Introduction: the Global Overview

Total Page:16

File Type:pdf, Size:1020Kb

Introduction: the Global Overview Introduction 1 Introduction: the Global Overview I. Plate Tectonics and Geology of the Earth II. Overview of Northwest Geology III. Timeline for Northwest Geologic Events I. Plate Tectonics and Mohorovicic discontinuity (the Moho) occurs at the Geology of the Earth basethe ocean of the floor crust is where 3 miles there (5 km) is the below greatest sea level. change The in seismic velocity. The mantle is a dense hot layer of semi-solid rock about 1800-miles (2900 km) thick. It Earth’s Structure contains more iron, magnesium and calcium than the The Earth consists of three main layers: the crust, crust, and it is also hotter and denser than the crust. mantle, and core. The crust, which is the outer layer of The core is twice as dense as the mantle because it the Earth, is relatively thin and ridged. The continental consists of an iron-nickel alloy. It has two parts: a crust tends to be variable in thickness, averaging about 1360-mile-thick (2,200 km) liquid outer core and a 18-miles (30 km) thick; however, under mountain 775-mile-thick (1,250 km) solid inner core. The Earth’s ranges it may be 60-miles (100 km) thick. The oceanic crust is 3- to 6-miles (5 to 10 km) thick and most of core as the Earth rotates. magnetic field is created by spinning of the liquid outer Cross section showing the solid inner core, the liquid outer core, the mantle, and the crust. The asthenosphere is overlain by the lithosphere. 2 Idaho Geology Block diagram with east-west cross section across the the surface along the island arcs, it typically has the Japan Trench, Honshu and the Sea of Japan. At this composition of andesite. If the magma rises near the convergent plate boundary, Honshu is underlain by edge of the continent, it may form the great granitic continental crust. batholiths. Granite is less dense than basalt and can Earth’s Crust Oceanic Crust lining the ocean basins is made of easily float through it. basalt. The Continental crust is 15- to 43-miles (25 to 70 km) oceanic crust consists of olivine tholeiitic basalt and thick, ranging up to 43-miles (70 km) thick under isa dark,composed fine-grained of plagioclase volcanic feldspar, rock called pyroxenes and mountain ranges and high plateaus. One third of the olivine. The oceanic crust is 3.5- to 6-miles (5 to 10 Earth’s crust is continental because the ocean basins have very little continental crust. The upper 6 to 9 below sea level. The oceanic lithosphere is 30- to miles (10 to 15 km) of the crust is brittle and below 60-mileskm) thick (50 and to most 100 ofkm) the thick. ocean No floor ocean is 3 crust miles is (5 older km) that depth the crust is ductile. Continental crust is than 180 Ma. Basalt is derived from mantle material formed by the differentiation of from basaltic granite called peridotite that rises by convection cells or rock through the subduction process. As the basaltic mantle plumes to the Earth’s surface. As the material rises, the pressure drops because of less overlying gradually cools, becomes denser, and eventually sinks material. Pressure-release melting allows a lower- crust flows away from the ridge riding on the mantle, it as much as 435 miles (700 km) into the mantle at the density liquid (basaltic magma) to separate from the subduction zones. As the basaltic crust travels higher density mantle materials. So basalt, which is towards the subduction zone, the basalt absorbs richer in silicates than the parent peridotite, is also less water through the hydration of certain minerals. The dense. The basaltic magma is injected at the divergent newly hydrated silicate minerals have a lower melting plate boundaries (where two plates are pulling apart) temperature than the rest of the minerals. So as the and forms new crust. slab of basaltic crust is subducted into the mantle, Lithosphere and Asthenosphere. Because the the silicate-rich hydrate minerals melt. Because this upper mantle is cooler and more ridged than the deep melt is less dense than the surrounding material, it mantle, it behaves like the lower portion of the crust. Consequently, the crust and upper mantle together floats toward the surface. When the magma reaches Introduction 3 form the lithosphere or the tectonic plates. The than 120-miles (200 km) thick or twice the average thickness of the lithospheric plates ranges from 9 miles thickness of the continental lithosphere. Cratons have (15 km) for young oceanic lithosphere to more than a lower density than the oceanic crust so that they 120 miles (200 km) for old continental lithosphere. do not sink into the deep mantle. Cratons consist of However, the worldwide average is about 50 miles igneous and metamorphic rocks and range in age from (80 km) in thickness. The lithosphere overlies a hot, one- to four-billion-years old. These ancient crystalline mobile, semi-solid zone in the mantle referred to as the rocks are commonly referred to as the basement. At asthenosphere. The ridged lithosphere is believed to the central