DOCSLIB.ORG

Frontiers in Earth Sciences

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Frontiers in Earth Sciences

Series Editors: J.P. Brun, O. Oncken, H. Weissert, W.-C. Dullo

.

Dennis Brown • Paul D. Ryan

Editors

Arc-Continent Collision

Editors

Dr. Dennis Brown Instituto de Ciencias de la Tierra “Jaume Almera”, CSIC C/ Lluis Sole i Sabaris s/n 08028 Barcelona
Dr. Paul D. Ryan National University of Ireland, Galway Dept. Earth & Ocean Sciences (EOS) University Road Galway Ireland [email protected]
Spain [email protected]

This publication was grant-aided by the National University of Ireland, Galway ISBN 978-3-540-88557-3 DOI 10.1007/978-3-540-88558-0 Springer Heidelberg Dordrecht London New York e-ISBN 978-3-540-88558-0

Library of Congress Control Number: 2011931205 # Springer-Verlag Berlin Heidelberg 2011 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

Cover design: deblik, Berlin Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com)

Preface

One of the key areas of research in the Earth Sciences are processes that occur along the boundaries of the tectonic plates that make up Earth’s lithosphere. Of particular importance are the processes of tectonic accretion and erosion along convergent plate boundaries. One of the principal mechanisms of accretion occurs when intra-oceanic volcanic arcs collide with the margin of a continent in what is called arc–continent collision. Arc–continent collision has been one of the important tectonic processes in the formation of mountain belts throughout geological time and continues today along tectonically active plate boundaries such as those in the SW Pacific or the Caribbean. Well-constrained fossil arc–continent collision orogens supply the third and fourth dimension (depth and time) that are generally missing from currently active examples where tectonic processes such as subduction, uplift and erosion, and the formation of topography can be observed. Arc–continent collision is also thought to have been one of the most important processes involved in the growth of the continental crust over geological time, and may also play an important role in its recycling back into the mantle via subduction. The integration of research between active and fossil arc–continent orogens provide key data for the understanding of how plate tectonics works today, and how it might have worked in the past. Understanding the geological processes that take place during arc–continent collision is therefore of importance for our understanding of how collisional orogens evolve and how the continental crust grows or is destroyed. Furthermore, zones of arc–continent collision are producers of much of the worlds primary economic wealth in the form of minerals, so understanding the processes that take place during these tectonic events is of importance in modeling how this mineral wealth is formed and preserved.
Arc–continent collision orogeny is generally short-lived, lasting from c. 5 to
20 My, although much longer-lived regional events do occur. The duration of an arc–continent collision orogeny depends on a number of factors, among which the obliquity of the collision, the subduction velocity, and the structural architecture of the arc and the continental margin involved are of primary importance. In this book we define the onset of arc–continent collision as the arrival of the leading edge of the continental margin (continental crust to oceanic crust transition) at the subduction zone, something that is often difficult to identify in the geology of an orogen. Thinned, extended continental margins often reach 150–400 km in width and are highly structured. There is now widespread evidence that this thinned crust can be deeply subducted (>200 km) before being returned to the surface as high- and ultrahigh-pressure rocks. Dating these high-pressure rocks can provide important constraints on the timing of arrival of the continental margin at the subduction zone.

