DOCSLIB.ORG

Efflorescent Iron Sulfate Minerals: Paragenesis, Relative Stability, and Environmental Impact

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Efflorescent Iron Sulfate Minerals: Paragenesis, Relative Stability, and Environmental Impact American Mineralogist, Volume 88, pages 1919–1932, 2003 Efflorescent iron sulfate minerals: Paragenesis, relative stability, and environmental impact JEANETTE K. JERZ* AND J. DONALD RIMSTIDT Department of Geological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, U.S.A. ABSTRACT This study of a pyrrhotite-dominated massive sulfide deposit in the Blue Ridge province in south- western Virginia shows that sulfate minerals formed by the oxidation of the pyrrhotite transform from one to another by a combination of oxidation, dehydration, and neutralization reactions. Significant quantities of sulfate minerals occur in the underground adits (Area I) and under overhangs along the high sidewall of the adjoining open pit (Area II). Samples from this site were analyzed to determine mineralogy, equilibrium relative humidity, chemical composition, and acid generation potential. In Area I, pyrrhotite oxidizes to marcasite + melanterite, which eventually oxidizes to melanterite + sul- furic acid. Melanterite is extruded from the rocks as a result of the volume change associated with this reaction. It accumulates in piles where halotrichite, copiapite, and fibroferrite form. In Area II, FeSO4 solutions produced by pyrrhotite oxidation migrate to the exposed pit face, where they evaporate to form melanterite. The melanterite rapidly dehydrates to form rozenite, which falls into a pile at the base of the wall, where melanterite, copiapite, and halotrichite are present. The observed paragenesis a a can be understood using a log O2 – log H2O diagram that we developed from published thermody- namic data and observations of coexisting phases. Dissolution experiments showed that fibroferrite-rich samples had the highest acid producing po- tential, followed by copiapite-rich samples and then halotrichite-rich samples. The most abundant metals in solutions produced by dissolving impure bulk samples of the salts were Mg, Al, Zn, Cu, Ca, and Pb. The molar concentrations of the metals varied with mineralogy. However, all of the sulfate minerals release metals and acid when they dissolve and therefore represent a potentially significant environmental risk. INTRODUCTION Fe S93- x O5- x H O()1 x Fe(OH) + H SO (2) 1- x ++4 2 2 2324 =- Acid mine drainage (AMD) environments provide of a rich tapestry of mineralogy and geochemistry. Although the het- Iron sulfide and iron oxyhydroxide geochemistries have erogeneity and complexity of AMD systems can make them been well studied (see Nordstrom and Alpers 1999 and refer- difficult to study, we expect them to show a systematic pattern ences therein), but the equally important iron sulfate phases of mineral paragenesis. Knowledge of this paragenesis is im- are less well understood. The objective of this study is to es- portant for quantifying the environmental impact of the miner- tablish the geochemical relationships of some important iron als, predicting the evolution of AMD sites, and identifying sulfate minerals that occur in AMD environments. effective AMD remediation methods. A first step toward ad- Numerous hydrated iron sulfate minerals are known (Table dressing the paragenesis problem is to consider only reactions 1), and their mineralogy and geochemistry are discussed in a involving the most important AMD elements: iron, sulfur, oxy- recent review by Jambor et al. (2000). Efflorescent iron sulfate gen, and hydrogen. The important acid mine drainage minerals minerals are common in base metal deposits, coal deposits, and can be divided into three types: iron sulfides, iron sulfates, and tailings and waste rock piles where they are frequently associ- iron oxyhydroxides. The overall AMD-forming process in- ated with oxidizing iron sulfide minerals. Because of their high volves a complex chain of reactions that link the oxidation of solubility, most iron sulfate minerals only persist under rock iron sulfides to the precipitation of iron oxyhydroxides and the overhangs and similar sheltered sites where they are protected release of sulfuric acid to receiving waters. For pyrite and mar- from dissolution during rain events. The minerals can also form casite, the overall reaction is: in the open during drier times as sulfate-rich solutions migrate to the surface and evaporate. 