portion of the cratons, basement rocks are generally exposed but may be covered by much Tectonic plates or lithospheric plates are immense, younger sedimentary rocks and sediments around irregularlyfloat and move shaped on the slabs asthenosphere. of rock consisting of oceanic and continental lithosphere. Plate boundaries can covers the basement, it is called a platform. be accurately mapped from outer space by satellites. the margins. Where a thin layer of sedimentary rocks Theory of Plate Tectonics composed of granitic rocks, which consist of low- densityContinental minerals crust such floats as because quartz andit is feldspar.primarily By Since the 1840s, the geosynclinal theory was used to contrast, oceanic rocks are composed of denser explain the origin of mountain belts until the theory of plate tectonics gradually superseded it during the basaltic rocks. 1960s. Plate tectonics is now the great unifying theory of geology. Many geological and biological events, Cratons previously thought unrelated, can now be explained by The oldest and most stable part of continental plate tectonics. Although many geologists at the time lithosphere is referred to as a craton. Geologically more opposed the continental drift active rocks such as mountain belts typically surround (1915), there is now a consensus among geologists the cratons. Most cratons are situated in the interiors that the plate tectonic theory is idea valid. of Plate Alfred tectonics Wegener of tectonic plates and have survived many cycles of merging and rifting of islands and continents. Cratons amount of corroborating evidence from almost tend to have thick lithospheric roots and may be more everyhas been subdiscipline repeatedly of tested geology, and paleontology, confirmed by physics, a massive The major lithospheric plates and their movement directions. U.S. Geologic Survey. 4 Idaho Geology U.S. Geological Survey world map showing shield areas, platform areas and orogen areas. chemistry, and mathematics. This evidence includes accreted lithospheric fragments, which may be either of isotope dating, sediment-core analyses, deep-ocean continental or oceanic in origin, are called terranes if drilling, paleontology, seismology, paleomagnetism, andthey appear are of sufficient out-of-place, size theyand haveare referred consistent to as geological exotic heat-flow analysis, geochemistry, petrology, structural orattributes. suspect Where terranes terranes. Exotic do terranes not fit the are local transported geology continents,geology, acoustic-bottom geomorphology, profiling, and the seismic-reflection correlation of by tectonic plates and are accreted or attached to strata,profiling, fold gravity belts, andprofiling, mountain glaciation, ranges. fit Plate of the activities an existing continental landmass. As a result they have also had an enormous effect on the evolution of are geologically unrelated to the adjacent landmass life. along which they accreted. The geology of western North America is complicated by many exotic terranes Evidence of Plate Tectonic Activity Before consisting of volcanic island arcs, oceanic sediments, and oceanic lithosphere. Pangea Existed Ocean Magnetism tectonic processes since the breakup of supercontinent PangeaWe now somehave an200 excellent million understandingyears ago. Plate of processes plate Magnetometers are capable of sensing rock magnetism the oceanic crust is less than about 180 million years magnetism comes from the basaltic oceanic basement old.before Oceanic Pangea crust are appearsmore difficult to be recyclingto decipher about because every all becausemore than the a overlyingmile below sediments the ocean are floor. too Most weakly of the 150 million years. Consequently, all evidence of pre- Pangea plate movements must come from the existing The magnetic properties of the oceanic basement continents. There is now ample evidence that plate dependmagnetized on the to affectamount the of magnetometer magnetite, thickness significantly. of the tectonics have existed for most of the Earth’s history magnetized layer, and its depth below the surface. with several cycles of supercontinent formation. For Marine magnetic surveys are concerned only with example, it has been proposed that Pangea was formed from the breakup of parts of a 540-million-year-old direction of horizontal and vertical components. The measurements of the total field, not with magnitude or supercontinent called Rodinia. Along some continental border zones, geologists gammas at the magnetic equator to about 60,000 have recognized remnants of ancient volcanic arcs, gammasmagnitude at ofthe the magnetic total field poles. ranges from about 30,000 oceanic crust, and ocean sediments accreted onto In 1963 Fred Vine and Drummond Matthews the continental margins by plate tectonic processes observed that basalt along the central ridge of the that operated, in some cases, before Pangea. These Indian Ocean was magnetized with normal polarity. Introduction 5 “Magnetic stripes” on the ocean floor indicating reversals of the Earth’s magnetic field.