v

  • vi
  • Preface

A further constraint can be supplied by the arc volcanics, whose geochemistry may record the entrance of continentally derived sediments, or the thinned continental crust itself, into the subduction zone. In currently active systems, imaging the subducted continental lithosphere with techniques such as seismic tomography can also provide key data for determining the timing of on-set of collision and the rates at which the continental crust is being subducted. With the arrival of thicker continental crust (c. 20–30 km thick) at the subduction zone the developing orogen is generally uplifted to above sea level where it begins to erode and provide sediment to a foreland basin and across the arc–continent suture zone and the forearc. As convergence continues, the active volcanic front generally shuts down shortly after the entry of the continental crust into the subduction zone, and volcanic activity can move away from the subduction zone to continue outboard of it for some time before stopping completely. During the final stage of collision, a change in the location of the subduction zone can take place, further marking the end of the arc–continent collision. The final result of the arc–continent collision is a significant change in the structural architecture, composition, and rheology of the continental margin.
The aim of this book is to bring together a series of papers that are dedicated to the investigation of the tectonic processes that take place during arc–continent collision. A further aim is to investigate how tectonic processes influence the large-scale geological characteristics of these accretionary orogens and their mineral wealth. Finally, specific examples of arc–continent collisions are investigated. These range in age from the Neoproterozoic to those that are currently active, covering a large portion of geological time. To advance these aims, a series of points are developed which we attempt to address where possible in each paper. These points are: • The large-scale crust and mantle structure. • The nature and role of the lithosphere and asthenospheric mantle in the dynamics and chemistry of the subduction and collision processes.
• Processes that take place deep within the subduction channel in pure intraoceanic subduction and during the subduction of the continental crust.
• The geochemical and petrological evolution of the arc both before and during collision.
• The nature of the continental margin and its response to the collision. • The formation of topography and the erosion of the developing mountain belt to form a foreland and a suture forearc basin.
• Fore-arc subduction or accretion. • The emplacement of ophiolites and ultramafic massifs. • Metamorphism within the developing orogen. • The possibility of changes in the location of the post-collision subduction zone. • Place constraints on the duration of arc–continent collision orogeny. • Recycling, or growth and destruction of the continental crust.
The book is organised in four sections. In the first section, numerical modeling and natural examples are used to look at the three main players involved in arc– continent collision; the continental margin, the volcanic arc, and the subduction zone. In the second section, natural examples of arc–continent collisions are described. In the third section, modeling of various aspects of arc–continent collision are presented. In the fourth section, we bring together the material presented in the previous sections addressing the series of points outlined above and, where possible, attempt to provide answers to them.

  • Preface
  • vii

Finally, this publication was grant-aided by the Publications Fund of the National
University of Ireland, Galway. Also, we would like to extend our thanks to those who kindly provided reviews of the papers. This is an IGCP 524 publication.

Barcelona, Spain Galway, Ireland
Dennis Brown Paul D. Ryan

.

Contents

Part I The Main Players
1

23
Rifted Margins: Building Blocks of Later Collision ..................... 3

T. Reston and G. Manatschal Intra-oceanic Subduction Zones ......................................... 23 T.V. Gerya

The Subductability of Continental Lithosphere:

The Before and After Story .............................................. 53 J.C. Afonso and S. Zlotnik

45
The Seismic Structure of Island Arc Crust ............................. 87

A.J. Calvert

Vertical Stratification of Composition, Density, and Inferred Magmatic Processes in Exposed Arc Crustal Sections ................ 121

S.M. DeBari and A.R. Greene

  • 6
  • The Generation and Preservation of Mineral Deposits

in Arc–Continent Collision Environments ............................. 145

R.J. Herrington and D. Brown

Part II Specific Examples of Arc-Continent Collision
7

89
The Nature of the Banda Arc–Continent Collision

in the Timor Region ..................................................... 163 R. Harris

The Arc–Continent Collision in Taiwan ............................... 213

T. Byrne, Y.-C. Chan, R.-J. Rau, C.-Y. Lu, Y.-H. Lee, and Y.-J. Wang

Early Eocene Arc–Continent Collision in Kamchatka, Russia: Structural Evolution and Geodynamic Model ......................... 247

E. Konstantinovskaya

10 The Asia–Kohistan–India Collision: Review and Discussion ......... 279

J.-P. Burg

11 Processes of Arc–Continent Collision in the Uralides ................. 311

D. Brown, R.J. Herrington, and J. Alvarez-Marron

ix

  • x
  • Contents

12 The Record of Ordovician Arc–Arc and Arc–Continent Collisions in the Canadian Appalachians During the Closure of Iapetus ....... 341

A. Zagorevski and C.R. van Staal

13 Arc–Continent Collision in the Ordovician of Western Ireland:
Stratigraphic, Structural and Metamorphic Evolution ............... 373

