The Origin of Formation of the Amphibolite- Granulite Transition
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The Surface Reactions of Silicate Minerals
RESEARCH BULLETIN 614 SEPTEMBER, 1956 UNIVERSITY OF MISSOURI COLLEGE OF AGRICULTURE AGRICULTURAL EXPERIMENT STATION J. H. Longwell, Director The Surface Reactions Of Silicate Minerals PART II. REACTIONS OF FELDSPAR SURFACES WITH SALT SOLUTIONS. V. E. NASH AND C. E. MARSHALL (Publication authorized September 5, 1956) COLUMBIA, MISSOURI TABLE OF CONTENTS Introduction .......... .. 3 The Interaction of Albite with Salt Solutions . .. 4 The Interaction of Anorthite with Salt Solutions ........ .. 7 Relative Effectiveness of Ammonium Chloride and Magnesium Chloride on the Release of Sodium from Albite . .. 9 Surface Interaction of Albite with Salt Solutions in Methanol . .. 13 Experiments on Cationic Fixation ............................... 16 Detailed Exchange and Activity Studies with Individual Feldspars .......... .. 19 Procedure .. .. 20 Microcline . .. 21 Albite .................................................... 22 Oligoclase . .. 23 Andesine . .. 24 Labradori te . .. 25 Bytownite ................................................. 25 Anorthite . .. 27 Discussion ........ .. 28 Summary ..................................................... 35 References .. .. 36 Most of the experimental material of this and the preceding Research Bulletin is taken from the Ph.D. Thesis of Victor Nash, University of Missouri, June 1955. The experiments on cation fixation were carried our with the aid of a research grant from the Potash Rock Company of America, Lithonia, Georgia, for which the authors wish to record their appreciation. The work was part of Department of Soils Research Project No.6, entitled, "Heavy Clays." The Surface Reactions of Silicate Minerals PART II. REACTIONS OF FELDSPAR SURFACES WITH SALT SOLUTIONS. v. E. NASH AND C. E. MARSHALL INTRODUCTION The review of literature cited in Part I of this series indicates that little is known of the interaction of feldspar surfaces with salt solutions. The work of Breazeale and Magistad (1) clearly demonstrated that ex change reactions between potassium and calcium occur in the case of or thoclase surfaces. -
The Diversity of Magmatism at a Convergent Plate
1 Flow of partially molten crust controlling construction, growth and collapse of the Variscan orogenic belt: 2 the geologic record of the French Massif Central 3 4 Vanderhaeghe Olivier1, Laurent Oscar1,2, Gardien Véronique3, Moyen Jean-François4, Gébelin Aude5, Chelle- 5 Michou Cyril2, Couzinié Simon4,6, Villaros Arnaud7,8, Bellanger Mathieu9. 6 1. GET, UPS, CNRS, IRD, 14 avenue E. Belin, F-31400 Toulouse, France 7 2. ETH Zürich, Institute for Geochemistry and Petrology, Clausiusstrasse 25, CH-8038 Zürich, Switzerland 8 3. Université Lyon 1, ENS de Lyon, CNRS, UMR 5276 LGL-TPE, F-69622, Villeurbanne, France 9 4. Université de Lyon, Laboratoire Magmas et Volcans, UJM-UCA-CNRS-IRD, 23 rue Dr. Paul Michelon, 10 42023 Saint Etienne 11 5. School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth,UK 12 6. CRPG, Université de Lorraine, CNRS, UMR7358, 15 rue Notre Dame des Pauvres, F-54501 13 Vandoeuvre-lès-Nancy, France 14 7. Univ d’Orléans, ISTO, UMR 7327, 45071, Orléans, France ; CNRS, ISTO, UMR 7327, 45071 Orléans, 15 France ; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France 16 8. University of Stellenbosch, Department of Earth Sciences, 7602 Matieland, South Africa 17 9. TLS Geothermics, 91 chemin de Gabardie 31200 Toulouse. 18 19 [email protected] 20 +33(0)5 61 33 47 34 21 22 Key words: 23 Variscan belt; French Massif Central; Flow of partially molten crust; Orogenic magmatism; Orogenic plateau; 24 Gravitational collapse. 25 26 Abstract 27 We present here a tectonic-geodynamic model for the generation and flow of partially molten rocks and for 28 magmatism during the Variscan orogenic evolution from the Silurian to the late Carboniferous based on a synthesis 29 of geological data from the French Massif Central. -
Fluid Inclusions Confirm Authenticity of Tibetan Andesine Date
