DOCSLIB.ORG

Carbonatites, Nepheline Syenites, Kimberlites and Related Rocks;In British Columbia

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Carbonatites, Nepheline Syenites, Kimberlites and Related Rocks;In British Columbia Province of British Columbia MINERAL RESOURCES DIVISION Ministry of Energy, Mines and Geological Survey Branch Petroleum Resources Hon. Anne Edwards, Minister CARBONATITES, NEPHELINE SYENITES, KIMBERLITES AND RELATED ROCKS;IN BRITISH COLUMBIA This is a Contribution to the CanaddBritish Columbia Mineral Development Agreement1985-1990 By Jennifer Pel1 BULLETIN 88 Canadian~~ ~~~~~~~ Catalooulno~ -~ in Publication Data Pell, Jennifer,1956- Carbonatites, nepheline syenites, kimberlites and relatedrocks in British Columbia (Bulletin, ISSN 0226-7497 ;88) Issued byGeologicalSurveyBranch. 'This is a Contribution to the CanadaIBritisb Columbia Mineral Development Agreement 1985-1990." Indudes bibliographical references: p. ISBN 0-77262170-5 1. Carbonatites -British Columbia. 2. Nepheline Field Research furthis project was caniec! uut syenite -British Columbia. 3. Kimberlite - British durizgtheperiod 1984 to 1990 Columbia. 4. Geology, Economic - British Columbia. 5. Geochemistry - British Columbia, 6.Petrology - British Columbia. I. British Columbia. Ministry of Energy, Mines and Petroleum Resources. 11. British Columbia. GeologicalSurveyBranch. 111. CanadalBritish Columbia Mineral Development Agreement. IV. Title. V. Series: VICTORIA Bulletin (British Columbia. Ministry of Energy, Minesand BRITISH COLUMBIA Petroleum Resources) ; 88. CANADA TN27.B7P44 1994 553.6'09711TN27.B7P44C94-960219-1 1994 July 1994 Ministry of Energx Minesand Petroleum Resources TABLE OF CONTENTS” INTRODUCTION........................................................................ 1 Geochemistry...................................................... 36 Distributiongeneral and characteristics of Geochronology ................................................... 36 carbonatites and nephelinesyenites .................... 2 Distribution and general characteristics of CARBONATITES AND SYENITE GNEISS COMPLliXES IN METAMORPHOSED PRECAMBRIAN EARLY kimberlites and alkaline ultrabasic diatreme TO CAMBRIAN STRATA. OMINECA BELT ............................... 31 breccias ................................................................ 3 Manson Creek area (93N/9) ..................................... 37 Geological work .......................................................... 5 Carbonatites ........................................................ 37 Acknowledgments....................................................... 5 phases 38 Silicate phases ..................................................... Fenites ................................................................. 38 CARBONATITE AND SYENITE COMPLEXES IN Geochemistry ...................................................... 39 PALEOZOIC STRATA, ROCKYAND CASSIAR Geochronology ................................................... 40 MOUNTAINS. FORELANDBELT ............................................ 7 Mount Bisson- Mnnroe Creekarea (93N/9; The Aley Carbonatite complex(94B/5) ...................... 7 930/5. 12).......................................................... 41 Rauhangite core zone............................................ 41 7 rocks Alkalic dike ............................................... Sovite zones........................................................... 7 Pegmatites........................................................... 42 ‘Am phibolitic’ margin ‘Amphibolitic’ ........................................... 7 Intrusive breccias ................................................ 42 Alteration halo ....................................................... 8 Fenites ................................................................. 42 Rare-earth-bearing dikes ..................................... 11 Quartz monzonitesand quartz syenites ..............42 Geochemistry ...................................................... 11 Geochemistry...................................................... 42 Geochronology.................................................... 11 Geochronology ................................................... 43 Wicheeda Lake complex(Prince and George Blue Riverarea (83D/3. 6. 7) ................................... 43 claims, 93V5; 93J/8, 9) 11 ...................................... Carbonatites ........................................................ 44 Carbonatites andassociated syenitic rocks .........13 Nepheline syenites .............................................. 44 Alkaline dikes ...................................................... 13 Mafic Silicate Rocks ........................................... 44 Geochemistry ...................................................... 13 Fenites ................................................................ 47 Geochronology.................................................... 14 Geochemistry ..................................................... 47 BearpawRidge sodalite syenite (93V4).................... 14 Geochronology .................................................. 53 Sodalite syenite ................................................... 15 Trident Mountain (82M/16) .................................... 53 Nonda formationvolcaniclastic rocks ................16 Geochemistry..................................................... 54 Orthogneiss.......................................................... 16 Geochronology .................................................. 54 Postorogenic syenite ........................................... 17 Geochemistry ...................................................... 