Preparation of Thin Sections

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Preparation of Geology Department Thin Sections Thin Section Laboratory Rock samples-typically cores or individual grab samples, require processing before they can be used for mineral analysis by either PLM (Polarizing Light Microscope, Microprobe and Scanning Electron Microscope/X-ray Microanalysis. The sample has to be thin enough for light to pass through in a light microscope and have a polished surface for electron microscope studies. For more information on thin section production contact: Lakehead University Geology Department 955 Oliver Rd Thunder Bay, ON, P7b 5e1 807 343-8677 Synite-Coldwell complex near Marathon STEP 1: CUTTING A SLAB A suitable size slab for mounting on a slide is cut from a piece of rock or drill core with a diamond saw STEP 2: Initial Lapping of the Slab The slab is labelled on one side and the other side is lapped flat and smooth first on a cast iron lap with 400grit carborundum, then finished on a glass plate with 600 grit carborondum STEP 3: Glass Slide is Added After drying on a hot plate, a glass slide is glued to the lapped face of the slab with epoxy. STEP 4: Slab is sectioned Using a thin section saw, the slab is cut-off close to the slide. The thickness is further reduced on a thin section grinder. Powders are mixed with expoxy, then spread on a slide and allowed to cure. The surface is ground flat on the thin section grinder, then finished similarly to a thin sections STEP 5: Final Lapping A finished thickness of 30 microns is achieved by lapping the section by hand on a glass plate with 600 grit carborundum. A fine grinding with 1000 grit prior to polishing is optional. STEP 6: Polishing The section is placed in a holder and spun on a polishing machine using nylon cloth and diamond paste unitil a suitable polish is achieved for microscope or SEM studies, STEP 7: Final inspection Examples of finished thin sections.

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Expedition 369 Thin Sections, Site U1512
Site U1512 core descriptions Thin sections THIN SECTION LABEL ID 369-U1512A-5R-4-W 72/75-TSB-TS1 Thin section no.: 1 Observer: CW Unit/subunit: II-a Thin section summary: A silty clay with moderately developed lamination and rare burrows. The sediment sample is moderately sorted and is comprised of silt-sized angular mineral grains including common quartz and trace amounts of feldspar hosted within a clay-rich matrix. Rare grains are sand sized. Other minerals/bioclasts present in common and trace amounts include muscovite mica, biotite mica, tubular bioclast fragments and poorly developed/fragmented radiolarians. Plane-polarized: 43920161 Cross-polarized: 43920141 Sediments and Sedimentary Rock Complete Lithology Name: silty clay Remarks: GRAIN SIZE Gravel Sand Silt Clay Percent 0 5 25 70 COMPOSITION Siliciclastic Calcareous Biosiliceous Mineral grains (%) 94 5 1 Cement (%) 94 5 1 MINERAL GRAIN ROUNDNESS MINERAL GRAIN SORTING angular moderate Mineral grain Abundance Quartz C Microcline feldspar T Clay D Calcite R D=dominant, A=abundant, C=common, R=rare, T=trace 369-U1512A-5R-4-W 72/75-TSB-TS1 Page 1 of 1 Site U1512 core descriptions Thin sections THIN SECTION LABEL ID 369-U1512A-13R-5-W 26/29-TSB-TS2 Thin section no.: 2 Observer: CW Unit/subunit: II-b Thin section summary: A possible sideritic siltstone, with quartz, glauconite, and Fe-oxide. The rock sample is moderately sorted and is comprised of silt-sized siderite grains hosted within a clay-rich matrix. Silt-sized quartz grains are common throughout. Pore spaces are also comprised of quartz cements. The rock sample is likely reworked from a proximal source area on the slope due to the angularity of the grains.
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Depositional Setting of Algoma-type Banded Iron Formation Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok To cite this version: Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok. Depositional Setting of Algoma-type Banded Iron Formation. Precambrian Research, Elsevier, 2016. hal-02283951 HAL Id: hal-02283951 https://hal-brgm.archives-ouvertes.fr/hal-02283951 Submitted on 11 Sep 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Depositional Setting of Algoma-type Banded Iron Formation B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok PII: S0301-9268(16)30108-5 DOI: http://dx.doi.org/10.1016/j.precamres.2016.04.019 Reference: PRECAM 4501 To appear in: Precambrian Research Received Date: 26 September 2015 Revised Date: 21 January 2016 Accepted Date: 30 April 2016 Please cite this article as: B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok, Depositional Setting of Algoma-type Banded Iron Formation, Precambrian Research (2016), doi: http://dx.doi.org/10.1016/j.precamres. 2016.04.019 This is a PDF file of an unedited manuscript that has been accepted for publication.