GEMOLOGY Fluid Inclusions Confirm Authenticity of Tibetan Andesine Can Tibetan andesine now be certified? By Adolf Peretti1, Willy Bieri1, Kathrin Hametner2 and Detlef Günther2 with Richard W. Hughes and Ahmadjan Abduriyim Introduction Untreated copper-bearing feldspar of a rich red color is found in nature, but gem-quality pieces are scarce. For decades the major occurrence has been in Oregon (USA), but gem-quality red feld- spar also occurs in Japan (Furuya & Milisenda, 2009) and elsewhere. Beginning in 2002, gem-quality red plagioclase feldspar en- tered world gem markets. The source was originally stated as the Congo and later morphed into Tibet. By 2007, suspicions that such stones were the result of a treatment were widespread. These suspicions were confirmed in early 2008 (Furuya, 2008), when the treatment was revealed as one of copper diffusion into otherwise lightly-colored plagioclase. This was confirmed by laboratory experiments which replicated the treatment (Emmett & Douthit, 2009). Still, the question remained. Was there a genuine red feldspar mine in Tibet? If so, how would one separate such stones from the treated material? This question challenged the gemological community, resulting in several expeditions to the alleged Tibet- an localities for sample collection and subsequent testing. Figure 2. Copper-bearing red collected by Abduriyim from Yu Lin Gu and view into the valley. (Photos: Ahmadjan Abduriyim) The first of these forays was in 2008 to Bainang, southeast of Shigatse. A group led by Ahmadjan Abduriyim collected numer- ous samples and found the deposit to be credible. However, two subsequent visits (to two widely separated deposits, one of which was adjacent to Bainang) suggested copper-bearing an- desine occurrences in Tibet were being “salted” (Fontaine et al., 2010; Wang et al., 2010). -
Facies and Mafic
Metamorphic Facies and Metamorphosed Mafic Rocks l V.M. Goldschmidt (1911, 1912a), contact Metamorphic Facies and metamorphosed pelitic, calcareous, and Metamorphosed Mafic Rocks psammitic hornfelses in the Oslo region l Relatively simple mineral assemblages Reading: Winter Chapter 25. (< 6 major minerals) in the inner zones of the aureoles around granitoid intrusives l Equilibrium mineral assemblage related to Xbulk Metamorphic Facies Metamorphic Facies l Pentii Eskola (1914, 1915) Orijärvi, S. l Certain mineral pairs (e.g. anorthite + hypersthene) Finland were consistently present in rocks of appropriate l Rocks with K-feldspar + cordierite at Oslo composition, whereas the compositionally contained the compositionally equivalent pair equivalent pair (diopside + andalusite) was not biotite + muscovite at Orijärvi l If two alternative assemblages are X-equivalent, l Eskola: difference must reflect differing we must be able to relate them by a reaction physical conditions l In this case the reaction is simple: l Finnish rocks (more hydrous and lower MgSiO3 + CaAl2Si2O8 = CaMgSi2O6 + Al2SiO5 volume assemblage) equilibrated at lower En An Di Als temperatures and higher pressures than the Norwegian ones Metamorphic Facies Metamorphic Facies Oslo: Ksp + Cord l Eskola (1915) developed the concept of Orijärvi: Bi + Mu metamorphic facies: Reaction: “In any rock or metamorphic formation which has 2 KMg3AlSi 3O10(OH)2 + 6 KAl2AlSi 3O10(OH)2 + 15 SiO2 arrived at a chemical equilibrium through Bt Ms Qtz metamorphism at constant temperature and = -
Mineralogy and Origin of the Titanium
MINERALOGY AND ORIGIN OF THE TITANIUM DEPOSIT AT PLUMA HIDALGO, OAXACA, MEXICO by EDWIN G. PAULSON S. B., Massachusetts Institute of Technology (1961) SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY May 18, 1962 Signature of At r . Depardnent of loggand Geophysics, May 18, 1962 Certified by Thesis Supervisor Ab Accepted by ...... Chairman, Departmental Committee on Graduate Students M Abstract Mineralogy and Origin of the Titanium Deposit at Pluma Hidalgo, Oaxaca, Mexico by Edwin G. Paulson "Submitted to the Department of Geology and Geophysics on May 18, 1962 in partial fulfillment of the requirements for the degree of Master of Science." The Pluma Hidalgo titanium deposits are located in the southern part of the State of Oaxaca, Mexico, in an area noted for its rugged terrain, dense vegetation and high rainfall. Little is known of the general and structural geology of the region. The country rocks in the area are a series of gneisses containing quartz, feldspar, and ferromagnesians as the dominant minerals. These gneisses