17 CARBONATITES AND SYENITE GNEISSCOMPLEXES Geochronology.................................................... 18 ASSOCIATED WITH CORE GNEISSES INTHE Oh! INECA Ice River complex (82N/1)....................................... 18 BELT .......................................................................................... 55 Ultramafic series ................................................. 18 Mount Copeland nephelinesyenite gneisses Zoned syenite complex ....................................... 19 (82W2) ............................................................. 55 Carbonatites......................................................... 19 Nepheline syenite gneisses ................................ 55 Lamprophyres ..................................................... 20 Alkaline amphibolite......................................... 58 Geochemistry ...................................................... 22 Grey syenruc.. gneiss ........................................... 58 Geochronology.................................................... 23 Geochemistry ..................................................... 59 Rock Canyon Creekfluorite and rare-earth Geochronology ................................................... 60 element showing(82J13E) ................................. 24 Carbonatites and associated rocks. west flank, Minerahzatlon....................................................... Frenchman Cap 25 dome (82W2, 7, 10) ...............60 Geochemistry ...................................................... 25 Perry River intrusive carbonatites (82Wr)........ 60 Geochronology.................................................... 27 Fenites - Perry River area .................................. 60 Kechika Riverarea (94L/ll, 12, 13) ........................ 27 Ratchford Creek (Ren)intrusive carbona:ite Distribution and field relationships of (82W7) ........................................................ 62 alkaline rocks ............................................... 28 Intrusive syenite - Perry River area Petrography: syenites .......................................... 30 (82W7, 10) .................................................. 62 Petrography: trachytes ......................................... 31 Mount Graceextrusive carbonatite Petrography: (82W7, 10).................................................. 63 feldspar-quartz-carbonate-sericiterocks .....31 Geochemistry ...................................................... 66 Petrography: carbonatites.................................... 34 Geochronology ................................................... 68 _- Bulletin 88 iii Three Valley Gap (82L/16)....................................... 68 Carbonatites and syenite gneisses ........................... 111 Carbonatites, fenites, syenites ............................. 69 Kimberlites. lamprophyres andother ultrabasic Geochemistry....................................................... 70 diatremes.............................................................. 111 Geochronology .................................................... 70 Tectonlc lmphcattons .............................................. 113 ULTRABASIC DIATREMESIN NORTHERN BRITISH REFERENCES ........................................................................ 119 COLUMBIA............................................................................... 71 The Kechika River diatreme andrelated rocks APPENDICES ......................................................................... 125 (94L/12, 13)........................................................ 71 COLOUR PHOTOS ................................................................. 135 Lithology ............................................................. 71 Geochemistry....................................................... 73 FIGURES Geochronology .................................................... 74 1. Index map, carbonatite and syenite gneiss Ospika Pipe(94B/5) .................................................. 74 complexes ..................................................................... 2 Lithology ............................................................
Load more

Recommended publications
  • Minor Elements in Magnetic Concentrates from the Syenite-Shonkinite Province, Southern Asir, Kingdom of Saudi Arabia
    DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Minor elements in Magnetic concentrates from the Syenite-Shonkinite Province, Southern Asir, Kingdom of Saudi Arabia I/ I/ I/ I/ W. C. Overstreet, G. W. Day, Theodore Botinelly, and George Van Trump, Jr. Open-File Report 87 r Report prepared by the U.S. Geological Survey in cooperation with the Deputy Ministry for Mineral Resources, Saudi Arabia This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature, I/ USGS, Retired 2/ USGS, Denver, CO 1987 CONTENTS ABSTRACT............................................................ 1 ACKNOWLEDGMENT...................................................... 1 INTRODUCTION........................................................ 1 Areas covered and previous work................................ 1 Syenite plutons........................................... 3 Jabal Fayfa and Jabal Bani Malik..................... 3 Pluton southeast of Suq al Ithnayn................... 3 Shonkinite pluton at Jabal Atwid..................... 3 Mineral potential......................................... 3 Purpose of present investigation............................... 3 PROCEDURES.......................................................... 10 Collection and preparation of detrital magnetite............... 10 Mineralogical analyses......................................... 10 Semiquantitative spectrographic analyses....................... 11 Method...................................................