15 7 These iron sulfate minerals form when solutions rich in iron FeS2 +4 O2 +2 H2324 O = Fe(OH) + 2H SO (1) sulfate and in sulfuric acid evaporate in surficial environments. and for pyrrhotite the overall reaction is: The evolution from ferrous sulfate minerals to iron oxyhydroxide minerals occurs by a series of oxidation, dehy- dration, and neutralization reactions. The mineralogy that de- * Present address: Department of Geology and Geography, velops at any particular site will be controlled by the relative DePauw University, 602 South College Avenue, Greencastle, rates of each of these types of reactions. We can predict the Indiana 46135, U.S.A. E-mail: [email protected] order in which the minerals in Table 1 are likely to form by 0003-004X/03/1112–1919$05.00 1919 1920 JERZ AND RIMSTIDT: EFFLORESCENT IRON SULFATE MINERALS examining their stoichiometries in terms of these three reac- are related by oxidation, neutralization, and dehydration reac- tion types. The axes of Figure 1, based on the atomic ratios of tions. The oxidation axis expresses the amount of cationic chemical constituents, are designed to show how the minerals charge provided by ferric iron divided by the total cationic charge. This number increases when ferrous iron oxidizes to TABLE 1. Minerals that occur in the system Fe-S-O-H ferric iron. The neutralization axis expresses the ratio of an- Name and abbreviation Formula ionic charge provided by hydroxide to the total charge pro- 3+ hematite hem Fe2 O3 vided by all anions. This number increases as minerals goethite goe Fe3+OOH 3+ incorporate hydroxide from solution or as sulfate is lost to so- hydrous ferric oxide* hfo Fe (OH)3·nH2O 3+ maghemite† mhem Fe2 O3 lution as H2SO4. The dehydration axis expresses the number of 3+ quenstedtite quen Fe2 (SO4)3·10H2O moles of water molecules per total moles of cationic charge. 3+ coquimbite coq Fe2 (SO4)3·9H2O 3+ This ratio decreases as water is lost by dehydration. The bold paracoquimbite‡ pcoq Fe2 (SO4)3·9H2O 3+ kornelite korn Fe2 (SO4)3·7H2O arrow shows the general trend of compositions as ferrous sul- 3+ lausenite laus Fe2 (SO4)3·6H2O fates evolve to iron oxyhydroxides. The diagram explains why 3+ hohmannite hoh Fe2 (SO4)2(OH)2·7H2O 3+ minerals such as lausenite (lau) are rare in AMD environments; metahohmannite mhoh Fe2 (SO4)2(OH)2·3H2O 3+ fibroferrite fib Fe (SO4)(OH)·5H2O they can form only under strongly acidic conditions. More com- 3+ amarantite amar Fe (SO4)(OH)·3H2O 3+ mon minerals, such as copiapite (cop), fall near the most direct butlerite but Fe (SO4)(OH)·2H2O 3+ parabutlerite pbut Fe (SO4)(OH)·2H2O path leading from melanterite (mel) to goethite (goe). By ex- 2+ 3+ bilinite bil Fe Fe2 (SO4)4·22H2O amining the geochemistry, mineralogy, and occurrence of these 2+ 3+ römerite röm Fe Fe2 (SO4)4·14H2O 2+ 3+ phases, we can begin to map out the important reactions that copiapite cop Fe Fe4 (SO4)6(OH)2·20H2O 3+ ferricopiapite fcop Fe5 O(SO4)6OH·20H2O result in the overall transformation processes. 2+ melanterite mel Fe SO4·7H2O Knowledge of the sulfate mineralogy and paragenesis at an 2+ ferrohexahydrite fhex Fe SO4·6H2O 2+ AMD site is important because different sulfate minerals carry siderotil sid Fe SO4·5H2O 2+ rozenite roz Fe SO4·4H2O different amounts of trace elements and produce different 2+ szomolnokite szo Fe SO4·H2O 3+ amounts of acid upon dissolution. The dissolution of iron sul- rhomboclase rhom H3OFe (SO4)2·3H2O 3+ hydronium jarosite h-jar H3OFe3 (SO4)2(OH)6 fate minerals during rain events can dramatically affect aquatic 3+ schwertmannite sch Fe 16O16(OH)12(SO4)2 ecosystems. Dagenhart (1980) showed a clear relationship be- Note: Not all of these minerals are found in the AMD environment. The tween stream discharge and stream chemistry during rain events abbreviations are used in subsequent figures and tables in this paper. * A complex group of phases that includes ferrihydrite and lepidocrocite. (Fig. 2). His data show that during the initial phase of a rain † Polymorph of hematite. ‡ Polymorph of coquimbite. 