DOCSLIB.ORG

Topic B - Geologic Processes on Earth

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Topic B - Geologic Processes on Earth Topic B - Geologic Processes on Earth 1 Chapter 6 - ELEMENTS OF GEOLOGY 6-1 The Original Planet Earth Planet Earth formed out of the original gas and dust that prevailed at the origin of the solar system some 4.6 billion years ago. It is the only known habitable planet so far. This is due to the concurrence of special conditions such as its position with respect to the Sun giving it the right temperature range, the preponderance of necessary gases and a shielding atmosphere that protects it from lethal solar radiation. Early Earth has however not always been so welcoming to life. Initially Earth was rich in silicon, iron and magnesium oxide. Heat trapped inside Earth along with radioactive decay which tends to produce more heat helped heavier elements to sink to the depths leaving lighter elements closer to the surface. Within the first 500 million years, an inner core formed of mostly solid iron surrounded by a molten iron outer core. The mantle formed of rocks that can deform. The thin outer crust that sustains life is composed mostly of silicate rocks. The various natural processes inside and on the surface of Earth make it a dynamic system which has evolved into what we know now. These include the oceans and the continents, the volcanoes that form the mountains and erosion that erodes the landscape, earthquakes that shape the topography and the movement of earth’s crust through the plate tectonics process. mantle outer core crust inner core 35 700 2885 5155 6371 Depth in km Figure 6-1: Schematics showing the Earth’s solid inner core, liquid outer core, mantle and curst. The crust consists of continental and oceanic crusts. 2 Early Earth was full of toxic gases. Volcanoes released sulfur along with water vapor trapped in the magma buried deep inside. Water condensation formed oceans and the original atmosphere saturated with carbon dioxide. This created the right conditions for basic life to start in the oceans. Primitive algae (called Cyanobacteria) that formed in the oceans absorbed carbon dioxide and water, which along with sunlight produced oxygen and carbohydrates (essential for life) a couple of billion years ago. Earth hosted some life forms for that long and animal life for the last 600 million years. Humans have been around for around one million years. Homosapians have been around for some 200,000 years. Earth is a “live” planet because of its internal heat engine that drives most natural processes. Planets like Mars and Mercury are dead because they lack such dynamic internal heat mechanism. Heat convection inside Earth drives volcanoes and earthquakes that formed the oceans and the continents. Igneous rocks form when lava cools down. Plate tectonics and volcanoes form mountains. Weathering breaks down rocks into smaller components like pebbles and dirt. Glaciers and rivers transport sediments from mountains to lakes and oceans where sedimentary rocks form. The driving process for earthquakes and the formation of mountains is the movement of tectonic plates on the ocean floor. These are rigid plates that spread apart, collide into each other and slide one under the other at a subduction process. The continental crust is composed of granitic rocks while the oceanic crust is composed of basaltic rocks. The mantle is composed of peridotite rock. These are solid rocks that can deform and sustain convective flow under extreme heat. The core is composed mostly of iron and nickel. The outer core is liquid whereas the inner core is solid; silicon and oxygen makeup most of the elements in the crust and the other elements make up the rest. Silicon, oxygen and magnesium makeup most of the mantle composition. The only liquid part of the Earth interior is the outer core. 6-2 Plate Tectonics Outline of the coast on the eastern part of South America is similar to that of West Africa. Identical rock fossils on both sides pointed to the drift of the two continents over time. Actually, the continents of South Africa, South America, Oceania and Antartica formed a huge continent called Gondwana. Two supercontinents, Gondwana in the south and Laurasia in the north formed the original landmass called Pangea that existed from 510 to 180 million years ago. The breakup of Pangea some 180 million years ago gave the five continents that we know now. Continents have drifted apart over time. 3 Laurasia equator Gondwana Figure 6-2: Representation of the two original supercontinents (Gondwana and Laurasia) that were part of Pangea some 200 million years ago (during the Triassic period). Figure 6-3: Some 130 million years ago, the west coast of the US was located in Idaho Changes in the shape of continents over time includes the shrinking of the Pacific Ocean and the widening of the Atlantic Ocean, the continent of Africa running into Europe, Australia crashing into Asia, the widening of the Red Sea and Mount Everest getting taller. 