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Reviews in Economic Volume 7

APPLICATIONS OF MICROANALYTICAL TECHNIQUES TO UNDERSTANDING MINERALIZING PROCESSES

CONTENTS PART I: AND RADIOGENIC ISOTOPES U-Th-Pb Geochronology by Ion Microprobe I.S. Williams ICP Multiple-Collector Mass Spectrometry A.N. Halliday, J.N. Christensen, D.-C. Lee, C.M. Hall, and In Situ High-Precision Isotopic Analysis C.J. Ballentine, M. Rehkamper, W. Yi, X. Luo, and D. Barfoo 40Ar/39Ar Geochronology Using the Laser Microprobe K .V. Hodges PART II: STABLE ISOTOPES Ion Microprobe Analysis of Oxygen, J.W. Valley, C.M. Graham, B. Harte, J.M. Eiler, and P.D. Kinny  Carbon, and Hydrogen Isotope Ratios Laser Microanalysis of Silicates for 18O/17O/16O and of D. Rumble and Z.D. Sharp Carbonates for 18O/16O and 13C/12C Ratios Sulfur Isotopes by Ion Microprobe M.A. McKibben and L.R. Riciputi Sulfur Isotope Analyses Using the Laser Microprobe W.C. Shanks, III, D.E. Crowe, and C. Johnson PART III: ELEMENTAL ANALYSIS Ion-Microprobe Quantification of Precious Metals in Sulfide Minerals A.C.L. Larocque and L.J. Cabri Micro-PIXE in Science J.L. Campbell and G.K. Czamanske Economic Applications of Accelerator Mass Spectrometry G.C. Wilson Major, Trace, and Ultratrace Element Analysis by Laser Ablation ICP-MS W.I. Ridley and F.E. Lichte PART IV: FLUID INCLUSIONS Evidence for Sources of Salinity and Dissolved Gases, Fluid Mixing and J.J. Irwin Phase Separation, from Laser Microprobe Analysis of Cl, K, Br, I Ar, Kr, and Xe in Fluid Inclusions The Laser Raman Microprobe as a Tool for the Economic Geologist J.D. Pasteris Synchrotron-Source X-ray Fluorescence Microprobe: D.A. Yanko and J.A. Mavrogenes Analysis of Fluid Inclusions

Editors M.A. McKibben, W.C. Shanks, III, and W.I. Ridley

SOCIETY OF ECONOMIC GEOLOGISTS, INC. Society of Economic Geologists, Inc.

Reviews in , Vol. 7 Applications of Microanalytical Techniques to Understanding Mineralizing Processes M.A. McKibben, W.C. Shanks, III, and W.I. Ridley, Editors

Additional copies of this publication can be obtained from

Society of Economic Geologists, Inc. 7811 Shaffer Parkway Littleton, CO 80127 www.segweb.org

ISBN: 978-1-629495-65-1 The Authors:

