared predict variations in the northward flow temperature in the tropical Pacific immediately after Christmas some of moisture-laden air from the Indian Ocean is a minimumof 0.5°C (0.9°F) years. It was actually this current that Ocean that provides the summer warmerthan normal for at least six was named El Nitro by the fishermen. monsoonrains so necessary to India’s consecutive months. Alternatively, an El In 1891, Dr. Louis Carranza, President Continued on page 8 ~"

D~c~a~n/JA.uARY Polar Jet Stream shlTted well north of normal; , warmin eastern North America

+ Strong low-pressure J.ANUARY ’ area; record Amplified storm track rains and tloodlng

polar Jet Stream J

,,J ANUAR,Y Normal Pacific Powerful Jet .~tream Jet Stream well south of normal directs i~i~ major storms and moisture into California ) ",,

Figure 2--Map showing typical effects of an El Ni~o on winter weather patterns in the United States. The northern and eastern states enjoy unusually warm, dry weather because a displaced polar jet stream keeps cold Arctic air from reaching as far south as it normallydoes during winter. In the west, the Pacific jet stream is south ’of its usual route, driving El Ni~o-fed storms directly into Californih. The El Niflo effect enhances Pacific storminess but other, unrelated weather patterns also help determine the paths of the jet streamS. Drawing modified from National Oceanic and Atmospheric Administration/Climate Prediction Center data, (Monastersky, 1995).

New Mexico Bureau of Mines and Mineral.Resources 5 Lite Geology,. Winter1995 Reptiles on the Rocks

Here are some horned lizards t~f NewMexico photographed in various geologic settings. Descriptions of the horned lizards are by Gary Stolz, National Interpretive Specialist, U.S. Fish and Wildlife Service. Photos are by Dave Love, NMBM&MR Senior Environmental Geologist.

Photo AmShort-hornedlizard Phrynosomadouglassl The short-horned lizard is the widest ranging of seven species of these curious reptiles native to the United States. Found from southwestern to northern Mexico, short-horns are more cold-tolerant than other species. Short-horned lizards have adapted by giving birth to live young to help survive cooler temperatures and limited incubation seasons found within latitudes and altitudes of their homerange (all other U.S. species lay eggs). Throughoutthe diverse range of native habitats, horned lizards depend on camouflage to escape predation. Over generations, natural selection gives a survival advantage to those that blend best with their surroundings. Here we see an individual from the MagdalenaMountains with coloration matching rocks and lichens on which it dwells, while the disruptive coloration of the dorsal stripe helps break up a recognizable body line.

Winter 1995, Life Geology 6 New Mexico Bureau of Mines and Mineral Resources Photo B--Short-horned lizard Phrynosoma douglaul The short-horned lizard, like the individual shownhere, can grow to four inches. It can be recognized by relatively short horns on its head with a U-shapedseparation in the center, a single row of fringe scales on its sides, and light dorsal mid-line stripe. Note the different coloration of this specimen, blending well with its habitat of Cretaceous of Sand Canyon,east of El Malpais. Short-horns, like other horned lizards, spend muchof their time hidden just below the ground surface where they find protection from predators and extremes in temperature.