Recommended publications
  • Slip Rate of the Western Garlock Fault, at Clark Wash, Near Lone Tree Canyon, Mojave Desert, California
    Slip rate of the western Garlock fault, at Clark Wash, near Lone Tree Canyon, Mojave Desert, California Sally F. McGill1†, Stephen G. Wells2, Sarah K. Fortner3*, Heidi Anderson Kuzma1**, John D. McGill4 1Department of Geological Sciences, California State University, San Bernardino, 5500 University Parkway, San Bernardino, California 92407-2397, USA 2Desert Research Institute, PO Box 60220, Reno, Nevada 89506-0220, USA 3Department of Geology and Geophysics, University of Wisconsin-Madison, 1215 W Dayton St., Madison, Wisconsin 53706, USA 4Department of Physics, California State University, San Bernardino, 5500 University Parkway, San Bernardino, California 92407-2397, USA *Now at School of Earth Sciences, The Ohio State University, 275 Mendenhall Laboratory, 125 S. Oval Mall, Columbus, Ohio 43210, USA **Now at Department of Civil and Environmental Engineering, 760 Davis Hall, University of California, Berkeley, California, 94720-1710, USA ABSTRACT than rates inferred from geodetic data. The ously published slip-rate estimates from a simi- high rate of motion on the western Garlock lar time period along the central section of the The precise tectonic role of the left-lateral fault is most consistent with a model in which fault (Clark and Lajoie, 1974; McGill and Sieh, Garlock fault in southern California has the western Garlock fault acts as a conju- 1993). This allows us to assess how the slip rate been controversial. Three proposed tectonic gate shear to the San Andreas fault. Other changes as a function of distance along strike. models yield signifi cantly different predic- mechanisms, involving extension north of the Our results also fi ll an important temporal niche tions for the slip rate, history, orientation, Garlock fault and block rotation at the east- between slip rates estimated at geodetic time and total bedrock offset as a function of dis- ern end of the fault may be relevant to the scales (past decade or two) and fault motions tance along strike.
    [Show full text]
  • Kinematic Reconstruction of the Caribbean Region Since the Early Jurassic
    Earth-Science Reviews 138 (2014) 102–136 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Kinematic reconstruction of the Caribbean region since the Early Jurassic Lydian M. Boschman a,⁎, Douwe J.J. van Hinsbergen a, Trond H. Torsvik b,c,d, Wim Spakman a,b, James L. Pindell e,f a Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands b Center for Earth Evolution and Dynamics (CEED), University of Oslo, Sem Sælands vei 24, NO-0316 Oslo, Norway c Center for Geodynamics, Geological Survey of Norway (NGU), Leiv Eirikssons vei 39, 7491 Trondheim, Norway d School of Geosciences, University of the Witwatersrand, WITS 2050 Johannesburg, South Africa e Tectonic Analysis Ltd., Chestnut House, Duncton, West Sussex, GU28 OLH, England, UK f School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff CF10 3YE, UK article info abstract Article history: The Caribbean oceanic crust was formed west of the North and South American continents, probably from Late Received 4 December 2013 Jurassic through Early Cretaceous time. Its subsequent evolution has resulted from a complex tectonic history Accepted 9 August 2014 governed by the interplay of the North American, South American and (Paleo-)Pacific plates. During its entire Available online 23 August 2014 tectonic evolution, the Caribbean plate was largely surrounded by subduction and transform boundaries, and the oceanic crust has been overlain by the Caribbean Large Igneous Province (CLIP) since ~90 Ma. The consequent Keywords: absence of passive margins and measurable marine magnetic anomalies hampers a quantitative integration into GPlates Apparent Polar Wander Path the global circuit of plate motions.