Louis J. Cabri Frederick E. Lichte W.C. Shanks, III CANMET U.S. U.S. Geological Survey 555 Booth Street Denver Federal Center Branch of Ottawa, Ontario KIA OGI Box 25046, Mail Stop 973 973 Denver Federal Center Canada Denver, CO 80225 Denver, CO 80225 Tel. +1.613.995.4073 USA USA Fax +1.613.996.9673 Tel.+ 1.605. 787.6837 Tel.+ 1.303.236.2497 email: [email protected] email: [email protected] Fax +1.303.236.3200 email: [email protected]. usgs.gov lain Campbell John A. Mavrogenes University of Guelph Research School of Earth Sciences Zachary D. Sharp U.C. 4th Floor The Australian National University Department of Earth and Guelph, Ontario NIG 2Wl Canberra, A.C.T. 0200 Planetary Sciences Canada Australia Northrop Hall Tel. +1.519.824.4120 ext. 3846 Tel. +011.61.249.3416 University of New Mexico Fax +1.519.767.1693 Fax +011.61.249.5989 Albuquerque, NM 87131 email: jlc@. uoguelph.ca email: [email protected] USA Tel.+ 1.505.277.2000 G.K. Czamanske Michael A. McKibben Fax +1.505.277.8843 750 W. Greenwich Place Department of Earth Sciences email: [email protected] University of California Palo Alto, CA 94303 USA Riverside, CA 92521 John W. Valley Tel. +1.650.328.7153 USA Department of Geology and email: [email protected]. usgs.gov Tel.+1.909.787.3444 University of Wisconsin-Madison Fax+1.909.787.4324 Madison, WI 53706 Alex N. Halliday email: [email protected] USA Department of Geological Sciences Tel. + 1.608.263.5659 University of Michigan Jill Dill Pasteris Fax +1.608.262.0693 2534, C.C. Little Building Department of Earth and email: [email protected] Ann Arbor, MI 48109-1063 Planetary Sciences USA Washington University David A. Yanko Tel+1.13.764.1482 1 Brookings Drive, Campus Box 1169 Department of Geology Fax +1.313.763.4690 St. Louis, MO 63130-4899 Georgia State University email: [email protected] USA P.O. Box 4105 Tel.+1.314.935.5434 Atlanta, GA 30302-4105 Kip Hodges Fax +1.314.935.7361 USA Massachusetts Institute of Technology email: [email protected] Tel. +1.404.651.2272 Cambridge, MA 02139 Fax +1.404.651.1376 USA W. Ian Ridley email: [email protected] Tel. + 1.617.253.2927 U.S. Geological Survey Fax + 1.617.253.6735 Denver Federal Center Ian S. Williams email: [email protected] Box 25046, MS 973 Geochronology and Denver, CO 80225 Research School of Earth Sciences J.J. Irwin USA The Australian National University Cadence Mineral Resources Inc. Tel. + 1.303.236.5558 Canberra, ACT 0200 2658 Bellevue Avenue Fax +1.303.236.3200 Australia West Vancouver, BC V7V 1E4 email: [email protected] Tel. +011.61.2.6249.5164 Canada Fax +011.61.2.6279.8345 Tel. + 1.604.644.6515 Lee Riciputi email: [email protected] Fax +1.604.683.2235 Oak Ridge National Lab email: [email protected] P.O. Box 2008 Graham C. Wilson Oak Ridge, TN 37831-6365 IsoTrace Laboratory Adrienne Larocque USA University of Toronto Department of Geological Sciences Tel. +1.423.576.4839 60 St. George Street University of Manitoba Fax +1.423.576.8559 Toronto, Ontario M5S IA7 125 Dysart Rd. email: [email protected] Canada Winnipeg, MB R3T 2N2 Tel. +1.416.466.3386 Canada Douglas Rumble Fax+1.416.978.4711 Tel. +1.204.474.7413 Geophysical Laboratory email: [email protected]. utoron to.ca Fax + 1.204.47 4. 7623 5251 Broad Branch Rd., NW email: [email protected] Washington, D.C. 20013-1305 USA Tel. + 1.202.686.2410 ext. 2483 Fax +1.202.686.2419 email: [email protected]

11 PREFACE Recent technological advances have made possible the This volume, like the course, is divided into four topical sampling and geochemical analysis of increasingly smaller sections: Geochronology and Radiogenic Isotopes, Stable masses of crystalline material. The application of these Isotopes, Elemental Analysis, and Fluid Inclusions. Each new microanalytical te chniques to minerals and rocks chapter represents an overview of the technique utilized opens up a level of detailed geological information that and its practical applications to understanding mineral­ was heretofore masked by more primitive bulk sampling and -forming processes. It is clear that some tech­ techniques. We can now conduct in situ sampling and niques are further along than others in terms of specific analysis of individual growth bands within crystals, and of applications, but all of them are promising and have high tiny solid and fluid inclusions trapped within crystal lat­ potential fo r making important contributions to geologic tices, in many cases determining not only their composi­ knowledge. We hope that the volume makes members of tion but also their time of fo rmation. the geologic community more aware of the microanalyti­ Because of these advances and their potential for assist­ cal techniques and the potential applications to their own ing in attaining a better understanding of min­ specific geologic research problems. eralizing processes, the Society of Economic Geologists The conveners and editors are indebted to all of the au­ held a short course in October 1996 to highlight the di­ thors for their timely efforts in the production of the short verse applications of these techniques. Attended by more course and the resulting volume. than 85 people at The Nature Place Resort in Florissant, Colorado, the course brought together scientists from Australia, Europe, North America, and South Mrica. It was Michael A. McKibben the largest short course ever held by the SEG in conjunc­ W.C. (Pat) Shanks, III tion with a GSA annual meeting. W. Ian Ridley