4.00 3.75 mel 3.50 fer 3.25 4 sid 3.00 roz 2000 bil 3 1500 röm 2 1000 szo que coq cop 500 kor fib 1 lau fcop amarhoh ff 600 but 0 mhoh 0 0 0.2 400 0.2 0.4 0.4 goe 0.6 0.6 200 0.8 hem0.8 1.0 0 0 25 50 75 100 Time (hrs) FIGURE 1. The stoichiometries of iron sulfate and iron oxide FIGURE 2. Hydrograph of Contrary Creek, Virginia, showing the minerals are directly related to the reactions that transform one phase relationship between stream discharge and stream chemistry for rain into another. Mineral stoichiometries and abbreviations are given in events in June, 1978 (Dagenhart 1980). The bold vertical lines represent Table 1. Changes in the ratios along the axes correspond to chemical rain events. Runoff from the first storm event dissolved sulfate minerals reactions that are responsible for iron sulfate mineral transformations and carried the resulting acidic, sulfate-rich solution to the stream, in acid mine drainage environments. These reactions are dehydration causing an increase in acidity and conductivity. After a short time, (z-axis), neutralization (y-axis), and oxidation (x-axis). The bold line relatively fresher water from upstream diluted the stream. Later storm shows a generalized paragenesis path involving these three reactions events produce smaller excursions in conductivity and pH because the that converts ferrous sulfate to iron oxyhydroxides. sulfate minerals had been previously washed away. JERZ AND RIMSTIDT: EFFLORESCENT IRON SULFATE MINERALS 1921 event, there was a marked decrease in pH and an increase in This paper builds on the results of these previous studies of dissolved solids as iron sulfate minerals dissolved and the acid the paragenesis of sulfate minerals and their environmental im- sulfate solutions were carried by overland flow into the stream.
Load more

Recommended publications
  • Download PDF About Minerals Sorted by Mineral Name
    MINERALS SORTED BY NAME Here is an alphabetical list of minerals discussed on this site. More information on and photographs of these minerals in Kentucky is available in the book “Rocks and Minerals of Kentucky” (Anderson, 1994). APATITE Crystal system: hexagonal. Fracture: conchoidal. Color: red, brown, white. Hardness: 5.0. Luster: opaque or semitransparent. Specific gravity: 3.1. Apatite, also called cellophane, occurs in peridotites in eastern and western Kentucky. A microcrystalline variety of collophane found in northern Woodford County is dark reddish brown, porous, and occurs in phosphatic beds, lenses, and nodules in the Tanglewood Member of the Lexington Limestone. Some fossils in the Tanglewood Member are coated with phosphate. Beds are generally very thin, but occasionally several feet thick. The Woodford County phosphate beds were mined during the early 1900s near Wallace, Ky. BARITE Crystal system: orthorhombic. Cleavage: often in groups of platy or tabular crystals. Color: usually white, but may be light shades of blue, brown, yellow, or red. Hardness: 3.0 to 3.5. Streak: white. Luster: vitreous to pearly. Specific gravity: 4.5. Tenacity: brittle. Uses: in heavy muds in oil-well drilling, to increase brilliance in the glass-making industry, as filler for paper, cosmetics, textiles, linoleum, rubber goods, paints. Barite generally occurs in a white massive variety (often appearing earthy when weathered), although some clear to bluish, bladed barite crystals have been observed in several vein deposits in central Kentucky, and commonly occurs as a solid solution series with celestite where barium and strontium can substitute for each other. Various nodular zones have been observed in Silurian–Devonian rocks in east-central Kentucky.