    [Show full text]
  • Summary of the Mineral Information Package for the Khanneshin Carbonatite Area of Interest
    Chapter 21A. Summary of the Mineral Information Package for the Khanneshin Carbonatite Area of Interest Contribution by Robert D. Tucker, Harvey E. Belkin, Klaus J. Schulz, Stephen G. Peters, and Kim P. Buttleman Abstract The Khanneshin carbonatite is a deeply dissected igneous complex of Quaternary age that rises approximately 700 meters above the flat-lying Neogene sediments of the Registan Desert, Helmand Province, Afghanistan. The complex consists almost exclusively of carbonate-rich intrusive and extrusive igneous rocks, crudely circular in outline, with only three small hypabyssal plugs of leucite phonolite and leucitite outcropping in the southeastern part of the complex. The complex is broadly divisible into a central intrusive vent (or massif), approximately 4 kilometers in diameter, consisting of coarse-grained sövite and brecciated and agglomeratic barite-ankerite alvikite; a thin marginal zone (less than 1 kilometer wide) of outwardly dipping (5°–45°). Neogene sedimentary strata; and a peripheral apron of volcanic and volcaniclastic strata extending another 3–5 kilometers away from the central intrusive massif. Small satellitic intrusions of biotite-calcite carbonatite, no larger than 400 meters in diameter, crop out on the southern and southeastern margin of the central intrusive massif. In the 1970s several teams of Soviet geologists identified prospective areas of interest for uranium, phosphorus, and light rare earth element (LREE) mineralization in four regions of the carbonatite complex. High uranium concentrations are reported in two regions; the greatest concentrations are confined to silicified shear zones in sandy clay approximately 1.1 kilometers southwest of the peripheral part of the central vent. An area of phosphorus enrichment, primarily occurring in apatite, is present in coarse-grained agglomeratic alvikite, with abundant fenite xenoliths, approximately 750 meters south of the periphery of the central vent.
    [Show full text]
  • Feldspar and Nepheline Syenite 2016
    2016 Minerals Yearbook FELDSPAR AND NEPHELINE SYENITE [ADVANCE RELEASE] U.S. Department of the Interior January 2020 U.S. Geological Survey Feldspar and Nepheline Syenite By Arnold O. Tanner Domestic survey data and tables were prepared by Raymond I. Eldridge III, statistical assistant. In 2016, feldspar production in the United States was representing 46% of the 2016 production tonnages listed in estimated to be 470,000 metric tons (t) valued at $33.1 million, tables 1 and 2. an almost 10% decrease in quantity and a 11% decrease in Feldspar was mined in six States (table 3). North Carolina value compared with 2015 (table 1). Exports of feldspar in 2016 was by far the leading producer State; the remaining five were, decreased by 61% to 5,890 t, valued at $1.5 million, and imports in descending order of estimated output, Virginia, California, of feldspar decreased by 69% to 36,900 t, valued at $3.4 million. Idaho, Oklahoma, and South Dakota. Production was from Imports of nepheline syenite (predominantly from Canada) 10 mines and beneficiating facilities—4 in North Carolina, 2 in increased by 27% to about 572,000 t valued at $73 million. California, and 1 in each of the 4 remaining States (table 3). World production of feldspar in 2016 was 23.4 million metric I-Minerals Inc. continued the mine permitting process for tons (Mt) (tables 1, 7). its Helmer-Bovill project in north-central Idaho; the mine Feldspars, which constitute about 60% of the earth’s crust, would produce potassium feldspar, halloysite, kaolin, and are anhydrous aluminosilicate minerals of two main groupings: quartz.