iii BIOGRAPHIES

LOUIS J. CABRI is principal at Canada Centre for multiple collector inductively coupled plasma mass spectrome­ Mineral and Energy Technology, Ottawa, and has performed try and its application to the origin and early history of the research in applied to ores and characterization of solar system, studies of crustal fluid flow, and paleoceanogra­ various industrial wastes over the past 34 years. He has been in­ phy. volved in the development of new microanalytical techniques for surface analysis and trace-element analyses of minerals, es­ K. V. HODGES is a professor of geology and Dean for pecially for precious metals. Cabri has also been a consultant Undergraduate Curriculum at the Massachusetts Institute of on trace-element analytical techniques and mineralogical bal­ Technology. He received his B.Sc. from the University of North ances, for base metals, gold, silver, and platinum-group ele­ Carolina in 1978 and his Ph.D. from the Massachusetts ment ores, to industry, governments, and universities, on an Institute international level. His work has been published in 145 peer­ of Technology in 1982. Much of his research focuses on the reviewed journals, and he is the winner of SEG Lindgren relationships among thermal, deformational, and erosional award in1965, the Mineralogical Association of Canada's Past­ processes during the evolution of mountain ranges. In the field 4 Presidents' Medal, and the Leonard G. Berry Medal. Cabri is a of 0Arj39Ar thermochronology, recent projects include ex­ fellow of the Royal Society of Canada, Academy of Sciences. ploring the time-temperature histories of metamorphic com­ plexes in the Himalaya, East Greenland Caledonides, Irish J. L. (lAIN) CAMPBELL is a professor of physics at the Caledonides, and the southwestern United States. He regularly University of Guelph in Canada. His Ph.D. was earned in nu­ collaborates with industrial and academic scientists conducting clear physics in 1967 at the University of Glasgow, which research at the MIT Ar isotope laboratory on studies ranging awarded him the D.Sc. in 1982; he received an honorary D. from establishing the provenance of fill, to Tech. degree from the University of Lund in 1997. His research high-resolution dating of volcanic rocks, to in situ dating of de­ deals with inner-shell atomic processes and application of X-ray formational fabrics in low-grade metamorphic rocks. spectroscopy to chemical analysis. Campbell is one of the prin­ cipal developers of the PIXE technique, focusing mainly on JIM J. IRWIN obtained his B.Sc. in geology from McGill trace element analysis and imaging in the geochemical and University, Montreal, in 1980, and Ph.D. in geology from the mineralogical context, in which he has collaborated with a University of California, Berkeley, in 1986. Between 1986 and wide range of Earth scientists. He is co-authorof the text PIXE: 1992 he was a research fellow in the Department of Physics at A novel technique for elemental analysis and Particle-Induced X-ray Berkeley, developing microstandards and studying fluid inclu­ Emission Spectrometry, as well as over 150 journal publications. sions associated with a wide range of ore deposits and geologic settings using the laser microprobe noble gas mass spectro­ GERRY CZAMANSKE was an undergraduate at the University metric approach. He worked as a project scientist at Scripps of Chicago and received his Ph.D. from Stanford University in Institution of Oceanography, San Diego, from 1992 to 1994. 