    [Show full text]
  • Shape of the Subducted Rivera and Cocos Plates in Southern Mexico
    JOURNALOF GEOPHYSICAL RESEARCH, VOL. 100, NO. B7, PAGES 12,357-12,373, JULY 10, 1995 Shapeof the subductedRivera and Cocosplates in southern Mexico: Seismic and tectonicimplications Mario Pardo and Germdo Sufirez Insfitutode Geoffsica,Universidad Nacional Aut6noma de M6xico Abstract.The geometry of thesubducted Rivera and Cocos plates beneath the North American platein southernMexico was determined based on the accurately located hypocenters oflocal and te!eseismicearthquakes. The hypocenters ofthe teleseisms were relocated, and the focal depths of 21 eventswere constrainedusing a bodywave inversion scheme. The suductionin southern Mexicomay be approximated asa subhorizontalslabbounded atthe edges by the steep subduction geometryof theCocos plate beneath the Caribbean plate to the east and of theRivera plate beneath NorthAmerica to thewest. The dip of theinterplate contact geometry is constantto a depthof 30 kin,and lateral changes in thedip of thesubducted plate are only observed once it isdecoupled fromthe overriding plate. On thebasis of theseismicity, the focal mechanisms, and the geometry ofthe downgoing slab, southern Mexico may be segmented into four regions ß(1) theJalisco regionto thewest, where the Rivera plate subducts at a steepangle that resembles the geometry of theCocos plate beneath the Caribbean plate in CentralAmerica; (2) theMichoacan region, where thedip angleof theCocos plate decreases gradually toward the southeast, (3) theGuerrero-Oaxac.a region,bounded approximately by theonshore projection of theOrozco and O'Gorman
    [Show full text]
  • Plate Tectonics Review from Valerie Nulisch Some Questions (C) 2017 by TEKS Resource System
    Plate Tectonics Review from Valerie Nulisch Some questions (c) 2017 by TEKS Resource System. Some questions (c) 2017 by Region 10 Educational Service Center. Some questions (c) 2017 by Progress Testing. Page 2 GO ON A student wanted to make a model of the Earth. The student decided to cut a giant Styrofoam ball in half and paint the layers on it to show their thickness. 1 Which model below best represents the layers of the Earth? A B C D Page 3 GO ON 2 A student is building a model of the layers of the Earth. Which material would best represent the crust? F Grouping of magnetic balls G Styrofoam packing pellets H Bag of shredded paper J Thin layer of graham crackers 3 Your teacher has asked you to make a model of the interior of the Earth. In your model, how do the thicknesses of the lithosphere and crust compare? A The lithosphere is thinner than the crust. B The lithosphere is exactly the same thickness as the crust. C The lithosphere is thicker than the crust. D The lithosphere is thicker than the oceanic crust, but thinner than the continental crust. 4 Sequence the layers of the Earth in order from the exterior surface to the interior center. F Lithosphere, mantle, inner core, outer core, crust, asthenosphere G Inner core, outer core, mantle, asthenosphere, lithosphere, crust H Crust, mantle, outer core, inner core, asthenosphere, lithosphere J Crust, lithosphere, asthenosphere, mantle, outer core, inner core Page 4 GO ON 5 The tectonic plate labeled A in the diagram is the A Eurasian Plate B Indo-Australian Plate C Pacific Plate D African Plate Page 5 GO ON 6 The tectonic plate labeled B in the diagram is the — F Eurasian Plate G Indo-Australian Plate H Pacific Plate J North American Plate Page 6 GO ON Directions: The map below shows Earth's tectonic plates; six of them are numbered.