4 World War II (1939-1945) brought about great deal of technological advances. Sonar radars were developed to detect submerged submarines. Sonar radars were used in the 1950s to map out the ocean floor. A mid-ocean ridge was discovered in the Atlantic Ocean floor formed by the flow of lava. Moreover, it was discovered in the 1960s that the sea floor was spreading at this ridge. Rocks become magnetized when they form from cooled lava at the mid-ocean ridge. Rocks close to the mid-ocean ridge contain stripes of weak and strong magnetic fields as well as the evidence of magnetic field reversals. The fact that the magnetic field pattern was the mirror image on both sides of the ridge center along with the other fact that drilled cores grew older as one moved away from the ridge is evidence of sea floor spreading. The reversal of Earth’s magnetic field occurred multitude of times, the last one going back to some 700,000 years ago. The ocean crust is not older than 200 million years while fossils on continents can be older than 700 million years. Old ocean crust gets covered over through the sea floor spreading process which acts as a conveyor belt laying new geologic material covering old one. Spreading is currently at a rate of a couple of centimeters per year. The occurrence of earthquakes, volcano eruptions, the formation of mountain ranges and ocean basins are all a consequence of plate tectonics, which became a unifying theme in geology. 6-3 Eras in Geologic History The geologic time line is divided into four main eons. (1) the Haddean from 4.6 to 3.8 billion years ago, (2) the Archean from 3.8 to 2.5 billion years ago, (3) the Proterozoic from 2.5 billion years ago to 542 million years ago, and (4) the Phanerozoic from 542 million years ago to now. This last eon, the Phanerozoic, is itself divided into three eras. (1) the Paleozoic from 542 and 251 million years ago, (2) the Mesozoic between 251 and 65 million years ago and (3) the Cenozoic from 65 million years ago to the present. Each era is itself is divided into many periods and each period is divided into epochs. Since these names are used in the literature, it’s nice to get exposed to them at least this once. 5 Figure 6-4: The geologic time scale is divided into eons, eras, periods and epochs. The Hadean eon started with the formation of Earth some 4.6 billion years ago. This date is based on dating meteorites and moon rocks. It took some 700 million years for heavy bombardment to stop and for Earth to cool down enough. It took another 375 million years for liquid water to form oceans. During the Archean eon, the atmosphere was rich in carbon dioxide. The oldest known rocks date back to 3.8 billion years ago and is the boundary between the Hadean and Archean eons. The Proterozoic eon saw an early form of life, which dates back to 2.5 billion years ago and is the boundary between the Archean and Proterozoic eons. An early life form (cyanobacteria) absorbed carbon dioxide and produced oxygen. Stromatolites are sheet-like sedimentary rocks formed from layers of cyanobacteria over past history; these are found in shallow water environments. During the Archean eon, photosynthesis started some 3.5 billion years ago. Then, it took some 1.5 billion years for basic life form to take hold in oceans at first. Multicellular organisms appeared some 1.25 billion years later. Plants and animals became abundant some 375 million years later. The first snowball Earth took place some 2.3 billion years ago during the 6 Proterozoic eon. Another major glaciation period took place between 800 and 635 million years ago. The next (Phanerozoic) eon saw the development of rich eras and periods due to the development of bony and hard shell creatures that left rich fossil evidence. Life expanded tremendously during the Paleozoic era, which is divided into the Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian and Permian periods. There was an outburst of complex life during the Cambrian period including the appearance of the first vertebrates. This is the referred to as the Cambrian explosion, which happened 530 million years ago. Continents were drifting apart and the climate was getting warmer. The world was full of shallow seas where life thrived at first. Over time, plants and animals made it out of the ocean and started to populate the land. The first vertebrate land animals appeared 380 million years ago. Oxygen levels increased due to photosynthesis. Collision between landmasses created mountains, which diversified the ecosystem.