    [Show full text]
  • Acquisition and Evaluation of Thermodynamic Data for Morenosite-Retgersite Equilibria at 0.1 Mpa
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln USGS Staff -- Published Research US Geological Survey 2003 Acquisition and Evaluation of Thermodynamic Data for Morenosite-Retgersite Equilibria at 0.1 MPa I-Ming Chou 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A., [email protected] Robert R. Seal II 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A. Follow this and additional works at: https://digitalcommons.unl.edu/usgsstaffpub Part of the Earth Sciences Commons Chou, I-Ming and Seal II, Robert R., "Acquisition and Evaluation of Thermodynamic Data for Morenosite- Retgersite Equilibria at 0.1 MPa" (2003). USGS Staff -- Published Research. 328. https://digitalcommons.unl.edu/usgsstaffpub/328 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in USGS Staff -- Published Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. American Mineralogist, Volume 88, pages 1943–1948, 2003 Acquisition and evaluation of thermodynamic data for morenosite-retgersite equilibria at 0.1 MPa I-MING CHOU* AND ROBERT R. SEAL II 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A. ABSTRACT Metal-sulfate salts in mine drainage environments commonly occur as solid solutions containing Fe, Cu, Mg, Zn, Al, Mn, Ni, Co, Cd, and other elements. Thermodynamic data for some of the end- member salts containing Fe, Cu, Zn, and Mg have been collected and evaluated previously, and the present study extends to the system containing Ni.
    [Show full text]
  • Raman Spectroscopy of Efflorescent
    ASTROBIOLOGY Volume 13, Number 3, 2013 ª Mary Ann Liebert, Inc. DOI: 10.1089/ast.2012.0908 Raman Spectroscopy of Efflorescent Sulfate Salts from Iron Mountain Mine Superfund Site, California Pablo Sobron1 and Charles N. Alpers2 Abstract The Iron Mountain Mine Superfund Site near Redding, California, is a massive sulfide ore deposit that was mined for iron, silver, gold, copper, zinc, and pyrite intermittently for nearly 100 years. As a result, both water and air reached the sulfide deposits deep within the mountain, producing acid mine drainage consisting of sulfuric acid and heavy metals from the ore. Particularly, the drainage water from the Richmond Mine at Iron Mountain is among the most acidic waters naturally found on Earth. The mineralogy at Iron Mountain can serve as a proxy for understanding sulfate formation on Mars. Selected sulfate efflorescent salts from Iron Mountain, formed from extremely acidic waters via drainage from sulfide mining, have been characterized by means of Raman spectroscopy. Gypsum, ferricopiapite, copiapite, melanterite, coquimbite, and voltaite are found within the samples. This work has implications for Mars mineralogical and geochemical investigations as well as for terrestrial environmental investigations related to acid mine drainage contamination. Key Words: Acid mine drainage—Efflorescent sulfate minerals—Mars analogue—Iron Mountain—Laser Raman spectroscopy. Astro- biology 13, 270–278. 1. Introduction efflorescent sulfate minerals. This reconnaissance sampling resulted in characterization of the extremely acidic mine ron Mountain, California, is the host of massive sulfide waters (pH values from - 3.6 to + 0.5) and a variety of iron- Ideposits that were mined for copper, zinc, gold, silver, and sulfate efflorescent salts (Nordstrom and Alpers, 1999; pyrite (for sulfuric acid) between the early 1860s and the early Nordstrom et al., 2000).