1960. Mter two years of post-doctoral study and three years as Since 1994 he has resided in Vancouver, British Columbia, ac­ an Assistant Professor at the University of Washington, he was tive as a consultant to and director of companies in the re­ recruited by the U.S. Geological Survey and hired full-time in source exploration industry. 1965 as a Geologist GS-12, attaining grade GS-15 in 1978. During his 31-year career with the USGS, he carried out a ADRIENNE LAROCQUE is an assistant professor in the broad range of field and laboratory research activities. Major Department of Geological Sciences at the University of areas of active research included study of the processes of mag­ Manitoba. She received her Ph.D. from Queen's University in matic evolution and ore formation trough use of comprehen­ Ontario in 1993. Her thesis on the topic of metamorphic re­ sive chemical analyses and application of the electron micro­ mobilization in a gold-rich Archean VMS deposit was super­ probe to characterize silicate and sulfide mineral phases; vised by CJ. Hodgson and Louis Cabri. Adrienne made exten­ utilization of new techniques to better analyze geologic mate­ sive use of SIMS (secondary-ion mass spectrometry) for her rials; and, in later years, studies of the ore deposits, flood vol­ doctoral work, and since then has gone on to apply SIMS in canism, and geologic framework of the Noril'sk-Talnakh re­ other areas of geochemical research. Before taking up her po­ gion of north-central Siberia. sition in Manitoba, Larocque was a Director's Postdoctoral Fellow at Los Alamos National Laboratory. There she worked N. studied geology and then geophysics at ALEX HALLIDAY with Don Hickmott on ion implantation for standardization of the University of Newcastle-upon-Tyne, U.K In 1976 he moved SIMS analyses, and studied metal residence and mobility in vol­ to the Scottish Universities Research and Reactor Centre canic systems with Fraser Goff. Larocque continues to use var­ where he a post-doctoral fellow, then a lecturer. A profes­ was ious microbeam techniques to study base- and precious-metal sor at the University of Michigan from 1986 to 1998, Halliday mobility and accumulation in magmatic and hydrothermal sys­ was recently appointed as a professor at ETH Zurich, tems. Switzerland. For many years Halliday worked in three distinct areas of isotope and trace element geochemistry-studies of F. E. UCHTEreceived his B.A. degree from Wartburg College, silicic , crustal fluid flow, and the mantle. In particular, Waverly, Iowa in 1963, and his Ph.D. from Colorado State he has developed several new approaches to the isotopic dat­ University, Ft. Collins, Colorado in 1973. He has been involved ing of diagenetic assemblages and hydrothermal mineraliza­ in the development of instrumental methods of analysis for 35 tion. Most of his recent work involves the new technique of years. During his career, he has worked for Sinclair Oil,