Load more

Recommended publications
  • AGAP Antarctic Research Project Http
    AGAP Antarctic Research Project Image by Zina Deretsky, NSF Image from - http- //news.bbc.co.uk/1/hi/sci/tech/6145642 Build Your Gamburtsev Mountain Formation Mountain Building: Remember mountain ranges can be built in different ways. With the Gamburtsev Mountains there are several possible theories, but with the mountains under ice, there is little data available. Let’s focus on the two main theories, collision and hot spot volcanic activity. Select one theory to support. Your task is to create a model of your mountain building event and explain why you picked it, how your model supports your theory, and what ‘tools of the trade’ from our geophysical tools you could use to test your theory. The Gamburtsevs, the Result of a Collision? Mountain belts are formed along boundaries between the Earth’s crustal (lithospheric) plates. Remember, the Earth’s outside crust is made up of plates (or sections) with pieces that are slowly moving. When the different plates collide they can push or fold the land up forming raised areas, or mountains. The European Alps and the Himalayas formed this way. The sections of Earth’s continental crust are constantly shifting. During the Cambrian Period, a time between ~500 and 250 Ma, the piece of crust that would become Antarctica (we will call this proto-Antarctica) was on the move! Early in the Cambrian it was located close to the equator, a much Proto Antarctica Other Continent milder climate than its current location, but as the Cambrian Period advanced proto-Antarctica moved slowly south. The collision theory suggests that as these pieces of continent moved, like bumper cars they collided with each other.
    [Show full text]
  • Terræ Conceptions of Mountain Formation, Folding, Fault and the Continental Drift in Geography Textbooks Between the Decades Of
    Terræ ARTIGO 10.20396/td.v14i4.8654094 Didatica Conceptions of mountain formation, folding, fault and the continental drift in geography textbooks between the decades of 1930 to 1960 DANILO M. DA COSTA, EDSON R. DE SOUZA INSTITUTE OF GEOSCIENCES, GRADUATE PROGRAM OF TEACHING AND HISTORY OF EARTH SCIENCES. UNIVERSITY OF CAMpiNAS (CAMpiNAS STATE UNIVERSITY), ZEFERINO VAZ UNIVERSITY CAMPUS, RUA CARLOS GOMES, 250, BARÃO GERALDO, 13083-855, CAMpiNAS, SP. E-MAILS: [email protected], [email protected] Abstract: The conceptions about the origins of mountains, faults, folds or relief Manuscript: are very different if we compare didactic books of Geography published before Received: Quadrennial Conference of the International and after the elaboration of Plates Tectonics theory. In this article, it was analyzed Geoscience Education Organization th didactic books from first grade education, which is currently equivalent to the 6 Accepted: 14/01/2018 grade of Elementary School 2, published between 1933 until 1961. Obviously, by that time, Plate tectonics theory had not yet been elaborated. However, Citation: Costa D.M., Souza E.R. 2018. Conceptions of the academic world was already familiar with the Continental Drift theory, an mountain formation, folding, fault and the continental innovative proposal elaborated at the beginning of the 20th century by German drift in geography textbooks between the decades of scientist Alfred Wegener [1880-1930]. According to Wegener, the continents 1930 to 1960. Terræ Didatica, 14(4):349-354. URL: were together millions of years ago, forming a single great mass, called by http://www.ige.unicamp.br/terraedidatica/. him of “Pangea”. Considering that the books analyzed were published between 1933 and 1961, such works could be expected to contemplate and explain the Keywords: Plate Tectonics, continental drift, mountain continental drift theory.