    [Show full text]
  • Barite (Barium)
    Barite (Barium) Chapter D of Critical Mineral Resources of the United States—Economic and Environmental Geology and Prospects for Future Supply Professional Paper 1802–D U.S. Department of the Interior U.S. Geological Survey Periodic Table of Elements 1A 8A 1 2 hydrogen helium 1.008 2A 3A 4A 5A 6A 7A 4.003 3 4 5 6 7 8 9 10 lithium beryllium boron carbon nitrogen oxygen fluorine neon 6.94 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 13 14 15 16 17 18 sodium magnesium aluminum silicon phosphorus sulfur chlorine argon 22.99 24.31 3B 4B 5B 6B 7B 8B 11B 12B 26.98 28.09 30.97 32.06 35.45 39.95 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.64 74.92 78.96 79.90 83.79 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 85.47 87.62 88.91 91.22 92.91 95.96 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 cesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 132.9 137.3 178.5 180.9 183.9 186.2 190.2 192.2 195.1 197.0 200.5 204.4 207.2 209.0 (209) (210)(222) 87 88 104 105 106 107 108 109 110 111 112 113 114 115 116
    [Show full text]
  • Mineralogy of the Martian Surface
    EA42CH14-Ehlmann ARI 30 April 2014 7:21 Mineralogy of the Martian Surface Bethany L. Ehlmann1,2 and Christopher S. Edwards1 1Division of Geological & Planetary Sciences, California Institute of Technology, Pasadena, California 91125; email: [email protected], [email protected] 2Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 Annu. Rev. Earth Planet. Sci. 2014. 42:291–315 Keywords First published online as a Review in Advance on Mars, composition, mineralogy, infrared spectroscopy, igneous processes, February 21, 2014 aqueous alteration The Annual Review of Earth and Planetary Sciences is online at earth.annualreviews.org Abstract This article’s doi: The past fifteen years of orbital infrared spectroscopy and in situ exploration 10.1146/annurev-earth-060313-055024 have led to a new understanding of the composition and history of Mars. Copyright c 2014 by Annual Reviews. Globally, Mars has a basaltic upper crust with regionally variable quanti- by California Institute of Technology on 06/09/14. For personal use only. All rights reserved ties of plagioclase, pyroxene, and olivine associated with distinctive terrains. Enrichments in olivine (>20%) are found around the largest basins and Annu. Rev. Earth Planet. Sci. 2014.42:291-315. Downloaded from www.annualreviews.org within late Noachian–early Hesperian lavas. Alkali volcanics are also locally present, pointing to regional differences in igneous processes. Many ma- terials from ancient Mars bear the mineralogic fingerprints of interaction with water. Clay minerals, found in exposures of Noachian crust across the globe, preserve widespread evidence for early weathering, hydrothermal, and diagenetic aqueous environments. Noachian and Hesperian sediments include paleolake deposits with clays, carbonates, sulfates, and chlorides that are more localized in extent.
    [Show full text]
  • Acquisition and Evaluation of Thermodynamic Data for Morenosite-Retgersite Equilibria at 0.1 Mpa
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by UNL | Libraries University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln USGS Staff -- Published Research US Geological Survey 2003 Acquisition and Evaluation of Thermodynamic Data for Morenosite-Retgersite Equilibria at 0.1 MPa I-Ming Chou 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A., [email protected] Robert R. Seal II 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A. Follow this and additional works at: https://digitalcommons.unl.edu/usgsstaffpub Part of the Earth Sciences Commons Chou, I-Ming and Seal II, Robert R., "Acquisition and Evaluation of Thermodynamic Data for Morenosite- Retgersite Equilibria at 0.1 MPa" (2003). USGS Staff -- Published Research. 328. https://digitalcommons.unl.edu/usgsstaffpub/328 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in USGS Staff -- Published Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. American Mineralogist, Volume 88, pages 1943–1948, 2003 Acquisition and evaluation of thermodynamic data for morenosite-retgersite equilibria at 0.1 MPa I-MING CHOU* AND ROBERT R. SEAL II 954 National Center, U.S. Geological Survey, Reston, Virginia 20192, U.S.A. ABSTRACT Metal-sulfate salts in mine drainage environments commonly occur as solid solutions containing Fe, Cu, Mg, Zn, Al, Mn, Ni, Co, Cd, and other elements. Thermodynamic data for some of the end- member salts containing Fe, Cu, Zn, and Mg have been collected and evaluated previously, and the present study extends to the system containing Ni.