IV BIOGRAPHIES (continued)

Atlantic Richfield, the Environmental Trace Substances Center experimental simulation of magmatic-ore systems (involving at the University of Missouri, and for the U.S. Geological Au, Cu, etc.). He employs a multidimensional approach Survey for the past 20 years. During his tenure with the USGS, involving field observations, modeling, and experimentation, he has been a key researcher in the development of the in­ to solve problems in ore-genesis. ductively coupled plasma for the elemental analysis of geologic R. RICIPUTI received a B.S. degree in geology from materials. He has worked with ICP mass spectrometric tech­ LEE Carleton College in 1985 and M.S. and Ph.D. degrees in nique development for the past 15 years, and laser ablation Geology from the University of Wisconsin-Madison in 1987 and ICP-MS for the past 8 years. He retired in December of 1997 1991. Mter spending two years in a joint research appointment and is currently enjoying his hobbies. at Oak Ridge National Laboratory (ORNL) and the University JOHN MAVROGENES holds a Ph.D. in geology from VPI&S, of Tennessee-Knoxville, he joined the research staffat ORNL and is currently a Lecturer/Research Fellow in Economic full-time, and is currently a staff scientist in the Chemical and Geology at the Australian National University in Canberra Analytical Sciences Division. His current research focuses on ap­ Australia. His work concentrates on experimental studies of plication of secondary-ion mass spectrometry to investigate mi­ ore-forming processes, particularly the analysis of dissolved croscale stable isotope and trace element distributions in order metals in synthetic fluid inclusions. He works on a wide range to better understand mass transport processes in geologic set­ of ore deposits, including porphyry Cu deposits, and experi­ tings using both natural and experimental samples. Riciputi is mental studies of sulfide saturation in komatiites and melting also interested in improving analytical capabilities through a relations in high-metamorphic grade sulfide deposits. better understanding of the fundamentalsputtering/ionization processes occurring in secondary-ion mass spectrometry. MICHAELA. MCKIBBEN received his Ph.D. in geochemistry and a and mineralogy from the Pennsylvania State University in W. IANLEY RID received a B.Sc. in geology in 1964 1984. Since then he has been on the faculty at the University of Ph.D. in geology in 1968 from the University of London, fol­ California at Riverside, where he teaches and conducts re­ lowing volcanologic studies in the Canary Islands. From 1970 to 1973 he involved with astronaut training search in the areas of economic geology and geochemistry. He was and studies of has published several papers and book chapters on ore-forming lunar rocks at the Johnson Space Center, Houston. Until 1980, processes in the Salton Sea geothermal system, and on using Ridley was Associate Professor of Geology at Columbia ion microprobe sulfur isotope data to decipher ore-forming University, with research interests in , lunar petrol­ processes in sedimentary, geothermal and volcanic systems. ogy, and analytical techniques. He has organized and super­ McKibben has served on the editorial boards of Economic vised several analytical laboratories for XRF, XRD, SEM, EMP, Geology and Geochimica et Cosmochimica Acta, and as a and lately for laser ablation ICP-MS. He is currently a research Councillor for the Society of Economic Geologists. He also geologist with the U.S. Geological Survey, Denver. serves as a consultant to and geothermal companies DOUGLAS RUMBLE is a geologist with the Geophysical exploring for metalliferous brines. Laboratory, Carnegie Institution of Washington. He was edu­ cated at Columbia College (B.A., 1964) and Harvard JILL DILL PASTERIS received her in University (Ph.D., 1969). His research interests include de­ geology from Bryn Mawr College in 1974. She then spent a signing and building new laser systems for analyzing isotopes in year studying ore microscopy at the University of Heidelberg, minerals and field, petrologic, geochemical, and tectonic Germany, working under Dr. Paul Ramdohr. In 1980, she com­ analysis of coesite- and diamond-bearing ultra-high pressure pleted a Ph.D. at Yale University, doing thesis research on the metamorphic rocks in China and Kazakhstan. opaque oxide phases of a kimberlite pipe in South Mrica. In the same year, she joined the faculty of the Earth and Planetary W. C. (PAT) SHANKS, III, received his Ph.D. from the Sciences department at Washington University in St. Louis, University of Southern California, where he worked with Jim where she has remained. Her work involves various aspects of Bischoff on the geochemistry of the Red Sea brine pools and fluid-rock interactions as they pertain to igneous and meta­ associated metalliferous deposits. Shanks was involved in geo­ morphic rocks and, especially, to the formation of igneous ore chemical studies of the initial massive sulfide discovery at 21N deposits. She and her students have focused on Cu-Fe-Ni­ on the East Pacific Rise, and has spent many years studying sulfide and Fe-Ti-oxide deposits. With colleague Brigitte seafloor hydrothermal systems. In 1988, Shanks and Bob Criss Wopenka, Pasteris set up a laser Raman microprobe laboratory of the U.S. Geological Survey organized an internationalwork­ in 1983, which they have used for the study of natural fluid in­ shop on the use of lasers and ion probes in stable isotopic clusions, synthetic fluid inclusions and gas mixtures, micro­ analyses. The proceedings of this workshop were published as samples of solid phases, and specific types of aqueous fluids. U.S. Geological Survey Bulletin 1890, and set the stage for many of the discoveries presented in this volume. PHILIP M. PICCOU is a research scientist at the Laboratory for Mineral Deposits Research, University of Maryland. His in­ ZACHARY SHARP received his bachelor's degree from the terests include field studies of silicic volcanic and plutonic University of California at Berkeley, and a Ph.D. from the rocks; the use of accessory phases in the determination of University of Michigan. Sharp joined the Carnegie Institution magmatic, hydrothermal, and ore-forming processes; chemical of Washington as a post-doctoral fellow, working closely with modeling of ore-forming processes; microanalysis of minerals; Doug Rumble. He spent eight years as a research scientist