    [Show full text]
  • The Early Stages of Subduction
    The early stages of subduction Dr Douwe J J van Hinsbergen reflects on his efforts to shed new light on the mechanisms of plate SINK tectonics, attempting to determine the processes that lead to the formation of new subduction zones From what context did your investigation make plate reconstructions of these mountain into Subduction Initiation reconstructed from belts. Normal plate reconstructions assume Neotethyan Kinematics (SINK) emerge? that plates are rigid, they cannot deform and their motion is accommodated along narrow, During my PhD and first two postdoctoral discrete fault zones. Although this approach positions, I studied the formation and evolution is very useful for reconstructing plate motion of mountain belts in the wider Neotethyan on a global scale, it is not directly applicable realm. The Neotethys was a major oceanic to regions where plates converge and where basin system that existed between Gondwana one plate subducts below another – in in the south (a major continental realm that these places, plate boundary zones show contained Africa, Arabia, India and Australia) distributed, spectacular deformation. Using and Laurasia in the north (Eurasia, Greenland structural geological and palaeomagnetic and North America). Its closure eventually data, I have built detailed retro-deformation formed the Alpine-Himalayan mountain belt. models of these mountain belts. From these models, I can derive when and where During my third postdoctoral position at the subduction zones started to form, and along University of Oslo in Norway, I started to what structures. 106 INTERNATIONAL INNOVATION SINK Can you provide an overview of your approach to study the driving forces behind back to the time of their onset, we aim to current project and outline the main aims plate tectonics? define what processes cause the formation of your research? of subduction zones.
    [Show full text]
  • Lesson 3: Sea Floor to Summit
    Everest Education Expedition Curriculum Lesson 3: Sea Floor To Summit Created by Montana State University Extended University and Montana NSF EPSCoR http://www.montana.edu/everest Lesson Overview: Explore the rocks that lie beneath Mount Everest’s summit. Simulate the formation of the Himalayan Mountains and Mount Everest while uncovering the dynamic processes of plate tectonics. Study the rocky layers that Dr. David Lageson researched on Mount Everest and investigate the geologic layers that sit below each climber’s crampons (ice cleats). Discover how the ancient sea floor now sits on this extreme summit and ponder whether Mount Everest really is the tallest mountain on earth. Objectives: Students will be able to: 1. Explain how the Himalayan Mountains formed. 2. Identify the rock layers of Mount Everest. 3. Explain the different ways each of the world’s four “tallest” mountains are measured. Vocabulary: fault - a crack with offset in the Earth's crust folding - when rocks or rock layers that were once flat are bent or curved gneiss (nice) - a high-grade metamorphic rock formed from preexisting granite or sedimentary rock (high grade metamorphism changes the rock so completely that the source rock often cannot be readily identified) Read more: http://www.answers.com/topic/metamorphism#ixzz1oxKeAZaE granite - an igneous rock that forms from the slow crystallization of silica-rich magma below Earth’s surface limestone - a sedimentary rock composed mostly of calcium carbonate formed in clear, warm, shallow marine waters marble - a metamorphic
    [Show full text]
  • The Geology of the Burke Quadrangle, Vermont
    THE GEOLOGY OF THE BURKE QUADRANGLE, VERMONT By BERTRAM G. WOODLAND off tC 200 STE STREET VERMONT GEOLOGICAL SURVEY CHARLES G. DOLL, State Geologist Published by VERMONT DEVELOPMENT DEIARTMENT MONTPELIER, VERMONT BULLETIN No. 28 1965 - Fiure 1. Fiontispie c Burke Mountain, Umpire \Iountain (left), and the northern spur of Kirby Mountain right) are resistant e-'se' of homteled Gilc \lount'&in fonuttion jj nuuite. View southeist\vards from near Marshall Swhool. TABLE OF CONTENTS PAGE ABSTRACT 9 INTRODUCTION ...................... 10 Location ........................ 10 Methods of study .................... 10 Acknowledgments .................... 12 Physiography ...................... 14 Settlement ....................... 17 Previous work ..................... 18 STRATIGRAPHY ...................... 19 General statement .................... 19 Thicknesses ..................... 19 Age of formations ................... 20 Sequence ....................... 20 Albee Formation ..................... 21 Amphibolite ...................... 22 Waits River Formation ................. 23 Impure limestone ................... 23 Pelitic rocks . . . . . . . . . . . . . . . . . . . . 24 Psammitic beds .................... 25 Amphibolite ...................... 27 Light-colored hornblende quartzose bands . . . . . . . 31 Meta-acid igneous rocks ................ 31 Gile Mountain Formation ................. 34 Quartzose phvllite ....................35 Pelitic rocks ...................... 39 Amphibolite . . . . . . . . . .
