Occurrence, Texture, and Classification of Igneous Rocks - Gezahegn Yirgu
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Syllabus of Geology
THE UNIVERSITY OF BURDWAN Syllabus for 3-Year Degree Course in Geology (Honours) Full Marks: 800 Distribution of Papers, Marks And Lectures/Periods PART I EXAMINATION (EXAMINATION AT THE END OF FIRST YEAR) Theory Subject Marks No. of lectures Paper-I A. Crystallogroaphy (10) & Mineralogy (30) 40 80 B. Igneus Petrology- I 20 40 C. Metamorphic Petrology-I 20 40 D. Sedimentology-I 20 40 TOTAL 100 Paper-II A. Earth System Sciences 20 40 B. Structural Geology-I 20 40 C. Principles of Stratigraphy 10 20 TOTAL 50 Practical Paper-I Crystallography 05 Hand specimens of minerals 10 Hand specimens of rocks 15 Identification of minerals under microscope 10 Field Report 05 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 200 PART II EXAMINATION (EXAMINATION AT THE END OF SECOND YEAR) Theory Subject Marks No. of lectures Paper-III A. Igneous Petrology-II 20 40 B. Metamorphic Petrology-II 20 40 C. Geochemistry 30 60 D. Geotectonics 30 60 TOTAL 100 Paper-IV A. Structural Geology-II 20 40 B. Sedimentology-II 20 40 C. Hydrogeology 10 20 TOTAL 50 Practical Paper-II Structural Geology-I 35 Field Report 10 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 200 1 PART III EXAMINATION (EXAMINATION AT THE END OF THIRD YEAR) Theory Subject Marks No. of lectures Paper-V A. Principles of Palaeonotology 20 40 B. Palaeonotology 30 60 C. Indian Stratigraphy 50 100 TOTAL 100 Paper-VI A. Economic Geology 50 100 B. Fuels 20 40 C. Natural Resources Management 30 60 TOTAL 100 Practical Paper-III Petrography of Igneous rocks 15 Petrography of Metamorphic rocks 15 Special optics 15 Laboratory Note Book 05 TOTAL 50 150 Paper-IV Sedimentology 15 Remote Sensing 15 Hydrogeology 15 Laboratory Note Book 05 TOTAL 50 150 Paper-V Structural Geology-II 35 Field Report 10 Laboratory Note Book 05 TOTAL 50 150 Paper-VI Palaeonotology 45 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 400 2 DETAILS OF THE THREE YEAR B.Sc. -
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 -
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. -
Chapter 2 Alaska’S Igneous Rocks
Chapter 2 Alaska’s Igneous Rocks Resources • Alaska Department of Natural Resources, 2010, Division of Geological and Geophysical Surveys, Alaska Geologic Materials Center website, accessed May 27, 2010, at http://www.dggs.dnr.state.ak.us/?link=gmc_overview&menu_link=gmc. • Alaska Resource Education: Alaska Resource Education website, accessed February 22, 2011, at http://www.akresource.org/. • Barton, K.E., Howell, D.G., and Vigil, J.F., 2003, The North America tapestry of time and terrain: U.S. Geological Survey Geologic Investigations Series I-2781, 1 sheet. (Also available at http://pubs.usgs.gov/imap/i2781/.) • Danaher, Hugh, 2006, Mineral identification project website, accessed May 27, 2010, at http://www.fremontica.com/minerals/. • Digital Library for Earth System Education, [n.d.], Find a resource—Bowens reaction series: Digital Library for Earth System Education website, accessed June 10, 2010, at http://www.dlese.org/library/query.do?q=Bowens%20reaction%20series&s=0. • Edwards, L.E., and Pojeta, J., Jr., 1997, Fossils, rocks, and time: U.S. Geological Survey website. (Available at http://pubs.usgs.gov/gip/fossils/contents.html.) • Garden Buildings Direct, 2010, Rocks and minerals: Garden Buildings Direct website, accessed June 4, 2010, at http://www.gardenbuildingsdirect.co.uk/Article/rocks-and- minerals. • Illinois State Museum, 2003, Geology online–GeoGallery: Illinois State Museum Society database, accessed May 27, 2010 at http://geologyonline.museum.state.il.us/geogallery/. • Knecht, Elizebeth, designer, Pearson, R.W., and Hermans, Majorie, eds., 1998, Alaska in maps—A thematic atlas: Alaska Geographic Society, 100 p. Lillie, R.J., 2005, Parks and plates—The geology of our National parks, monuments, and seashores: New York, W.W. -