    [Show full text]
  • Kinematics of the Northern Walker Lane: an Incipient Transform Fault Along the Pacific–North American Plate Boundary
    Kinematics of the northern Walker Lane: An incipient transform fault along the Paci®c±North American plate boundary James E. Faulds Christopher D. Henry Nevada Bureau of Mines and Geology, MS 178, University of Nevada, Reno, Nevada 89557, USA Nicholas H. Hinz ABSTRACT GEOLOGIC SETTING In the western Great Basin of North America, a system of dextral faults accommodates As western North America has evolved 15%±25% of the Paci®c±North American plate motion. The northern Walker Lane in from a convergent to a transform margin in northwest Nevada and northeast California occupies the northern terminus of this system. the past 30 m.y., the northern Walker Lane has This young evolving part of the plate boundary offers insight into how strike-slip fault undergone widespread volcanism and tecto- systems develop and may re¯ect the birth of a transform fault. A belt of overlapping, left- nism. Tertiary volcanic strata include 31±23 stepping dextral faults dominates the northern Walker Lane. Offset segments of a W- Ma ash-¯ow tuffs associated with the south- trending Oligocene paleovalley suggest ;20±30 km of cumulative dextral slip beginning ward-migrating ``ignimbrite ¯are up,'' 22±5 ca. 9±3 Ma. The inferred long-term slip rate of ;2±10 mm/yr is compatible with global Ma calc-alkaline intermediate-composition positioning system observations of the current strain ®eld. We interpret the left-stepping rocks related to the ancestral Cascade arc, and faults as macroscopic Riedel shears developing above a nascent lithospheric-scale trans- 13 Ma to present bimodal rocks linked to Ba- form fault.
    [Show full text]
  • Regional Tectonic Systems of the Pacific Northwest Delineated from ERTS-1 Imagery
    University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1975 Regional tectonic systems of the Pacific Northwest delineated from ERTS-1 imagery Linda Kay Wackwitz The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Wackwitz, Linda Kay, "Regional tectonic systems of the Pacific Northwest delineated from ERTS-1 imagery" (1975). Graduate Student Theses, Dissertations, & Professional Papers. 7103. https://scholarworks.umt.edu/etd/7103 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. APR 1 6 1984 (iETo;,pr<i a 1384 ' r' r: ^ REGIONAL TECTONIC SYSTEMS OF THE PACIFIC NORTHWEST DELINEATED FROM ERTS-1 IMAGERY by Linda K. Wackwitz B.A. Colby College, 1972 Presented in partial fulfillment of the requirements for the degree of Master of Arts UNIVERSITY OF MONTANA 1975 Approved by Chairman, Board of Examiners / ^ f - / - - -- Dean, Graduate School I ,y. Date UMI Number: EP37904 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion.
    [Show full text]
  • Africa-Arabia-Eurasia Plate Interactions and Implications for the Dynamics of Mediterranean Subduction and Red Sea Rifting
    This page added by the GeoPRISMS office. Africa-Arabia-Eurasia plate interactions and implications for the dynamics of Mediterranean subduction and Red Sea rifting Authors: R. Reilinger, B. Hager, L. Royden, C. Burchfiel, R. Van der Hilst Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA, [email protected], Tel: (617)253 -7860 This page added by the GeoPRISMS office. Our proposed GeoPRISMS Initiative is based on the premise that understanding the mechanics of plate motions (i.e., the force balance on the plates) is necessary to develop realistic models for plate interactions, including processes at subduction and extensional (rifting) plate boundaries. Important advances are being made with new geologic and geophysical techniques and observations that are providing fundamental insights into the dynamics of these plate tectonic processes. Our proposed research addresses directly the following questions identified in the GeoPRISMS SCD Draft Science Plan: 4.2 (How does deformation across the subduction plate boundary evolve in space and time, through the seismic cycle and beyond?), 4.6 (What are the physical and chemical conditions that control subduction zone initiation and the development of mature arc systems?), and 4.7 (What are the critical feedbacks between surface processes and subduction zone mechanics and dynamics?). It has long been recognized that the Greater Mediterranean region provides a natural laboratory to study a wide range of geodynamic processes (Figure 1) including ocean subduction and continent- continent collision (Hellenic arc, Arabia-Eurasia collision), lithospheric delamination (E Turkey High Plateau, Alboran Sea/High Atlas), back-arc extension (Mediterranean basins, including Alboran, Central Mediterranean, Aegean), “escape” tectonics and associated continental transform faulting (Anatolia, North and East Anatolian faults), and active continental and ocean rifting (East African and northern Red Sea rifting, central Red Sea and Gulf of Aden young ocean rifting).