    [Show full text]
  • Redalyc.Timing and Implications of Late Cretaceous Tectonic And
    Geologica Acta: an international earth science journal ISSN: 1695-6133 [email protected] Universitat de Barcelona España Mitchell, S.F. Timing and implications of Late Cretaceous tectonic and sedimentary events in Jamaica Geologica Acta: an international earth science journal, vol. 4, núm. 1-2, 2006, pp. 171-178 Universitat de Barcelona Barcelona, España Available in: http://www.redalyc.org/articulo.oa?id=50540209 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Geologica Acta, Vol.4, Nº1-2, 2006, 171-178 Available online at www.geologica-acta.com Timing and implications of Late Cretaceous tectonic and sedimentary events in Jamaica S.F. MITCHELL Department of Geography and Geology, University of the West Indies Mona, Kingston 7, Jamaica. Email: [email protected] ABSTRACT The Cretaceous succession in Jamaica can be divided into sedimentary packages bounded by major unconfor- mities (synthems). On the base of biostratigraphy and ages derived from strontium isotope ratios, these uncon- formities have been dated as Early Santonian, Late Campanian-Early Maastrichtian and Early Eocene. Each unconformity is also characterised by the widespread deposition of shallow water limestones, and a further shal- low limestone depositional event occurred in the late Middle Campanian. Some unconformities can be related to known tectonic events (based on either Burke-type or Pindell-type models) that affected the Caribbean region. The Early Santonian event is widespread and occurred shortly after the creation of the Caribbean Large Igneous Province.
    [Show full text]
  • Mountain Formation
    Mountain formation 2 Listen and read the text about mountains. Which type of mountains are formed when: a magma erupts from under the Earth? b magma pushes up under the Earth, but doesn’t erupt? c two tectonic plates push together? d water or wind cut away the land? e rock is pushed up through a crack in the Earth? The top layer of the Earth (the crust) is divided into seven large, independent sections, called tectonic plates. Below the Earth’s crust is the mantle – a layer of very hot, solid rock with some semi-molten rock called magma. Most mountains are formed by the movement of tectonic plates and rising magma. 1 Fold mountains are created when two tectonic plates collide. Their edges push together and up, causing mountains to be formed where they meet. Example: the Himalayas in Asia, the Alps in Europe Venture Level 2 . Mountain formation, p.255 © Oxford University Press PHOTOCOPIABLE 2 Fault-block mountains are formed when rock is forced up a crack in the Earth’s crust. They usually have a steep front and a sloping back. Example: the Sierra Nevada Mountains in North America 3 Volcanic mountains are created when magma pushes through the Earth’s crust and erupts. The material that erupts falls on the ground and becomes solid. With each future eruption, this material gradually builds into a mountain. Example: Mount Fuji in Japan 4 Dome mountains occur when magma pushes up under the Earth’s crust without erupting. The magma then cools and hardens, leaving a dome-shaped mountain.