New Mexico Bureau of Mines and Mineral Resources 7 Lite Geology,Winter 1995 agriculture. (NewMexico is also ,highs and "lows" at mid-latitudes Maine with waves up to 30 feet high. dependent on northward flow of moist maycause storms to divert from their The summerof 1993 saw relentless air for most of its summerrainfall.) normal paths and lead to unusual rains inundate the Midwest/forcing Walker noticed that the barometric weather conditions in some locations. thousands from their homes and pressures recorded by land-based That the world’s oceans should have flooding 23 million acres of farmland. stations between 1905 and 1937 on the such major influence on the atmosphere The following winter saw a record eastern and western sides of the Pacific and weather patterns is notsurprising blizzard with hurricane force winds Ocean tended to seesaw back and forth. when you consider the high capacity of that churned up the eastern seaboard, He called this periodic variation of water to store heat (a property of water killing 270 people. Meanwhile, atmospheric pressure the Southern utilized in manysolar heated homes in , Australia was suffering a major Oscillation and linked it to many NewMexico). The upper three meters drought. On the plus side, scientists climatic variables around the world. (9 f.eet) of ocean water hold as much. have found that there are noticeably Unfortunately, he was not able to use it heat as the entire atmosphere! fewer Atlantic hurricanes during El to accurately predict monsoonfailures; Nifio years. other factors apparently are involved. Effects Of El Ni/Io Since the El Nifio of 1991-94 ended, E! Nittos usually occur every three to New Mexico has experienced two Water Temperatures seven years and last one to two years, unusually warm and dry winters, a Tl~e large body of warmwater that but the latest El Nii~o was a double record-breaking summerheat wave in straddles the Equator northeast of cycle that lasted from January 1991 to 1994, a partial failure of our summer Australia (Fig. 1B) is called the Western mid-1994(Fig. 3), and somesay it monsoonal rains, and major problems Pacific WarmPool (WPWP),which lasted until mid-1995. Weather around for ranchers and the ski areas, which covers an area lal"ger than the the globe was unusually severe during brings us to the subject of weather continental United States. The WPWP this interval. For example, heavy rains prediction and its importance. "has a tempe’rature consistently higher through the winter’and spring of 1992 Understanding the El Nifio-southern than 28°C(82°F) about 2°C to 5°C (3.6 caused major flooding in Texas Oscillation and detecting the changes in 9°F) higher than that of other equatorial (rememberthe earlier description of its cycle early can help reduce the waters, and is the largest single what that winter was like in New economicdevastation and loss of life expanse of warmwater on Earth. Mexico). In December1992 that often accompanies extremes of Between El Nii~os, the westward "nor’easter" of hurricane velocity weather. A speaker at a geological blowing trade winds dragwarm ’ poundedthe east coast from Virginia to surface waters into the western Pacific raising sea level there as muchas 16 inches (40 cm) higher than sea levels -. near South America. Whenthe trade winds .weaken, the pool of warm water i begins to drift eastward, which starts another El Nifio. The position of the warmest water may vary from one oscillation to another and lead to different effects in separate El Ni~os, ® -10 m possibly chusing floods one time and droughts the next. -2o Warmsurface waters heat the overlying atmosphere, stimulating 1960 1970 .1980 1990 evaporation and pumping moisture and energy high into the atmosphere. El Nitro ~ La Nii~a (El Viejo) Whenthe moisture condenses into rain, ¯ it gives off heat, further warmingthe ’Figure 3--Graphshowing the SouthernOscillation from 1963to’ 1994. Thedark- atmosphere. This fountain of heat and shadedregions indicate ¯El Nil’to events; the light-shadedregions indicate La Ni~ut moisture provides a major engine for (El Viejo) events. Thesolid line indicates the sea level anomaliesin the Galapagos global atmospheric circulatiom A series Islands near the SouthAmerican coast. Notethat sealevel in the Galapagosis of low- and high-pressure cells radiate higher during El Nil’to eventsbecause of the arrival 6f a broadwave of warm from the air overlying the pool of. warm surface waters from the westernPacific. Modified from Meyersand O’Brien, Dec. 5, water. Variations in the pattern of these 1995issue of Eos, Transactionsof the AmericanGeophysical Union.¯

’Winter 1995, Lite Geology 8 New Mexico Bureau Of Mines and Mineral Resources meeting in Denver has even correlated variations in the price of natural gas Funfor kids... Free trip for a New with El Nifio events; he suggests that Falcon Magazine is for kids whoare Mexico teacher the El Nifio cycles can be useful in wild about wildlife: This bi-monthly strategic planning by both energy publication is filled with fun stories, June 19-22, 1996; Scottsdale, Arizona producers and large consumers. During pictures, and amazing facts about The 5th National Minerals Education El Nifio years, the populous wildlife, conservation, and the Conference is an opportunity for northeastern United States and environment. To order .Falcon teachers to gather information and southeastern Canada are unusually Magazine, call i-(800) 582-2665. resources to help teach mineral science. warmand dry. During El Viejo years, The Central NewMexico Section of the the southwestern United States is warm Funfor Earth science Society for Mining; Mineral, and and dry and the northeast gets its Exploration (SME)will send a New normal cold and snowywinter, as it has teachers Mexicoteacher to the conference With this year. April 19, 1996; Albuquerque To apply, call George NationalAssociation of GeologyTeachers Austin, SME,GEM Committee Chair, Further Reading will present Geology and Earth Science c/o New.Mexico Bureau of Mines (505) 835-5230;fax (505) 835--6333. Cane, M.A., 1986, Et Nifio: AnnualReview workshops for teachers at the New of Earth and PlanetarySciences, v. 14, pp. Mexico Museumof Natural History in Applications are due May1st, 1996. 43-70. Albuquerque. The emphasis is on fun, Canby,T. Y., 1984,El Nifios’ill wind: geology, samples, and curriculum NationalGeographic, v. 165, pp, 144-183. ideas. Staff from the Museum,N.M Knox,E N., 1992, Acurrent catastrophe: El Bureau of Mines,. UNMCollege of Nifio: Earth,v. 1, no. 5, pp. 30-37. Education and Department of Earth and Phinetary Sciences, and other agencies Monastersky,R., 1995, Tropical trouble: Two k. decades of Pacific warmthhave fired up will conduct sessions on a variety of the globe: ScienceNews, v. 147, pp. 154-- topics. For more information, please. 155. contaqt Chris Whittle, Southwest Indian PolytechnicInstitute (SIPI), at (505) 897-5380; or fax (505) 897-5713.