bear some resemblance to granulites as described in the literature. Titanium minerals, ilmenite and rutile, occur as disseminated crystals in the country rock, which seems to grade into more massive and large replacement bodies, in places controlled by faulting and fracturing. Propylitization is the main type of alteration. The mineralogy of the area is considered in some detail. It is remarkably similar to that found at the Nelson County, Virginia, titanium deposits. The main minerals are oligoclase - andesine antiperthite, oligoclase- andesine, microcline, quartz, augite, amphibole, chlorite, sericite, clinozoi- site, ilmenite, rutile, and apatite. -
Ab Initio Calculations of Elastic Constants of Plagioclase Feldspars
UC Berkeley UC Berkeley Previously Published Works Title Ab initio calculations of elastic constants of plagioclase feldspars Permalink https://escholarship.org/uc/item/9fg3d711 Journal American Mineralogist, 99(11-12) ISSN 0003-004X Authors Kaercher, P Militzer, B Wenk, HR Publication Date 2014-11-01 DOI 10.2138/am-2014-4796 Peer reviewed eScholarship.org Powered by the California Digital Library University of California American Mineralogist, Volume 99, pages 2344–2352, 2014 Ab initio calculations of elastic constants of plagioclase feldspars PAMELA KAERCHER1,*, BURKHARD MILITZER1,2 AND HANS-RUDOLF WENK1 1Department of Earth and Planetary Science, University of California, Berkeley, California 94720, U.S.A. 2Department of Astronomy, University of California, Berkeley, California 94720, U.S.A. ABSTRACT Plagioclase feldspars comprise a large portion of the Earth’s crust and are very anisotropic, mak- ing accurate knowledge of their elastic properties important for understanding the crust’s anisotropic seismic signature. However, except for albite, existing elastic constants for plagioclase feldspars are derived from measurements that cannot resolve the triclinic symmetry. We calculate elastic constants for plagioclase end-members albite NaAlSi3O8 and anorthite CaAl2Si2O8 and intermediate andesine/ labradorite NaCaAl3Si5O16 using density functional theory to compare with and improve existing elastic constants and to study trends in elasticity with changing composition. We obtain elastic con- stants similar to measured elastic constants and find that anisotropy decreases with anorthite content. Keywords: Plagioclase feldspars, elastic constants, ab initio calculations, seismic anisotropy INTRODUCTION and taken into account. Plagioclase feldspars are one of the most important rock- Further uncertainty is introduced when elastic constants are forming minerals, comprising roughly 40% of the Earth’s crust. -
Streaming of Saline Fluids Through Archean Crust
Lithos 346–347 (2019) 105157 Contents lists available at ScienceDirect Lithos journal homepage: www.elsevier.com/locate/lithos Streaming of saline fluids through Archean crust: Another view of charnockite-granite relations in southern India Robert C. Newton a,⁎, Leonid Ya. Aranovich b, Jacques L.R. Touret c a Dept. of Earth, Planetary and Spaces, University of California at Los Angeles, Los Angeles, CA 90095, USA b Inst. of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Science, Moscow RU-119017, Russia c 121 rue de la Réunion, F-75020 Paris, France article info abstract Article history: The complementary roles of granites and rocks of the granulite facies have long been a key issue in models of the Received 27 June 2019 evolution of the continental crust. “Dehydration melting”,orfluid-absent melting of a lower crust containing H2O Received in revised form 25 July 2019 only in the small amounts present in biotite and amphibole, has raised problems of excessively high tempera- Accepted 26 July 2019 tures and restricted amounts of granite production, factors seemingly incapable of explaining voluminous bodies Available online 29 July 2019 of granite like the Archean Closepet Granite of South India. The existence of incipient granulite-facies metamor- phism (charnockite formation) and closely associated migmatization (melting) in 2.5 Ga-old gneisses in a quarry Keywords: fl Charnockite exposure in southern India and elsewhere, with structural, chemical and mineral-inclusion evidence of uid ac- Granite tion, has encouraged a wetter approach, in consideration of aqueous fluids for rock melting which maintain suf- Saline fluids ficiently low H2O activity for granulite-facies metamorphism. -