    [Show full text]
  • A Stratigraphic and Geochronologic Analysis of the Morrison Formation/Cedar Mountain Formation Boundary, Utah
    Brigham Young University BYU ScholarsArchive Theses and Dissertations 2006-07-08 A Stratigraphic and Geochronologic Analysis of the Morrison Formation/Cedar Mountain Formation Boundary, Utah Brent W. Greenhalgh Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd Part of the Geology Commons BYU ScholarsArchive Citation Greenhalgh, Brent W., "A Stratigraphic and Geochronologic Analysis of the Morrison Formation/Cedar Mountain Formation Boundary, Utah" (2006). Theses and Dissertations. 916. https://scholarsarchive.byu.edu/etd/916 This Thesis is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. A STRATIGRAPHIC AND GEOCHRONOLOGIC ANALYSIS OF THE MORRISON FORMATION/CEDAR MOUNTAIN FORMATION BOUNDARY, UTAH by Brent W. Greenhalgh A thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Master of Science Copyright © 2006 Brent W. Greenhalgh All Rights Reserved BRIGHAM YOUNG UNIVERSITY GRADUATE COMMITTEE APPROVAL of a thesis submitted by Brent W. Greenhalgh This thesis has been read by each member of the following graduate committee and by majority vote has been found to be satisfactory. ________________________ ______________________________________ Date Brooks B. Britt, Chair ________________________ ______________________________________
    [Show full text]
  • Convergent Plate Margin Dynamics: New Perspectives from Structural Geology, Geophysics and Geodynamic Modelling
    Tectonophysics 483 (2010) 4–19 Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Convergent plate margin dynamics: New perspectives from structural geology, geophysics and geodynamic modelling W.P. Schellart a,⁎, N. Rawlinson b a School of Geosciences, Monash University, Melbourne, VIC 3800, Australia b Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia article info abstract Article history: Convergent plate margins occur when two adjoining tectonic plates come together to form either a Received 26 May 2009 subduction zone, where at least one of the converging plates is oceanic and plunges beneath the other into Received in revised form 28 August 2009 the mantle, or a collision zone, where two continents or a continent and a magmatic arc collide. Convergent Accepted 31 August 2009 plate margins are arguably the most complicated and dynamic plate boundaries on Earth and have been the Available online 10 September 2009 subject of many investigations and discussions since the advent of plate tectonic theory. This paper provides a historical background and a review of the development of geological and geodynamic theories on Keywords: convergent plate margins. Furthermore, it discusses some of the recent advances that have been made in the Convergent plate margin fi Subduction elds of structural geology, geophysics and geodynamics, which are fundamental to our understanding of Collision this phenomenon. These include: (1) the finding that plates and plate boundaries move at comparable Orogenesis velocities across the globe; (2) the emerging consensus that subducted slabs are between two to three orders Slab of magnitude stronger than the ambient upper mantle; (3) the importance of lateral slab edges, slab tearing Plate tectonics and toroidal mantle flow patterns for the evolution of subduction zones; and (4) clear evidence from mantle tomography that slabs can penetrate into the lower mantle.
    [Show full text]
  • Chapter 10 Plate Tectonics
    Chapter 10 Plate Tectonics Learning Objectives After carefully reading this chapter, completing the exercises within it, and answering the questions at the end, you should be able to: • Discuss some of the early evidence for continental drift and Alfred Wegener’s role in promoting this theory. • Explain some of the other models that were used early in the 20th century to understand global geological features. • Describe the numerous geological advances made in the middle part of the 20th century that provided the basis for understanding the mechanisms of plate tectonics and the evidence that plates have moved and lithosphere is created and destroyed. • List the seven major plates, their extents, and their general directions of motion, and identify the types of boundaries between them. • Describe the geological processes that take place at divergent and convergent plate boundaries, and explain the existence of transform faults. • Explain how super-continents form and how they break apart. • Describe the mechanisms for plate movement. As we discovered in Chapter 1, plate tectonics is the model or theory that we use to understand how our planet works. More specifically it is a model that explains the origins of continents and oceans, folded rocks and mountain ranges, igneous and metamorphic rocks, earthquakes (Figure 10.0.1) and volcanoes, and continental drift. Plate tectonics was first proposed just over 100 years ago, but did not become an accepted part of geology until about 50 years ago. It took 50 years for this theory to be accepted for a few reasons. First, it was a true revolution in thinking about Earth, and that was difficult for many established geologists to accept.