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. -
Mineral Mania
The Rock Factory A Pre-Visit Information Guide for Teachers Meets Next Generation Science Standards: 5-PS1-3; MS LS4-1,2; MS ESS1-4; MS-ESS2-1 How does our Earth create so many different types of rocks? Learn about the different processes that form and reform rocks as you identify many types of rocks, minerals and fossils. Students will learn to think like geologists as they move through interactive investigation stations packed with specimens from the Museum’s collections. OBJECTIVES The Rock Cycle: Students will examine the three types of rocks - igneous, metamorphic and sedimentary – and discover the processes that create them. Tracing the connections between shale and slate, limestone and marble, students will discover how the rock cycle changes the very ground beneath our feet! Characteristics of Rocks Students will learn how to observe and identify rocks through their unique characteristics, looking for telling clues such as layering, crystal size, fossils, magnetism, and more. Students will practice their observational skills as they describe the Museum’s unique rock and mineral specimens. Investigation Stations: Students will explore Museum geology specimens up close at investigation stations to answer such questions as: “Why do fossils form only in certain rocks?” “How do rocks form from volcanic eruptions?” “How can I recognize different types of rocks?”. ACTIVITIES Teachers are encouraged to conduct pre-visit and post-visit classroom discussions and activities with their classes to make the most of their experience. Encourage your students to start a classroom rock collection, and create an exhibit with the rocks organized by type – igneous, sedimentary and metamorphic. -
Geologic Boulder Map of Campus Has Been Created As an Educational Educational an As Created Been Has Campus of Map Boulder Geologic The
Adam Larsen, Kevin Ansdell and Tim Prokopiuk Tim and Ansdell Kevin Larsen, Adam What is Geology? Igneous Geo-walk ing of marine creatures when the limestone was deposited. It also contains by edited and Written Geology is the study of the Earth, from the highest mountains to the core of The root of “igneous” is from the Latin word ignis meaning fire. Outlined in red, numerous fossils including gastropods, brachiopods, receptaculita and rugose the planet, and has traditionally been divided into physical geology and his- this path takes you across campus looking at these ancient “fire” rocks, some coral. The best example of these are in the Geology Building where the stone torical geology. Physical geology concentrates on the materials that compose of which may have been formed at great depths in the Earth’s crust. Created was hand-picked for its fossil display. Campus of the Earth and the natural processes that take place within the earth to shape by the cooling of magma or lava, they can widely vary in both grain size and Granite is another common building stone used on campus. When compa- its surface. Historical geology focuses on Earth history from its fiery begin- mineral composition. This walk stops at examples showing this variety to help nies sell granite, they do not use the same classification system as geologists. nings to the present. Geology also explores the interactions between the you understand what the change in circumstances will do to the appearance Granite is sold in many different colours and mineral compositions that a Map Boulder Geologic lithosphere (the solid Earth), the atmosphere, the biosphere (plants, animals of the rock. -
Chapter 1 – Introduction – Review of Rocks and Plate Tectonics Practice Exam and Study Guide