    [Show full text]
  • I Identification and Characterization of Martian Acid-Sulfate Hydrothermal
    Identification and Characterization of Martian Acid-Sulfate Hydrothermal Alteration: An Investigation of Instrumentation Techniques and Geochemical Processes Through Laboratory Experiments and Terrestrial Analog Studies by Sarah Rose Black B.A., State University of New York at Buffalo, 2004 M.S., State University of New York at Buffalo, 2006 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirement for the degree of Doctor of Philosophy Department of Geological Sciences 2018 i This thesis entitled: Identification and Characterization of Martian Acid-Sulfate Hydrothermal Alteration: An Investigation of Instrumentation Techniques and Geochemical Processes Through Laboratory Experiments and Terrestrial Analog Studies written by Sarah Rose Black has been approved for the Department of Geological Sciences ______________________________________ Dr. Brian M. Hynek ______________________________________ Dr. Alexis Templeton ______________________________________ Dr. Stephen Mojzsis ______________________________________ Dr. Thomas McCollom ______________________________________ Dr. Raina Gough Date: _________________________ The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. ii Black, Sarah Rose (Ph.D., Geological Sciences) Identification and Characterization of Martian Acid-Sulfate Hydrothermal Alteration: An Investigation
    [Show full text]
  • Azu Td Hy E9791 1968 43 Sip
    A study of crystallization from water of compounds in the system Fe² - Cu² - So₄². Item Type Thesis-Reproduction (electronic); text Authors Walton, Wayne J. A. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 24/09/2021 05:15:43 Link to Item http://hdl.handle.net/10150/191508 A STUDY OF CRYSTALLIZATION FROM WATER OF COMPOUNDS IN THE SYSTEM Fe -CU++ - SO4= by Wayne J. A. Walton, Jr. A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOLOGY In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1968 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfill- ment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknow- ledginent of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author.
    [Show full text]
  • Jerzdissertation.Pdf (5.247Mb)
    Geochemical Reactions in Unsaturated Mine Wastes Jeanette K. Jerz Dissertation submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Geological Sciences Committee in charge: J. Donald Rimstidt, Chair James R. Craig W. Lee Daniels Patricia Dove D. Kirk Nordstrom April 22, 2002 Blacksburg, Virginia Keywords: Acid Mine Drainage, Pyrite, Oxidation Rate, Efflorescent Sulfate Salt, Paragenesis, Copyright 2002, Jeanette K. Jerz GEOCHEMICAL REACTIONS IN UNSATURATED MINE WASTES JEANETTE K. JERZ ABSTRACT Although mining is essential to life in our modern society, it generates huge amounts of waste that can lead to acid mine drainage (AMD). Most of these mine wastes occur as large piles that are open to the atmosphere so that air and water vapor can circulate through them. This study addresses the reactions and transformations of the minerals that occur in humid air in the pore spaces in the waste piles. The rate of pyrite oxidation in moist air was determined by measuring over time the change in pressure between a sealed chamber containing pyrite plus oxygen and a control. The experiments carried out at 25˚C, 96.8% fixed relative humidity, and oxygen partial pressures of 0.21, 0.61, and 1.00 showed that the rate of oxygen consumption is a function of oxygen partial pressure and time. The rates of oxygen consumption fit the expression dn −− O2 = 10 648...Pt 05 05. dt O2 It appears that the rate slows with time because a thin layer of ferrous sulfate + sulfuric acid solution grows on pyrite and retards oxygen transport to the pyrite surface.
    [Show full text]
  • Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy)
    Georgia State University ScholarWorks @ Georgia State University Geosciences Theses Department of Geosciences 4-27-2010 Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy) Jennifer M. Dickie Georgia State University Follow this and additional works at: https://scholarworks.gsu.edu/geosciences_theses Part of the Geography Commons, and the Geology Commons Recommended Citation Dickie, Jennifer M., "Mineralogical and Geochemical Indicators of Subaerial Weathering in the Pozzolane Rosse Ignimbrite (Alban Hills Volcanic District, Italy)." Thesis, Georgia State University, 2010. https://scholarworks.gsu.edu/geosciences_theses/23 This Thesis is brought to you for free and open access by the Department of Geosciences at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Geosciences Theses by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. MINERALOGICAL AND GEOCHEMICAL INDICATORS OF SUBAERIAL WEATHERING IN THE POZZOLANE ROSSE IGNIMBRITE (ALBAN HILLS VOLCANIC DISTRICT, ITALY) by JENNIFER M. DICKIE Under the direction of Dr. Daniel Deocampo ABSTRACT The Pozzolane Rosse ignimbrite [PR] (457±4 ka) in the Alban Hills Volcanic District, Rome, Italy was exposed ~ 40 ka prior to a subsequent volcanic event which coverd it entirely. XRF, XRD, and clay separation results from PR samples from INGV and CA1 boreholes and Castel di Leva quarry show evidence of paleopedogenesis. All locations display loss of base cations, loss of K is consistent with XRD datat showing dissolution or alteration of leucite to analcime. Accumulation of Al and high L.O.I. support XRD evidence of 1:1 clay species at upper depth.