v BIOGRAPHIES (continued)

at the University of Lausanne, Switzerland, and recently faculty at Georgia State University in Atlanta, where he is joined the Department of Earth and Planetary Sciences at currently professor and department head. His research has the University of New Mexico as an Associate Professor. Sharp focused on the of hydrothermally altered rocks from is a stable isotope geochemist, and has developed a number of the ocean crust, with special emphasis on the use of fluid in­ analytical techniques for stable isotope analysis of solids using clusion studies to understand hydrothermal processes. laser ablation. His present research interests involving stable S. WILLIAMS is a fellow at the Research School of Earth isotopes are wide-ranging, and include studies of metamorphic IAN Sciences, Australian National University. Mter receiving his and igneous rocks, , paleoclimate research, Ph.D. in isotope geochemistry from the ANU in 1978, he stud­ and modern animal physiology. ied U-Pb geochronology at the California Institute of JOHN W. VALLEY received his A.B. from Dartmouth College, Technology, then returned to the ANU to help develop tech­ and his M.S. and Ph.D. in geology from the University of niques for U-Pb isotope analysis using the newly-constructed Michigan in 1980. From 1989 to 1990, he was a Fulbright SHRIMP I ion microprobe. He joined the faculty at RSES in Scholar at the University of Edinburgh. He is presently profes­ 1992. Williams has a broad interest in the application of ion mi­ sor and Chair of the Department of Geology and Geophysics, croprobe analysis in the geosciences, and a particular interest University of Wisconsin-Madison. His research in metamor­ in utilizing differences in the micro-scale behavior of mineral phic petrology and geochemistry has included many studies of U-Th-Pb isotope systems under diverse geological conditions to the role of fluids during and hydrothermal re­ determine the origin, age, and thermal history of the Earth's action. Valley co-edited the MSA Reviews in Mineralogy vol­ crust, focusing especially on the early Earth, granite genesis, ume, Stable Isotopes in High Temperature Processes and and polymetamorphic . wrote a chapter on metamorphism. Since 1987, he has been ac­ GRAHAM C. WILSON holds a part-time post as a research as­ tive in development and applications of new techniques for mi­ sociate of the IsoTrace Laboratory at the University of Toronto. croanalysis of stable isotopes by laser probe and by ion micro­ He received a B.A. (Hons.) degree in geology and mineralogy probe. He is author of over 100 scientific articles and 200 from the University of Oxford and a Ph.D. from Cambridge. abstracts, has served as Associate Editor for GSA Bulletin, His wide-ranging interests in economic geology and petrology Journal of Geophysical Research, and American Journal of are addressed in part through the application of in situ elec­ Science. Valley has also served on numerous committees and as tron, proton, and ion-beam analytical methods, including ac­ a member of Council for MSA. He has been on review panels celerator mass spectrometry. These methods are used to com­ for NSF, DOE, GSA, and the Geochemical Society, and is a fel­ plement more "traditional" work in field geology, petrography, low of MSA and GSA. and geochemistry. Ongoing research interests include the min­ DAVIDA. VANKO received B.A. and M.A. degrees from Johns eralogy of precious- and base-metals deposits and the develop­ Hopkins University and a Ph.D. in Geological Sciences from ment of computer databases. Since 1985, Wilson has operated Northwestern University in 1982. Mter a two-yearpost-doctoral a consulting firm, Turnstone Geological Services Ltd, produc­ fellowship at Washington University in St. Louis, he joined the ing approximately 300 geological and mineralogical reports

vi CONTENTS

PART 1: GEOCHRONOLOGY AND RADIOGENICISOTOPES Chapter 5-Laser Microanalysis of Silicates for lSOji70jl60 and of Carbonates for 180/160 Chapter 1-U-Th-Pb Geochronology by Ion Microprobe and l3Cj12C Ratios ABOUT TIME ...... 1 INTRODUCTION ...... 99 RADIOISOTOPE GEOCHRONOLOGY ...... 1 LAsER FLUORINATION OF MINERALS ...... 99 THE ION MICROPROBE ...... 2 METHODS OF ANALYSIS . 102 GEOCHRONOLOGY BY ION MICROPROBE ...... 3 LAsER ANALYSIS OF CARBONATES...... 1 06 THE SENSITIVE HIGH MAss REsoLUTION ION APPLICATIONS OF THE GC-IRMMS LAsER METHOD