Chapter 1 – Introduction – Review of Rocks and Plate Tectonics Practice Exam and Study Guide To be able to understand the material covered during this course you need to have a basic background in the kinds of rocks making up our planet. This section of the study guide is aimed at helping you gain that background. 1. What are the three major groups of rocks found on planet Earth? Igneous Rocks 2. Which of the following processes is associated with igneous rocks? a. Solid‐state recrystallization b. Weathering and erosion c. Transportation and deposition d. Cooling a silicate liquid to a solid rock e. The accumulation of granitic debris in a moraine 3. If a silicate liquid flows out along the Earth’s surface or seabed, then it is called _______________. 4. If a silicate liquid exists beneath the Earth’s surface or seabed, then it is called _______________. 5. Which of the following terms refer to a body of magma or its solidified equivalent? a. Basalt b. Sandstone c. Gneiss d. Pluton e. Schist 6. If you can see the crystals making up an igneous rock with the naked eye, then the texture is described as a. Pyroclastic b. Phaneritic c. Aphanitic d. Porphyritic e. Aphyric from Perilous Earth: Understanding Processes Behind Natural Disasters, ver. 1.0, June, 2009 by G.H. Girty, Department of Geological Sciences, San Diego State University Page 1 7. In an aphanitic igneous rock can you make out the outlines of individual crystals with the naked eye? Yes or No 8. What type of igneous rock is the most volumetrically important on our planet? Intrusive Igneous Rocks 9. -
Earth Sciences 3313A: IGNEOUS PETROLOGY ˗ Fall 2019
EARTH SCIENCES 3313A – Igneous Petrology Earth Sciences 3313A: IGNEOUS PETROLOGY ˗ Fall 2019 Arenal Volcano, Costa Rica Ultramafic flow, spinifex texture, fresh and altered Instructor: Robert Linnen Office B&GS 1000B email: [email protected] tel. ext. 89207 Meeting hours: There are no fixed office hours, please set up an appointment when you need to meet Teaching Assistant: to be determined Pre-requisites: ES 2206a/b - Mineral Systems, Crystallography and Optics Schedule Lectures: Tuesdays & Thursdays: 12:30-13:20, Room: NCB-295. Labs: Thursday 2:30-5:20 and, depending on enrolment, 6:00-9:00 Room: B&GS-1065 Important Dates Tuesday, October 17th: Midterm exam in class Fall Reading Week November 4-8 no classes Thursday, November 28: Lab exam in BGS 1065 December 8 – 19: Examination period. Final exam, date and location TBA. 1 EARTH SCIENCES 3313A – Igneous Petrology CALENDAR DESCRIPTION OF EARTH SCIENCES 3313A “IGNEOUS PETROLOGY" Study of igneous processes using rock and thin section descriptions (petrography). Discussion of how different compositions and conditions influence the phases present in a rock (phase equilibria). Association of different rock types with plate tectonic setting. WHAT ARE THE PRINCIPLE OBJECTIVES OF THIS COURSE? To outline the physical and chemical properties of magma, to introduce the techniques that are used to interpret the origin and evolution of different series of magmas and to examine in more detail magma evolution in specific igneous/tectonic environments. The laboratory is an integral part of the course and students will learn to identify common igneous rocks and textures in hand specimen and in thin section using a petrographic microscope. -
Rocks and Geology: General Information
Rocks and Geology: General Information Rocks are the foundation of the earth. Rock provides the firmament beneath our oceans and seas and it covers 28% of the earth's surface that we all call home. When we travel any distance in any given direction, it is impossible not to see the tremendous variety in color, texture, and shape of the rocks around us. Rocks are composed of one or more minerals. Limestone, for example, is composed primarily of the mineral calcite. Granite can be made up of the minerals quartz, orthoclase and plagioclase feldspars, hornblende, and biotite mica. Rocks are classified by their mineral composition as well as the environment in which they were formed. There are three major classifications of rocks: igneous, sedimentary and metamorphic. A question: Which kind of rock came first? Think about it....... The following sections describe the conditions and processes that