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Metamorphism
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Data of Geochemistry
Data of Geochemistry ' * Chapter W. Chemistry of the Iron-rich Sedimentary Rocks GEOLOGICAL SURVEY PROFESSIONAL PAPER 440-W Data of Geochemistry MICHAEL FLEISCHER, Technical Editor Chapter W. Chemistry of the Iron-rich Sedimentary Rocks By HAROLD L. JAMES GEOLOGICAL SURVEY PROFESSIONAL PAPER 440-W Chemical composition and occurrence of iron-bearing minerals of sedimentary rocks, and composition, distribution, and geochemistry of ironstones and iron-formations UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1966 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 45 cents (paper cover) CONTENTS Page Face Abstract. _ _______________________________ Wl Chemistry of iron-rich rocks, etc. Continued Introduction. _________ ___________________ 1 Oxide facies Continued Iron minerals of sedimentary rocks __ ______ 2 Hematitic iron-formation of Precambrian age__ W18 Iron oxides __ _______________________ 2 Magnetite-rich rocks of Mesozoic and Paleozoic Goethite (a-FeO (OH) ) and limonite _ 2 age___________-__-._____________ 19 Lepidocrocite (y-FeO(OH) )________ 3 Magnetite-rich iron-formation of Precambrian Hematite (a-Fe2O3) _ _ _ __ ___. _ _ 3 age._____-__---____--_---_-------------_ 21 Maghemite (7-Fe203) __ __________ 3 Silicate facies_________________________________ 21 Magnetite (Fe3O4) ________ _ ___ 3 Chamositic ironstone____--_-_-__----_-_---_- 21 3 Silicate iron-formation of Precambrian age_____ 22 Iron silicates 4 Glauconitic rocks__-_-____--------__-------- 23 4 Carbonate facies______-_-_-___-------_---------- 23 Greenalite. ________________________________ 6 Sideritic rocks of post-Precambrian age._______ 24 Glauconite____ _____________________________ 6 Sideritic iron-formation of Precambrian age____ 24 Chlorite (excluding chamosite) _______________ 7 Sulfide facies___________________________ 25 Minnesotaite.
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Petrography, Mineralogy, and Reservoir Characteristics of the Upper Cretaceous Mesaverde Group in the East-Central Piceance Basin, Colorado
Petrography, Mineralogy, and Reservoir Characteristics of the Upper Cretaceous Mesaverde Group in the East-Central Piceance Basin, Colorado U.S. GEOLOGICAL SURVEY BULLETIN 1 787-G Chapter G Petrography, Mineralogy, and Reservoir Characteristics of the Upper Cretaceous Mesaverde Group in the East-Central Piceance Basin, Colorado By JANET K. PITMAN, CHARLES W. SPENCER, and RICHARD M. POLLASTRO A multidisciplinary approach to research studies of sedimentary rocks and their constituents and the evolution of sedimentary basins, both ancient and modern U.S. GEOLOGICAL SURVEY BULLETIN 1787 EVOLUTION OF SEDIMENTARY BASINS-UINTA AND PICEANCE BASINS DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U. S. GEOLOGICAL SURVEY Dallas L Peck, Director Any use of trade, product, or firm names in tl is publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. UNITED STATES GOVERNMENT PR NTING OFFICE: 1989 For sale by the Books and Open-File Reports Section U.S. Geological Survey Federal Center Box 25425 Denver, CO 80225 Library of Congress Cataloging-in-Publication Data Pitman, Janet K. Petrography, mineralogy, and reservoir characteristics of the Upper Cretaceous Mesaverde Group in the East-Ce tral Piceance Basin, Colorado / by Janet K. Pitman, Charles W. Spencer, and Richard M. Pollastro. p. cm. (Evolution of sedimentary basins-Uinta and Piceance basins ; ch. G) (U.S. Geological Survey bulletin ; 1787-G) Bibliography: p. Supt. of Docs, no.: I 19.3: 1787-G 1. Geology Colorado Piceance Creek Watershed. 2. Gas, Natural Colorado Piceance Creek Watershed. 3. Mesaverde Group. 4. Geology, Stratigraphic Cretaceous. I. Spencer, Charles Winthrop, 1930- . II.