    [Show full text]
  • I. Convergent Plate Boundaries (Destructive Margins) (Colliding Plates)
    I. Convergent plate boundaries (destructive margins) (colliding plates) 1. Plates collide, an ocean trench forms, lithosphere is subducted into the mantle 2. Types of convergence—three general classes, created by two types of plates —denser oceanic plate subsides into mantle SUBDUCTION --oceanic trench present where this occurs -- Plate descends angle average 45o a. Oceanic-continental convergence 1. Denser oceanic slab sinks into the asthenosphere—continental plate floats 2. Pockets of magma develop and rise—due to water added to lower part of overriding crust—100-150 km depth 3. Continental volcanic arcs form a. e.g., Andes Low angle, strong coupling, strong earthquakes i. Nazca plate ii. Seaward migration of Peru-Chile trench b. e.g., Cascades c. e.g., Sierra Nevada system example of previous subduction b. Oceanic-oceanic convergence 1. Two oceanic slabs converge HDEW animation Motion at Plate Boundaries a. one descends beneath the other b. the older, colder one 2. Often forms volcanoes on the ocean floor 3. Volcanic island arcs forms as volcanoes emerge from the sea 200-300 km from subduction trench TimeLife page 117 Philippine Arc a. e.g., Aleutian islands b. e.g., Mariana islands c. e.g., Tonga islands all three are young volcanic arcs, 20 km thick crust Japan more complex and thicker crust 20-35 km thick c. Continental-continental convergence— all oceaninc crust is destroyed at convergence, and continental crust remains 1. continental crust does not subside—too buoyant 2. two continents collide—become ‘sutured’ together 3. Can produce new mountain ranges such as the Himalayas II. Transform fault boundaries 1.
    [Show full text]
  • Geologic History of Siletzia, a Large Igneous Province in the Oregon And
    Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot Wells, R., Bukry, D., Friedman, R., Pyle, D., Duncan, R., Haeussler, P., & Wooden, J. (2014). Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot. Geosphere, 10 (4), 692-719. doi:10.1130/GES01018.1 10.1130/GES01018.1 Geological Society of America Version of Record http://cdss.library.oregonstate.edu/sa-termsofuse Downloaded from geosphere.gsapubs.org on September 10, 2014 Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: Correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot Ray Wells1, David Bukry1, Richard Friedman2, Doug Pyle3, Robert Duncan4, Peter Haeussler5, and Joe Wooden6 1U.S. Geological Survey, 345 Middlefi eld Road, Menlo Park, California 94025-3561, USA 2Pacifi c Centre for Isotopic and Geochemical Research, Department of Earth, Ocean and Atmospheric Sciences, 6339 Stores Road, University of British Columbia, Vancouver, BC V6T 1Z4, Canada 3Department of Geology and Geophysics, University of Hawaii at Manoa, 1680 East West Road, Honolulu, Hawaii 96822, USA 4College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 CEOAS Administration Building, Corvallis, Oregon 97331-5503, USA 5U.S. Geological Survey, 4210 University Drive, Anchorage, Alaska 99508-4626, USA 6School of Earth Sciences, Stanford University, 397 Panama Mall Mitchell Building 101, Stanford, California 94305-2210, USA ABSTRACT frames, the Yellowstone hotspot (YHS) is on southern Vancouver Island (Canada) to Rose- or near an inferred northeast-striking Kula- burg, Oregon (Fig.