    [Show full text]
  • Alunogen Al2(SO4)3 • 17H2O C 2001-2005 Mineral Data Publishing, Version 1
    Alunogen Al2(SO4)3 • 17H2O c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Triclinic. Point Group: 1. Crystals rare, as thin plates or prismatic [001] or {010} with a six-sided outline about [010], very complex, with about 60 forms noted. Commonly fibrous, to 5 mm, forming delicate masses, crusts, and efflorescences. Twinning: On {010}. Physical Properties: Cleavage: {010}, perfect; probable on {100} and {313}. Hardness = 1.5–2 D(meas.) = 1.72–1.77 D(calc.) = 1.79 Soluble in H2O; taste alumlike, acid and sharp. Optical Properties: Transparent. Color: Colorless in crystals, aggregates white, or pale yellow or red from impurities; colorless in transmitted light. Luster: Vitreous to silky. Optical Class: Biaxial (+). Orientation: X ' b; Z ∧ c =42◦. α = 1.459–1.475 β = 1.461–1.478 γ = 1.470–1.485 2V(meas.) = 31◦ Cell Data: Space Group: P 1. a = 7.420(6) b = 26.97(2) c = 6.062(5) α =89◦57(5)0 β =97◦34(5)0 γ =91◦53(5)0 Z=2 X-ray Powder Pattern: Nov´aBaˇna, Slovakia. 4.489 (100), 4.390 (81), 3.969 (81), 4.329 (76), 13.46 (54), 3.897 (52), 3.675 (45) Chemistry: (1) (2) SO3 37.74 37.04 Al2O3 16.59 15.73 H2O 44.64 47.23 insol. 0.94 Total 99.91 100.00 • (1) Pintado Canyon, Guadalupe Co., New Mexico, USA. (2) Al2(SO4)3 17H2O. Occurrence: Forms by reaction of sulfates from decomposing sulfides with aluminous minerals in shales and slates; in gossan or altered wall rock of pyritic deposits in arid regions; in coal seams; in relatively low-temperature fumaroles.
    [Show full text]
  • High Temperature Sulfate Minerals Forming on the Burning Coal Dumps from Upper Silesia, Poland
    minerals Article High Temperature Sulfate Minerals Forming on the Burning Coal Dumps from Upper Silesia, Poland Jan Parafiniuk * and Rafał Siuda Faculty of Geology, University of Warsaw, Zwirki˙ i Wigury 93, 02-089 Warszawa, Poland; [email protected] * Correspondence: j.parafi[email protected] Abstract: The subject of this work is the assemblage of anhydrous sulfate minerals formed on burning coal-heaps. Three burning heaps located in the Upper Silesian coal basin in Czerwionka-Leszczyny, Radlin and Rydułtowy near Rybnik were selected for the research. The occurrence of godovikovite, millosevichite, steklite and an unnamed MgSO4, sometimes accompanied by subordinate admixtures of mikasaite, sabieite, efremovite, langbeinite and aphthitalite has been recorded from these locations. Occasionally they form monomineral aggregates, but usually occur as mixtures practically impossible to separate. The minerals form microcrystalline masses with a characteristic vesicular structure resembling a solidified foam or pumice. The sulfates crystallize from hot fire gases, similar to high temperature volcanic exhalations. The gases transport volatile components from the center of the fire but their chemical compositions are not yet known. Their cooling in the near-surface part of the heap results in condensation from the vapors as viscous liquid mass, from which the investigated minerals then crystallize. Their crystallization temperatures can be estimated from direct measurements of the temperatures of sulfate accumulation in the burning dumps and studies of their thermal ◦ decomposition. Millosevichite and steklite crystallize in the temperature range of 510–650 C, MgSO4 Citation: Parafiniuk, J.; Siuda, R. forms at 510–600 ◦C and godovikovite in the slightly lower range of 280–450 (546) ◦C.
    [Show full text]