An Investigation Into the UV Fluorescence of Feldspar Group
An Investigation into UV Fluorescence in Feldspar Group Minerals Natasha Morrison Submitted in Partial Fulfillment of the Requirement for the Degree of Honours Bachelor of Science, Department of Earth Sciences At Dalhousie University Halifax, Nova Scotia March 17th, 2013 Submitted to: Dr. Richard Cox Dr. Martin Gibling 1 Distribution License DalSpace requires agreement to this non-exclusive distribution license before your item can appear on DalSpace. NON-EXCLUSIVE DISTRIBUTION LICENSE You (the author(s) or copyright owner) grant to Dalhousie University the non-exclusive right to reproduce and distribute your submission worldwide in any medium. You agree that Dalhousie University may, without changing the content, reformat the submission for the purpose of preservation. You also agree that Dalhousie University may keep more than one copy of this submission for purposes of security, back-up and preservation. You agree that the submission is your original work, and that you have the right to grant the rights contained in this license. You also agree that your submission does not, to the best of your knowledge, infringe upon anyone's copyright. If the submission contains material for which you do not hold copyright, you agree that you have obtained the unrestricted permission of the copyright owner to grant Dalhousie University the rights required by this license, and that such third-party owned material is clearly identified and acknowledged within the text or content of the submission. If the submission is based upon work that has been sponsored or supported by an agency or organization other than Dalhousie University, you assert that you have fulfilled any right of review or other obligations required by such contract or agreement. -
Optical Properties of Common Rock-Forming Minerals
AppendixA __________ Optical Properties of Common Rock-Forming Minerals 325 Optical Properties of Common Rock-Forming Minerals J. B. Lyons, S. A. Morse, and R. E. Stoiber Distinguishing Characteristics Chemical XI. System and Indices Birefringence "Characteristically parallel, but Mineral Composition Best Cleavage Sign,2V and Relief and Color see Fig. 13-3. A. High Positive Relief Zircon ZrSiO. Tet. (+) 111=1.940 High biref. Small euhedral grains show (.055) parallel" extinction; may cause pleochroic haloes if enclosed in other minerals Sphene CaTiSiOs Mon. (110) (+) 30-50 13=1.895 High biref. Wedge-shaped grains; may (Titanite) to 1.935 (0.108-.135) show (110) cleavage or (100) Often or (221) parting; ZI\c=51 0; brownish in very high relief; r>v extreme. color CtJI\) 0) Gamet AsB2(SiO.la where Iso. High Grandite often Very pale pink commonest A = R2+ and B = RS + 1.7-1.9 weakly color; inclusions common. birefracting. Indices vary widely with composition. Crystals often euhedraL Uvarovite green, very rare. Staurolite H2FeAI.Si2O'2 Orth. (010) (+) 2V = 87 13=1.750 Low biref. Pleochroic colorless to golden (approximately) (.012) yellow; one good cleavage; twins cruciform or oblique; metamorphic. Olivine Series Mg2SiO. Orth. (+) 2V=85 13=1.651 High biref. Colorless (Fo) to yellow or pale to to (.035) brown (Fa); high relief. Fe2SiO. Orth. (-) 2V=47 13=1.865 High biref. Shagreen (mottled) surface; (.051) often cracked and altered to %II - serpentine. Poor (010) and (100) cleavages. Extinction par- ~ ~ alleL" l~4~ Tourmaline Na(Mg,Fe,Mn,Li,Alk Hex. (-) 111=1.636 Mod. biref. -
Nature and Origin of Fluids in Granulite Facies Metamorphism R.C
129 NATURE AND ORIGIN OF FLUIDS IN GRANULITE FACIES METAMORPHISM R.C. Newton, Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, USA Orthopyroxene, the definitive mineral of the granulite facies, may originate in prograde dehydration reactions in rock systems open to fluids or may be a premetamorphic relic of igneous intrusions or their contact aureoles which persisted through fluid-deficient metamorphism. Terrains showing evidence of open-system orthopyroxene-forming reactions are those of South India and southern Norway. An example of fluid-deficient granulite facies metamorphism is the Adirondack Highlands of New York, where metamorphic