    [Show full text]
  • The Central Asia Collision Zone: Numerical Modelling of the Lithospheric Structure and the Present-Day Kinematics
    Th e Central Asia collision zone: numerical modelling of the lithospheric structure and the present - day kinematics Lavinia Tunini A questa tesi doctoral està subjecta a l a llicència Reconeixement - NoComercial – SenseObraDerivada 3.0. Espanya de Creative Commons . Esta tesis doctoral está sujeta a la licencia Reconocimiento - NoComercial – SinObraDerivada 3.0. España de Creative Commons . Th is doctoral thesis is license d under the Creative Commons Attribution - NonCommercial - NoDerivs 3.0. Spain License . The Central Asia collision zone: numerical modelling of the lithospheric structure and the present-day kinematics Ph.D. thesis presented at the Faculty of Geology of the University of Barcelona to obtain the Degree of Doctor in Earth Sciences Ph.D. student: Lavinia Tunini 1 Supervisors: Tutor: Dra. Ivone Jiménez-Munt 1 Prof. Dr. Juan José Ledo Fernández 2 Prof. Dr. Manel Fernàndez Ortiga 1 1 Institute of Earth Sciences Jaume Almera 2 Department of Geodynamics and Geophysics of the University of Barcelona This thesis has been prepared at the Institute of Earth Sciences Jaume Almera Consejo Superior de Investigaciones Científicas (CSIC) March 2015 Alla mia famiglia La natura non ha fretta, eppure tutto si realizza. – Lao Tzu Agradecimientos En mano tenéis un trabajo de casi 4 años, 173 páginas que no hubieran podido salir a luz sin el apoyo de quienes me han ayudado durante este camino, permitiendo acabar la Tesis antes que la Tesis acabase conmigo. En primer lugar quiero agradecer mis directores de tesis, Ivone Jiménez-Munt y Manel Fernàndez. Gracias por haberme dado la oportunidad de entrar en el proyecto ATIZA, de aprender de la modelización numérica, de participar a múltiples congresos y presentaciones, y, mientras, compartir unas cervezas.
    [Show full text]
  • Geological Evolution of the Red Sea: Historical Background, Review and Synthesis
    See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/277310102 Geological Evolution of the Red Sea: Historical Background, Review and Synthesis Chapter · January 2015 DOI: 10.1007/978-3-662-45201-1_3 CITATIONS READS 6 911 1 author: William Bosworth Apache Egypt Companies 70 PUBLICATIONS 2,954 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Near and Middle East and Eastern Africa: Tectonics, geodynamics, satellite gravimetry, magnetic (airborne and satellite), paleomagnetic reconstructions, thermics, seismics, seismology, 3D gravity- magnetic field modeling, GPS, different transformations and filtering, advanced integrated examination. View project Neotectonics of the Red Sea rift system View project All content following this page was uploaded by William Bosworth on 28 May 2015. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. Geological Evolution of the Red Sea: Historical Background, Review, and Synthesis William Bosworth Abstract The Red Sea is part of an extensive rift system that includes from south to north the oceanic Sheba Ridge, the Gulf of Aden, the Afar region, the Red Sea, the Gulf of Aqaba, the Gulf of Suez, and the Cairo basalt province. Historical interest in this area has stemmed from many causes with diverse objectives, but it is best known as a potential model for how continental lithosphere first ruptures and then evolves to oceanic spreading, a key segment of the Wilson cycle and plate tectonics.
    [Show full text]
  • The Tectonic Evolution of the Madrean Archipelago and Its Impact on the Geoecology of the Sky Islands
    The Tectonic Evolution of the Madrean Archipelago and Its Impact on the Geoecology of the Sky Islands David Coblentz Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM Abstract—While the unique geographic location of the Sky Islands is well recognized as a primary factor for the elevated biodiversity of the region, its unique tectonic history is often overlooked. The mixing of tectonic environments is an important supplement to the mixing of flora and faunal regimes in contributing to the biodiversity of the Madrean Archipelago. The Sky Islands region is located near the actively deforming plate margin of the Western United States that has seen active and diverse tectonics spanning more than 300 million years, many aspects of which are preserved in the present-day geology. This tectonic history has played a fundamental role in the development and nature of the topography, bedrock geology, and soil distribution through the region that in turn are important factors for understanding the biodiversity. Consideration of the geologic and tectonic history of the Sky Islands also provides important insights into the “deep time” factors contributing to present-day biodiversity that fall outside the normal realm of human perception. in the North American Cordillera between the Sierra Madre Introduction Occidental and the Colorado Plateau – Southern Rocky The “Sky Island” region of the Madrean Archipelago (lo- Mountains (figure 1). This part of the Cordillera has been cre- cated between the northern Sierra Madre Occidental in Mexico ated by the interactions between the Pacific, North American, and the Colorado Plateau/Rocky Mountains in the Southwest- Farallon (now entirely subducted under North America) and ern United States) is an area of exceptional biodiversity and has Juan de Fuca plates and is rich in geology features, including become an important study area for geoecology, biology, and major plateaus (The Colorado Plateau), large elevated areas conservation management.
    [Show full text]