0. Life ~ology evolvm. Lite Geologybegan as a small Earth- science publication designed alad Lite Geology scaled for NewMexico. Our subscription list nowincludes a large ,*Please send me Lite GeologyD **($4.00 enclosed for out-of-state subscribers) numberof out-of-state readers. In order Name to keep up with the demandfor this publication from outside of New Mailing address Mexico, we will charge $4.00 per year City State Zip for out-of-state readers, whichcovers the cost of printing and mailing. The Howdid you hear about Lite Geology? subscription year begins with the Fall issue, and ends with the Summerissue Are you a teacher? to correspond with the academic year. At what school do you teach? If you reside outside Of NewMexico Grade level? and wish to keep your subscription active, please return this form with a Subject(s) check for $4.00. If you have questions, please call Theresa Lopez at (505) 835- *For in-state subscribers, please send in this form only once 5420. **Beginningwith the Fall 1994 issue, out-of-sta’t6 subscribers will k., t be charged $4.00 per year to cover printing and mailing costs.

New Mexico Bureau oFMines and Mineral Resources 9 Lite Geology,Winter 1995 Reptiles on the Rocks

Photo CmRoundtallhorned llzard Phrynosomamodestum Lookinglike just another basalt pebble, near a volcanic crater in the northern portion of Jornada del Muerto, this roundtail horned lizard is barely visible to predators or prey. As fascinating and beloved creatures, horned lizards have long captured humancuriosity and imagination. These harmless and beneficial reptiles have been celebrated by Native Americanson their pottery and rock art and by Hollywoodin movies. Today horned lizards are faced with threats to habitat destruction, over collection, and the introduction of exotic species such as fire ants. Hornedlizards have survived on the Earth for millions of years, yet like all wildlife species, they nowdepend on Our stewardship of a shared planet for their future.

Winter1995, l.ite Geolagy 10 New Mexico Bureau of Mines and Mineral Resources L I T E .gy

Teachertraining on is published quarterly by NewMexico Bureau of Mines and Mineral Resources is comingsoonl (Dr. Charles E. Chapin, Director and State Geologist), a division of NewMexico Tech eismic Sleuths: May6--8, 1996 (Dr. Daniel H. Lopez,President). The first in a series of four workshopsfor teachers Purpose:to build Earth science awareness on earthquakes will be held in Socorro at the New by presenting educators and the public Mexico Bureau of Mines and Mineral Resources with contemporarygeologic topics, issues, (NMBM&MR).Seismic Sleuths features hands-on and events. Use Life Geologyas a source activities to integrate math, science, and social studies for ideas in the classroomor for public concepts as applied to earthquakes. The curriculum was , education. Reproductionis encouraged developed for Federal Emergency Management Agency with proper recognitioo of the source. All (FEMA)by the American Geophysical Union (AGU). rights reservedon copyrighted© material MexicoSeismic Sleuths curriculum will contain a special reprintedwith permissionwithin this issue. volcanic hazards section developed by NMBM&MR.The Lite GeologyStaff Information workshopsare free, and travel and per diem are available if Editor: SusanJ. Welch participants travel more than 30 miles to attend. For more GeologicalEditors: Dr. DaveLove, Dr. information, or to register, call Bob Redden, NewMexico Charles Chapin, and Gretchen Departmentof Public Safety at (505) 827-9254; or call Susan "Hoffman Welch, NMBM&MR,at (505) 835-5112. Educational Coordinator:Barbara Popp Graphic Designer: Jan Thomas Ne~v Mexico/Princeton Earth Physics Project Cartoonist: Jan Thomaswith inspiration (NM/PEPP): July 8--12, 1996 from Dr. Peter Mozley Travel and per-diem funding are available for 20 New Editorial Assistant: TobyClick Mexicomiddle school, high school, and college science teachers to participate in Creative and TechnicalSupport: an NSF-funded.national program to develop and teach a series of curriculum NMBM&MRStaff modules focused on seismology. For a selected subset of workshopparticipants, Mailing Address NM/PEPPwill purchase and install in schools Internet-linked, high-quality NewMexico Bureau of Mines and Mineral seismographs to facilitate teaching and collaborative research projects with other Resourues, 801 Leroy Place, Socorro, NM membersof the academic community. For more information, contact Dr. Rick Aster, 87801. Phone (505) 835-5420. For Dept. of Earth and Environmental Sciences, NewMexico Tech, by phone at (505) subscription information, please call or -835-5924; e-mail at [email protected]; or call Susan Welch. write. Lite Geologyis printed on recycled paper.

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Winter1995, Lite Geology ~12 "New Mexico Bureau of Mines and Mineral Resources