    [Show full text]
  • Pamphlet to Accompany Scientific Investigations Map 3131
    Bedrock Geologic Map of the Seward Peninsula, Alaska, and Accompanying Conodont Data By Alison B. Till, Julie A. Dumoulin, Melanie B. Werdon, and Heather A. Bleick Pamphlet to accompany Scientific Investigations Map 3131 View of Salmon Lake and the eastern Kigluaik Mountains, central Seward Peninsula 2011 U.S. Department of the Interior U.S. Geological Survey Contents Introduction ....................................................................................................................................................1 Sources of data ....................................................................................................................................1 Components of the map and accompanying materials .................................................................1 Geologic Summary ........................................................................................................................................1 Major geologic components ..............................................................................................................1 York terrane ..................................................................................................................................2 Grantley Harbor Fault Zone and contact between the York terrane and the Nome Complex ..........................................................................................................................3 Nome Complex ............................................................................................................................3
    [Show full text]
  • Introduction to Igneous Petrology
    Cambridge University Press 978-1-107-02754-1 - Essentials of Igneous and Metamorphic Petrology B. Ronald Frost and Carol D. Frost Excerpt More information Chapter 1 Introduction to Igneous Petrology 1.1 Introduction Igneous petrology is the study of magma and the rocks that solidify from magma. Th us igneous petrologists are concerned with the entire spectrum of processes that describe how magmas are produced and how they ascend through the mantle and crust, their mineralogical and geochemical evolution, and their eruption or emplacement to form igneous rocks. Igneous petrology requires a working knowledge of mineralogy. Readers who wish to review the characteristics of the major rock-forming igneous minerals will fi nd a concise sum- mary in Appendix 1. Th e appendix emphasizes the identifi cation of rock-forming minerals in hand sample and in thin section. In addition, the appendix includes descriptions of minerals found in minor abundance but commonly occurring in igneous rocks, including accessory minerals that contain trace amounts of uranium and are important geochronometers. Before geologists can understand the origin of igneous rocks, they must classify and describe them. Th is chapter introduces the classifi cation of igneous rocks using the mineralogical classifi cation system recom- mended by the International Union of Geological Sciences (IUGS) Subcommission on the Systematics of Igneous Rocks, which has the advantage that it is relatively simple and can be applied in the fi eld. For rocks that are too fi ne-grained to name using this classifi cation, a geochemical classifi cation can be employed instead. Th e simplest of these, the total alkali versus silica classifi cation, is introduced in this text.
    [Show full text]
  • Benefits of Utilizing Nepheline Syenite in Porcelain Tile
    1 BENEFITS OF UTILIZING NEPHELINE SYENITE IN PORCELAIN TILE AND SANITARYWARE Anais do 48º Congresso Brasileiro de Cerâmica Proceedings of the 48th Annual Meeting of the Brazilian Ceramic Society 28 de junho a 1º de julho de 2004 – Curitiba-PR SCOTT E. BARTON UNIMIN CORPORATION 500 WILSON PIKE CIRCLE, SUITE 127 BRENTWOOD, TENNESSEE 37027 USA EXECUTIVE SUMMARY Nepheline syenite is a commercially prepared, rare feldspathoid-rich rock product that contributes both potassium and sodium oxides to the ceramic formulation. It has been used in both North America and Europe for the production of porcelain tile and sanitaryware for many years. It is the unique mineralogy and high levels of alkalis of nepheline syenite that justify its use in ceramics. These characteristics promote lower firing temperatures that can enhance productivity and lower production costs. Depending on location, the use of nepheline syenite can lower raw material cost by allowing more silica to be used in the formulation. Additionally, the process control found in most nepheline syenite operations offers a controlled level of Fe2O3 that can help to improve fired color. The goal of this study is to illustrate the practical benefits of using nepheline syenite for the vitrification in a ceramic body formulation. Keywords: nepheline syenite, porcelain, tile, feldspar, sanitaryware INTRODUCTION As the porcelain tile and sanitaryware industries continue to globalize, manufacturers must continually improve the control and quality of their raw materials to effectively compete on the global scale. To do so, many manufacturers must look not only at domestic materials but also at external sources for these important requirements of quality and consistency.
    [Show full text]
  • Controls on Syenite-Hosted Gold Mineralization in the Western Timmins Camp
    Western University Scholarship@Western Electronic Thesis and Dissertation Repository 11-24-2014 12:00 AM Controls on Syenite-Hosted Gold Mineralization in the Western Timmins Camp Robert A. Campbell The University of Western Ontario Supervisor Bob Linnen The University of Western Ontario Graduate Program in Geology A thesis submitted in partial fulfillment of the equirr ements for the degree in Master of Science © Robert A. Campbell 2014 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Geology Commons Recommended Citation Campbell, Robert A., "Controls on Syenite-Hosted Gold Mineralization in the Western Timmins Camp" (2014). Electronic Thesis and Dissertation Repository. 2636. https://ir.lib.uwo.ca/etd/2636 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Controls on Syenite-Hosted Gold Mineralization in the Western Timmins Camp (Thesis format: Monograph) by Randy Campbell Graduate Program in Earth Sciences A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science The School of Graduate and Postdoctoral Studies The University of Western Ontario London, Ontario, Canada © Randy Campbell 2014 ABSTRACT The Abitibi granite-greenstone belt has long been known for its’ world-class Archean lode gold deposits. While a spatial relationship between felsic intrusions and gold deposits has been noted for some time, it is not clear whether porphyries are genetically related to gold mineralization or just provided a brittle host for unrelated mineralization.