MICROPROBE ...... 5 TO OTHER PHASEs; FuTURE PossiBILITIEs ...... 113 U-TH-PB ANALYSIS BY SHRIMP...... 9 APPLICATIONS TO QUARTZ AND TO SHRIMP U-TH-PB GEOCHRONOLOGY IN PRACTICE ...... 19 QUARTZ-CALCITE VEINS ...... 114 FUTURE PROSPECTS ...... 30 REFERENCES ...... 116 ACKNOWLEDGMENTS ...... 32 REFERENCES ...... 32 Chapter 6-Sulfur Isotopes by Ion Microprobe INTRODUCTION ...... 121 Chapter 2-ICP Multiple-Collector Mass Spectrometry INSTRUMENTAL AND TECHNIQUE CONSIDERATIONS ...... 121 and In Situ High-Precision Isotopic Analysis GRAPHICAL DEPICTION AND EVALUATION OF

OVERVIEW ...... 37 ISOTOPIC GROWTH ZONING IN CRYSTALS ...... 126 INTRODUCTION ...... 37 APPLICATIONS ...... 131 ICP MAGNETIC SECTOR MULTIPLE-COLLECTOR ACKNOWLEDGMENTS ...•....•...... •...... 138 MAss SPECTROMETRY ...... 38 REFERENCES ...... 138 LAsER ABLATION MC-ICPMS ...... 40 APPLICATION OF MC-ICPMS TO STUDIES OF Chapter 7-Sulfur Isotope Analyses Using the

CRUSTAL FLUID FLOW...... 46 Laser Microprobe FUTURE DEVELOPMENTS OF MC-ICPMS...... 47 INTRODUCTION ...... 141 ACKNOWLEDGMENTS ...... : ...... 47 ANALYTICAL METHODS ...... 142 REFERENCES ..•....•...... •...•...•...... •...•...... •...... 48 APPLICATIONS ...... 148 ORE DEPOSITS ...... •...... •...... 150 Chapter 3-40Arj39Ar Geochronology Using the CONCLUSIONS ...... 151 Laser Microprobe REFERENCES ...... 152 INTRODUCTION ...... , ...... 53 ESSENTIALS OF 40ARj39AR GEOCHRONOLOGY ...... 53 PART III: ELEMENTALANALYSIS ELEMENTS OF AN 40ARj39AR lABORATORY ...... 58 LAsERS AS TOOLS FOR ARGON EXTRACTION ...... 63 Chapter 8-Ion-Microprobe Quantification of APPLICATIONS ...... •....•....•...... •... 65 Precious Metals in Sulfide Minerals 40ARj39AR MICROANALYSIS AND ECONOMIC GEOLOGY...... 69 GENERAL PRINCIPLES ...... 155 THE FUTURE ...... 70 DATA PRESENTATION ...... 156 ACKNOWLEDGMENTS ...... 70 STANDARDIZATION ...... 157 REFERENCES ...... 70 ANALYSIS ...... •...... 158 APPLICATIONS TO GEOLOGICAL AND