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Microscopic Study of Common Metamorphic Rocks
EXPERIMENT 10 MICROSCOPIC STUDY OF COMMON METAMORPHIC ROCKS Outline of Experiment____________________________ 10.1 Introduction Gneiss Expected Learning Skills 10.5 Non-foliated Metamorphic 10.2 Requirements Rocks 10.3 Basic Concepts Marble 10.4 Foliated Metamorphic Quartzite Rocks 10.6 Laboratory Exercises Slate 10.7 References Phyllite 10.8 Learning Resources Schist 10.1 INTRODUCTION You have learnt to identify metamorphic rocks in hand specimens in the previous experiment. In this experiment you will learn to identify microscopic characters of metamorphic rocks of foliated metamorphic rocks such as slate, 184 Experiment 9 Megascopic Study of Common Metamorphic Rocks ………………………………………………………………………………………………………………………. phyllite, schist and gneiss and non-foliated metamorphic rocks such as marble and quartzite. Expected Learning Skills__________________________ After performing this experiment, you should be able to: ❖ identify texture and mineral composition of foliated metamorphic rocks such as slate, phyllite, schist and gneiss; ❖ recognise texture and mineral composition of non-foliated metamorphic rocks such as marble and quartzite; and ❖ list the facies and associated protolith of slate, phyllite, schist, gneiss, marble and quartzite. 10.2 REQUIREMENTS To perform this experiment successfully, following are the requirements: • Polarising microscope with light source • Thin sections of slate, phyllite, schist, gneiss, marble and quartzite • Pen, pencil, eraser, scale, sharpener, coloured pencils and drawing compass • Laboratory file • You are instructed to draw the sketch of the hand specimen observed in the laboratory given by your instructor. Instructions: You are required to study Block 3 of BGYCT-135 course (Petrology) before performing this experiment. Bring this practical manual along with Block-3 of BGYCT-133 course while attending the Practical Counselling session.
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Metamorphism of Graphitic Schists from Syros, Greece
Metamorphism of Graphitic Schists from Syros, Greece Roxanne Renedo Submitted to the Department of Geology of Smith College in partial fulfillment of the requirements for the degree of Bachelor of Arts John B. Brady, Honors Project Advisor May 11, 2009 This thesis is dedicated in loving memory to Wallace Buckland Table of Contents List of Figures …….………………………………………………………………………… ii List of Tables ………………………………………………………………………………...iii Abstract ……………………………………………………………………………………… iv Acknowledgements ...…………………………………………………………………………vi Chapter 1: Introduction .………………………………………………………………………1 Geologic Evolution of the Aegean Sea and Syros Lithologies Previous work on the Aegean Sea and Syros Purpose of Study Chapter 2: Field Observations and Methods …………………………………………………13 Field Methods Lithology – Graphitic Schists Methods Chapter 3: Petrography ..……………………………………………………………………..19 Textures Chapter 4: Chemical Analysis ………………………………………………………………..26 Methods Mineral Description and Chemical Compositions Chapter 5: Microprobe Analysis ……………………………………………………………...31 Previously Proposed Reactions Microprobe Images Discussion Chapter 6: ACFN and ACF Diagramming……………………………………………………57 Chapter 7: Geothermobarometry ……………………………………………………………..64 Chapter 8: Summary ………………………………………………………………………….66 References ..…………………………………………………………………………………...70 Appendices ……………………………………………………………………………………72 i List of Figures 1-1: Mediterranean Sea and Aegean Sea map 2 1-2: Slab subduction through time 2 1-3: Events Slide 4 1-4: Map of the Aegean with large-scale active and fossil faults
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Petrography Edward F
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Petrographic Characteristics of Sandstones As a Basis to Evaluate Their Suitability in Construction and Energy Storage Applications
Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 4 February 2020 Peer-reviewed version available at Energies 2020, 13, 1119; doi:10.3390/en13051119 Article Petrographic characteristics of sandstones as a basis to evaluate their suitability in construction and energy storage applications. A case study from Klepa Nafpaktias (Central Western Greece). Petros Petrounias 1,*, Panagiota P. Giannakopoulou 1, Aikaterini Rogkala 1, Maria Kalpogiannaki1, Petros Koutsovitis1, Maria-Elli Damoulianou1, Nikolaos Koukouzas2 1 Section of Earth Materials, Department of Geology, University of Patras, 26504, Patras, Greece; [email protected] (P.P.G.); [email protected] (A.R.); [email protected] (M.K); [email protected] (P.K); [email protected] (M.E.D); 2 Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Greece; [email protected] (N.K) * Correspondence: [email protected] Abstract: This paper examines the influence of the petrographic characteristics of sandstones from Klepa Nafpaktias (Greece) on their suitability in construction (concrete) and energy storage applications. For this scope, ten sandstones were collected in order to study their petrographic characteristics using petrographic microscope and a GIS software as well as their basic physical, mechanical and physicochemical properties. Concrete specimens (C25/30) were produced with constant volume proportions, workability, mixing and curing conditions using different sizes of each aggregate type. Aggregates were mixed both in dry and water saturated states in concrete. Three different types of sandstone aggregates were examined and classified in three district groups according to their physicomechanical properties, petrographic characteristics and surface texture. The classification in groups after the concrete compressive strength test (UCS) verified the initial classification in the same three groups relative to their grain size from coarse to fine grained.
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