    [Show full text]
  • Igneous Textures and Structures
    GLG 333 -- IGNEOUS TEXTURES AND STRUCTURES The following is a reorganization and amplification of Blatt, Tracy, and Owens, 2006, pages 29-35. (You may also want to refer to Barker, 1983, pages 106-120; Hyndman, 1985, pages 49-61; or Jackson, 1970, pages 255-273 and 317-323. You will also definitely want to look at MacKenzie et al., 1982, pages 4-73, to see what these igneous textures look like when viewed in thin-section under a petrographic microscope.) I. SHAPE OF INDIVIDUAL CRYSTALS (indicates sequence of crystallization) A. Euhedral. Crystal completely bounded by its own crystal faces. Indicates early crystallization from the magma, i.e. before enough other crystals were present to cause interference for space. B. Anhedral. Crystal not bounded by any of its own crystal faces; rather, its form is imposed on it by the adjacent crystals. Indicates late crystallization from the magma, i.e. after most of the available space was already occupied by earlier-formed crystals. C. Subhedral. Intermediate between euhedral and anhedral. II. GENERAL ROCK TEXTURES A. Based on Degree of Crystallinity 1. Holohyaline. Rock composed entirely of glass; no crystals visible even with magnification. Indicates cooling so rapid that no crystal growth could occur, i.e. quenching. a. Obsidian Massive volcanic glass. b. Pumice Frothy (micro-vesicular) volcanic glass. 2. Hypocrystalline (or Hyalocrystalline). Rock composed of both crystals and glass. a. Pitchstone Volcanic glass with a resinous luster or streaky appearance caused by microscopic crystallites. b. Vitrophyre Volcanic glass with macroscopic phenocrysts. c. Perlite Volcanic glass with a cloudy or milky appearance caused by devitrification.
    [Show full text]
  • Multiple Processes of Geochemical Evolution for the Alkaline Rocks Of
    213213 https://doi.org/10.11606/issn.2316-9095.v20-151049 Revista do Instituto de Geociências - USP Geol. USP, Sér. cient., São Paulo, v. 20, n. 4, p. 221-214, Dezembro 2020 Multiple processes of geochemical evolution for the alkaline rocks of Rio Bonito intrusive complex, Rio de Janeiro State, Brazil: 40Ar/39Ar and U-Pb ages and Lu-Hf isotopes on zircon and constraints on crustal signature Múltiplos processos de evolução geoquímica para as rochas alcalinas do complexo intrusivo de Rio Bonito, Estado do Rio de Janeiro, Brasil: idades 40Ar/39Ar e U-Pb e isótopos Lu-Hf em zircão – considerações sobre assinatura crustal Daniel Adelino da Silva1 , Akihisa Motoki1Ϯ, Anderson Costa dos Santos1 , Julio Mendes2 , Fred Jourdan3 , Mauro César Geraldes1 , Cristiano de Carvalho Lana4 2Universidade do Estado do Rio de Janeiro - UERJ, Departamento de Mineralogia e Petrologia Ígnea, Rua São Francisco Xavier, 524, CEP 20550-900, Rio de Janeiro, RJ, BR ([email protected]; [email protected]; [email protected]); Ϯin memoriam. 2Universidade Federal do Rio de Janeiro - UFRJ, Instituto de Geociências, Rio de Janeiro, RJ, BR ([email protected]) 1University of Technology - GPO, Western Australian Argon Isotope Facility, Department of Applied Geology & JdL Centre, Curtin, Perth, Australia ([email protected]) 4Universidade Federal de Ouro Preto - UFOP, Isotope Geochemistry Laboratory, Ouro Preto, MG, BR ([email protected]) Received on October 22, 2028; accepted on November 6, 2020 Abstract This article presents geochemical characteristics of the alkaline rocks of Rio Bonito intrusive complex, State of Rio de Janeiro, Brazil, which is constituted mainly by nepheline syenite.