pyroxene commonly resulted from dry recrystallization of pyroxenes of plutonic charnockites and anorthosites. The metamorphism recorded by the presence of orthopyroxene in different terrains may thus have been conservative or may have involved fluids of different origins pervasive on various length-scales. Metamorphism with pervasive metasomatism is signaled by monotonous H20, C02 and 02 fugacities over large areas, nearly independent of lithology, by scarcity of relict textures, and by pronounced depletion of Rb and other large ion lithophile (LILE) elements in the highest grade areas, such as the southernmost part of the Bamble, South Norway, terrain (1). Primary hornblende is rare or absent in quartzofeldspathic gneisses and orthopyroxene is ubiquitous in acid and basic rocks in the charnockitic terrains. Pronounced major and minor element redistributions took place -
Towards a Unified Nomenclature in Metamorphic Petrology
8. Amphibolite and Granulite Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: Web version 01.02.07 1José Coutinho, 2Hans Kräutner, 3Francesco Sassi, 4Rolf Schmid and 5Sisir Sen. 1 J. Coutinho, University of São Paulo, São Paulo, Brazil 2 L M University, Munich, Germany 3 F. Sassi, Department of Mineralogy and Petrography, University of Padova, Italy 4 R. Schmid, ETH-Centre, Zürich, Switzerland 5 S. Sen, Indian Institute of Technology, Kharagpur, India Introduction This paper summarises the results of the discussions by the SCMR, and the response to circulars distributed by the SCMR, which demonstrated the highly variable usage of the terms granulite and amphibolite. It presents those definitions which currently seem to be the most appropriate ones. Some notes are included in order to explain the reasoning behind the suggested definitions. In considering the definitions it is important to remember that some of them are a compromise of highly different, even conflicting, opinions and traditions. The names amphibolite and granulite have been used in geological literature for nearly 200 years: amphibolite since Brongniart (1813), granulite since Weiss (1803). Although Brongniart described amphibolite as a rock composed of amphibole and plagioclase, in those early days the meaning of the term was variable. Only later (e.g. Rosenbusch, 1898) was it fixed as metamorphic rock consisting of hornblende and plagioclase, and of medium to high metamorphic grade. In contrast, the use of the name granulite was highly variable, a position which was further complicated by the introduction of the facies principle (Eskola, 1920, 1952) when the name granulite was proposed for all rocks of the granulite facies. -
Oregon Geologic Digital Compilation Rules for Lithology Merge Information Entry
State of Oregon Department of Geology and Mineral Industries Vicki S. McConnell, State Geologist OREGON GEOLOGIC DIGITAL COMPILATION RULES FOR LITHOLOGY MERGE INFORMATION ENTRY G E O L O G Y F A N O D T N M I E N M E T R R A A L P I E N D D U N S O T G R E I R E S O 1937 2006 Revisions: Feburary 2, 2005 January 1, 2006 NOTICE The Oregon Department of Geology and Mineral Industries is publishing this paper because the infor- mation furthers the mission of the Department. To facilitate timely distribution of the information, this report is published as received from the authors and has not been edited to our usual standards. Oregon Department of Geology and Mineral Industries Oregon Geologic Digital Compilation Published in conformance with ORS 516.030 For copies of this publication or other information about Oregon’s geology and natural resources, contact: Nature of the Northwest Information Center 800 NE Oregon Street #5 Portland, Oregon 97232 (971) 673-1555 http://www.naturenw.org Oregon Department of Geology and Mineral Industries - Oregon Geologic Digital Compilation i RULES FOR LITHOLOGY MERGE INFORMATION ENTRY The lithology merge unit contains 5 parts, separated by periods: Major characteristic.Lithology.Layering.Crystals/Grains.Engineering Lithology Merge Unit label (Lith_Mrg_U field in GIS polygon file): major_characteristic.LITHOLOGY.Layering.Crystals/Grains.Engineering major characteristic - lower case, places the unit into a general category .LITHOLOGY - in upper case, generally the compositional/common chemical lithologic name(s)