METALLURGICAL PROBLEMS ...... PARTII: STABLE IsOTOPES . 162 ACKNOWLEDGMENTS ...... 164 Chapter 4-Ion Microprobe Analysis of Oxygen, Carbon, REFERENCES ...... 164 and Hydrogen Isotope Ratios APPENDIX 1: DATA REDUCTION FOR INTRODUCTION ...... 73 IMPLANTED STANDARDS ...... •...... •...... 167 THE ION MICROPROBE/SECONDARY ION APPENDIX II: ACRONYMS USED IN TEXT ...... 167 MAss SPECTROMETER ...... 7 4 TECHNIQUE ...... 75 Chapter 9-Micro-PIXE in TECHNIQUE-CARBON...... 82 FuNDAMENTALS...... •...... 169 TECHNIQUE-HYDROGEN ...... 83 APPLICATIONS ...... 176 PROCESSES CAUSING INTRA-CRYSTALLINE ACKNOWLEDGMENTS ...... 183 ISOTOPE HETEROGENEITY ...... 84 REFERENCES ...... 184 CASE STUDIES-OXYGEN ...... 86 CASE STUDIES-CARBON ISOTOPES ...... 93 CASE STUDIEs-HYDROGEN ...... 94 ACKNOWLEDGMENTS ...... •••...... •...•94 REFERENCES ...... 95

vii Chapter 1 0-Economic Applications of Accelerator Chapter 13-The Laser Raman Microprobe as a Mass Spectrometry Tool for the Economic Geologist ACCELERATOR MAss SPECTROMETRY ...... 187 INTRODUCTION ..•...... •.••....••...... •...... •.•.•...... 233 APPLICATIONS TO ORE MINERALS AND How CAN RAMAN SPECTROSCOPY FULFILL THE MINERAL DEPOSITS ...... 190 ECONOMIC GEOLOGIST'S NEEDS? ...... 233 APPLICATIONS TO GANGUE MINERALS ...... 192 RAMAN SPECTROPSCOPIC ANALYSIS AND PLANNING THE RUN, INTERPRETING THE RESULTS ...... J93 INTERPRETATION ...... •...... •..•..•.•.•.•...... 236

...... CONCLUDING REMARKS ...... 194 SELECTED RAMAN APPLICATIONS TO ORE DEPOSITS 241 ACKNOWLEDGMENTS ...... •...... •....•....•...... ••...... 196 WHERE WILL RAMAN SPECTROSCOPY TAKE REFERENCES ...... 196 ECONOMIC GEOLOGISTS IN THE FuTURE? ...... 24 7 ACKNOWLEDGMENTS ••....•...•.•...... •..•...... •.....•...... •...... • 248 Chapter 11-Major, Trace, and Ultratrace Element REFERENCES ...... 248 Analysis by Laser Ablation ICP-MS INTRODUCTION ...... 199 Chapter 14-Synchrotron-Source X-ray Fluorescence THE TECHNIQUE ...... 199 Microprobe: Analysis of Fluid Inclusions QUANTITATIVE GEOCHEMICAL ANALYSIS...... 203 INTRODUCTION ...... 251 APPLICATIONS OF LA-ICP-MS ...... 205 PRACTICAL AsPECTS OF SXRF MICROPROBE POSTSCRIPT ...... 213 ANALYSIS OF FLUID INCLUSIONS ...... 254 ACKNOWLEDGMENTS ...... •...... •...... •.•...... 213 ACKNOWLEDGMENTS .....•.....•....•...... •...... •...... 262 REFERENCES ...... 213 REFERENCES ...... •...... •.....•...... •...... ••.. 262

PART IV:FLUID INCLUSIONS

Chapter 12-Evidence for Sources of Salinity and Dissolved Gases, Fluid Mixing and Phase Separation, from Laser Microprobe Analysis of Cl, K, Br, I Ar, Kr, and Xe in Fluid Inclusions INTRODUCTION ...... 217 METHODS ...... 217 OVERVIEW ...... 219 MAGMATIC FLUIDS ...... 222 FLUID INCLUSIONS THAT CONTAIN METEORIC WATER ..... 223 METAMORPHIC FLUIDS ...... 227 EVIDENCE OF PROCESSES IN ANCIENT

HYDROTHERMAL SYSTEMS ...... 228 SUMMARY ...... 228 ACKNOWLEDGMENTS ...... •...... •...... •...... •..229 REFERENCES ...... •...... •....•...... •...... 229

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