    [Show full text]
  • Subduction Zone Backarcs, Mobile Belts, and Orogenic Heat
    VVOL.OL. 115,5, NNO.O. 2 A PPUBLICATIONUBLICATION OFOF TTHEHE GGEOLOGICALEOLOGICAL SSOCIETYOCIETY OOFF AAMERICAMERICA FFEBRUARYEBRUARY 22005005 Subduction zone backarcs, mobile belts, and orogenic heat Inside: Subduction zone backarcs, mobile belts, and orogenic heat, ROY D. HYNDMAN, CLAIRE A. CURRIE, AND STEPHANE P. M AZZOTTI, p. 4 2004–2005 Division Officers and Past Chairs, p. 11 GeoVentures™ 2005, p. 29 An Earth Scientist’s Periodic Table of the Elements and Their Ions by L. Bruce Railsback An Earth Scientist’s Periodic Table of the Elements and form as ions rather than in elemental form. The immediate Their Ions is a new periodic table designed to contextualize result is a completely rearranged table in which many trends in geochemistry, mineralogy, aqueous chemistry, elements appear multiple times, because many elements and other natural sciences. First published as an insert assume different charge under different natural conditions. in the September 2003 issue of Geology, this version is The practical result is that many trends in mineralogy, updated and supersized—36" by 76"! seawater chemistry, soil chemistry, the chemistry of This new periodic table of the elements is more useful Earth’s crust and mantle, the chemistry of sediments, and to earth scientists than the conventional periodic table nutrient chemistry become apparent in ways that are not used by chemists. The periodic table presented here recognizable on conventional, elementally constructed, acknowledges that most natural matter occurs in charged periodic tables. MCH092F, 1 folded sheet (36" × 76"), 7 p. text $25.00, member price $20.00—folded MCH092R, 1 rolled sheet (36" × 76"), 7 p.
    [Show full text]
  • Tectonics, Earthquakes, & Volcanism
    The Geosphere: Earth’s Interior & Surface During the twentieth century, new research revolutionized our understanding of Earth sci- ence. These discoveries explained how volcanoes such as Ecuador’s Tungurahua were formed and how the continents and oceans came Tectonics, to their present arrangement. The theory of plate tectonics—the main subject of this chapter—provides a Earthquakes, unified explanation for the pat- terns of earthquakes, volcanoes, and mountain building that domi- & Volcanism nate our planet. Events such as the March 2011 earthquake and tsunami that devastated Japan turn world attention to the Earth sciences, including physical geogra- 8 phy, for explanations. SAMPLE CHAPTER M08_CHRI4744_01_SE_C08.indd 2 30/09/15 1:00 AM What Are Earth’s History, Interior Structure, How Does Plate Tectonics Explain Changes 1 & Materials? 2 in Earth’s Surface? 8.1 The Vast Span of Geologic Time 8.4 Plate Tectonics 8.2 Earth’s History & Interior 8.5 Seafloor Spreading & Subduction Zones 8.3 The Rock Cycle 8.6 Plate Boundaries How Do Plate Motions Affect 3 Earth’s Crust? 8.7 Deformation, Folding, & Faulting 8.8 Earthquakes 8.9 Volcanoes 8.10 Mountain Building Mount Tungurahua in Ecuador is one of many active volcanoes in the Andes mountain chain that extends along the western coast of South America. SAMPLE CHAPTER M08_CHRI4744_01_SE_C08.indd 3 30/09/15 1:00 AM 4 What Are Earth’s History, Interior Structure, & Materials? 8.1 The Vast Span of Geologic Time Key Learning Concepts ago” shown on the time scale. In contrast, relative time is ▶ Describe the geologic time scale.
    [Show full text]