create the landscape we admire and live on here on "terra firma." IGNEOUS ROCKS The millions of tons of molten rock that poured out of the volcano Paracutin in Mexico, and from the eruption of Mount St. Helens in Washington State illustrate one of the methods of igneous rock formation. Igneous (from fire) rocks are formed when bodies of hot liquid rock called magma located beneath the earth's crust, find their way upward through the crust by way of fissures or faults. If the magma reaches the earth's surface, it forms extrusive igneous rocks or volcanic rocks. If the magma cools before it reaches the surface, it forms bodies of rock called intrusive igneous rocks or plutonic rocks. -
A) Diorite B) Gabbro C) Andesite D) Pumice 1. the Photograph Below
1. The photograph below shows an igneous rock with 4. The photograph below shows the intergrown crystals mineral crystals ranging in size from 2 to 6 of a pegmatite rock. millimeters. The rock is composed of 58% plagioclase feldspar, 26% amphibole, and 16% biotite. What is the name of this rock? A) diorite B) gabbro Which characteristic provides the best evidence that this pegmatite solidified deep underground? C) andesite D) pumice 2. Which igneous rock is dark colored, cooled rapidly on A) low density Earth's surface, and is composed mainly of B) light color plagioclase feldspar, olivine, and pyroxene? C) felsic composition D) very coarse texture A) obsidian B) rhyolite C) gabbro D) scoria 3. Which intrusive igneous rock could be composed of approximately 60% pyroxene, 25% plagioclase feldspar, 10% olivine, and 5% amphibole? A) granite B) rhyolite C) gabbro D) basalt 5. The graph below shows the relationship between the cooling time of magma and the size of the crystals produced. Which graph correctly shows the relative positions of the igneous rocks granite, rhyolite, and pumice? A) B) C) D) 6. The diagrams below show the crystals of four different rocks viewed through the same hand lens. Which crystals most likely formed from molten material that cooled and solidified most rapidly? A) B) C) D) 7. "Which granite sample most likely formed from magma that cooled and solidified at the slowest rate?" A) " " B) " " C) " " D) " " Base your answers to questions 8 and 9 on the diagram below and on your knowledge of Earth science. The diagram represents a portion of the scheme for igneous rock identification. -
Attributes of Skaergaard-Type PGE Reefs
Attributes of Skaergaard-Type PGE Reefs James D. Miller, Jr.1 and Jens C. Ø. Andersen2 1Minnesota Geological Survey, c/o NRRI, University of Minnesota-Duluth, 5013 Miller Trunk Hwy., Duluth, MN, 55811 , USA 2Camborne School of Mines, University of Exeter, Redruth, Cornwall, TR15 3SE UK e-mail: [email protected], [email protected] Stratiform, platinum group element (PGE) peridotite, pyroxenite, and dunite are usually deposits have long been known to occur in quantitatively minor. When well-differentiated, ultramafic-mafic intrusive complexes such as such intrusions display a simplified cumulus Bushveld and Stillwater (Naldrett, 1989b). stratigraphy following the scheme: Ol or Pl only-> Commonly known as PGE reefs, such deposits are Ol + Pl -> Pl + Cpx + FeOx ± Ol -> Pl + Cpx + typically found near the transition from ultramafic FeOx + Ol + Ap. They have a strong cryptic to mafic cumulates where they occur as 1-3 meter layering towards iron-enrichment indicative of thick intervals enriched in PGEs (1-20 ppm) and Fenner-type differentiation. They differ from trace to moderate amounts of sulfide (0.5-5 wt %). classic PGE reef-bearing intrusions by lacking a However, relatively recent discoveries have significant ultramafic component (early olivine- demonstrated that potentially economic stratiform only crystallization is minor to absent in most PGE mineralization may also occur in tholeiitic tholeiitic intrusions) and by being poor in mafic layered intrusions. Au- and PGE-bearing orthopyroxene (inverted pigeonite is rarely a layers