    [Show full text]
  • Geology of the Saline County Xenolith and Surrounding Area
    A.G.E.S. Brochure Series 005 State of Arkansas Arkansas Geological Survey Bekki White, State Geologist Geology of the Saline County Xenolith and surrounding area By J. Michael Howard Illustrations and photos by Angela Chandler _______________________________________________________ _______________________________________________________ Xenolith – “ a foreign inclusion in an igneous rock.” Glossary of Geology American Geological Institute 1987 (from the Greek words Xenos, meaning guest or stranger, and Lithos, meaning stone.) _______________________________________________________ _______________________________________________________ Introduction Located in Saline County, Arkansas, at the south edge of the community of Bauxite, this natural outcrop of nepheline syenite contains several geologically interesting features, including a xenolith. Sloping west, the outcrop encompasses about one-quarter acre near the center of section 21, Township 2 South, Range 14 West. In early 1990, the Aluminum Company of America (ALCOA) donated the outcrop along with approximately five surrounding acres of land to the Arkansas Geological Commission so that the site can be preserved for educational purposes. Outcrop of nepheline syenite at xenolith locality. History of the site The outcrop and its geologic features were first described by J. Francis Williams in 1891 in The Igneous Rocks of Arkansas, Arkansas Geological Survey Annual Report for 1890, Volume II. Williams discussed the outcrop and xenolith in some detail and included a sketch of the xenolith (see title page). However, for many years the outcrop location remained unknown to most scientists. In the late 2 1960’s employees in the mining division of ALCOA, suspecting that the site was on their property, began a concerted search. Soon afterward the outcrop was rediscovered and was visited by a staff member of the Arkansas Geological Commission, who in turn told Dr.
    [Show full text]
  • Rare Earth Element Mobility During Conversion of Nepheline Syenite Into Lateritic Bauxite at Passa Quatro, Minais Gerais, Brazil B
    Applied Geochemistry, Vol. 9, pp. 701-711,1994 Pergamon Copyright 01994 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0883-2927/94 $7.00+0.00 0883-2927(94)E0025-5 Rare earth element mobility during conversion of nepheline syenite into lateritic bauxite at Passa Quatro, Minais Gerais, Brazil B. BOULANGÉand F. COLÌN- ORSTOM, UM GECO, Laboratoire de Géosciences de l’Environnement, Université Aix Marseille III, 13397 Marseille CBdex 20, France (Received 10 July 1992; accepted in revised form 4 May 1994) Abstract-In a lateritic bauxite formed by weathering of nepheline syenite at Passa Quatro, Minas Gerais State, Brazil, bauxites on the hill-tops directly develop from the syenite bed-rock, while downslope, a kaolinitic layer occurs between bauxite and syenite. A petrological investigation was performed on undisturbed weathered rock samples collected from a representative upslope pit. The undisturbed weathered rocks were chemically analysed for major and trace elements including REE and Zr. Mass balance calculations were applied, and the behaviour of the REE in the Passa Quatro weathering system was established compared to REE reference chondrite and to REE reference parent rock. In the lateritic bauxite, the results suggest that the first stages of weathering induce a volumetric change of 50%, i.e. collapse, with respect to the parent rock, and remove REE with a slightly larger loss of the LREE, except Ce, compared to the HREE. In the upper layers, where bauxite is more mature, a net mass gain in REE is observed relative to the underlying layers. This gain takes place during the reduction of the upper layer during the downward progression of the weathering front.
    [Show full text]
  • Rhyolite and Trachyte Formation at Lake City Caldera: Insight from Quantitative Textural and Geochemical Analyses
    Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Reports 2016 Rhyolite and Trachyte Formation at Lake City Caldera: Insight from Quantitative Textural and Geochemical Analyses Jordan Lubbers Michigan Technological University, [email protected] Copyright 2016 Jordan Lubbers Recommended Citation Lubbers, Jordan, "Rhyolite and Trachyte Formation at Lake City Caldera: Insight from Quantitative Textural and Geochemical Analyses", Open Access Master's Thesis, Michigan Technological University, 2016. https://doi.org/10.37099/mtu.dc.etdr/99 Follow this and additional works at: https://digitalcommons.mtu.edu/etdr Part of the Geochemistry Commons, and the Geology Commons RHYOLITE AND TRACHYTE FORMATION AT LAKE CITY CALDERA: INSIGHT FROM QUANTITATIVE TEXTURAL AND GEOCHEMICAL ANALYSES By Jordan E. Lubbers A THESIS Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE In Geology MICHIGAN TECHNOLOGICAL UNIVERSITY 2016 © 2016 Jordan E. Lubbers This thesis has been approved in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE in Geology. Geological and Mining Engineering and Sciences ThesisDepartment Advisor: ofChad Deering Committee Member: Olivier Bachmann Committee Member: William Rose Department Chair: John Gierke Table of Contents Acknowledgements ................................................................................................................................................. 6 Abstract ......................................................................................................................................................................
    [Show full text]