P.D. Ryan and J.F. Dewey

14 Multiple Arc Development in the Paleoproterozoic Wopmay

Orogen, Northwest Canada ............................................. 403 F.A. Cook

Part III Models of Arc-Continent Collision Processes 15 The Origin of Obducted Large-Slab Ophiolite Complexes ........... 431

J.F. Dewey and J.F. Casey

16 Physical Modeling of Arc–Continent Collision: A Review of 2D, 3D, Purely Mechanical and Thermo‐Mechanical

Experimental Models .................................................... 445 D. Boutelier and A. Chemenda

Part IV Putting it All Together 17 Arc–Continent Collision: The Making of an Orogen ................. 477

D. Brown, P.D. Ryan, J.C. Afonso, D. Boutelier, J.P. Burg, T. Byrne, A. Calvert, F. Cook, S. DeBari, J.F. Dewey, T.V. Gerya, R. Harris, R. Herrington, E. Konstantinovskaya, T. Reston, and A. Zagorevski

Contributors

J.C. Afonso Department of Earth and Planetary Sciences, GEMOC ARC Key Centre for Geochemical Evolution and Metallogeny of Continents, Macquarie University, North Ryde, 2109 Sydney, NSW, Australia

J. Alvarez-Marron Instituto de Ciencias de la Tierra “Jaume Almera”, CSIC,

  • ´ ´ ´
  • c/Lluıs Sole i Sabarıs s/n, 08028 Barcelona, Spain

D. Boutelier Helmholtz Zentrum Potsdam, Deutsches GeoForschunsZentrum, Telegrafenberg, 14471 Potsdam, Germany

  • ´
  • ´
  • D. Brown Instituto de Ciencias de la Tierra “Jaume Almera”, CSIC, c/Lluıs Sole

  • ´
  • i Sabarıs s/n, 08028 Barcelona, Spain

J.P. Burg Department of Earth sciences, ETH- and University Zurich, Sonneggstrasse 5, CH 8092 Zurich, Switzerland

T. Byrne Center for Integrative Geosciences, University of Connecticut, Beach Hall, U-2045, 354 Mansfield Rd, Storrs, CT 06269, USA

A.J. Calvert Department of Earth Science, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada

J.F. Casey Department of Geosciences, University of Houston, Houston, TX, USA Y.-C. Chan Institute of Earth Sciences, Academia Sinica, 128, Sec. 2, Academia Road, Nangang, Taipei 11529, Taiwan

  • ´
  • ´
  • A. Chemenda Geoazur, Universite de Nice-Sophia Antipolis, CNRS, 250 av.

A. Einstein, 06560 Valbonne, France

F.A. Cook Department of Geoscience, University of Calgary, Calgary, AB T2N1N4, Canada

S.M. DeBari Geology Department, MS 9080, Western Washington University, Bellingham, WA 98225, USA

J.F. Dewey Department of Geology, UC Davis, One Shields Avenue, Davis, CA 95616, USA

T.V. Gerya Geophysical Fluid Dynamics Group, Institute of Geophysics, Department of Earth Sciences, Swiss Federal Institute of Technology (ETH- Zurich), Sonneggstrasse, 5, 8092 Zurich, Switzerland

xi

  • xii
  • Contributors

A. Greene Department of Geology and Geophysics, SOEST, University of Hawaii, Honolulu, HI 96822, USA

R. Harris Brigham Young University, Provo, UT, USA R.J. Herrington Department of Mineralogy, Natural History Museum, Cromwell Road, London SW7 5BD, England

M. Johnsen Department of Geology and Geophysics, SOEST, University of Hawaii, Honolulu, HI 96822, USA

E. Konstantinovskaya Institut national de la recherche scientifique, Centre Eau, Terre et Environnement (INRS-ETE), 490 de la Couronne, Quebec, QB G1K 9A9, Canada

Y.-H. Lee Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Chiayi 621, Taiwan

C.-Y. Lu Department of Geological Sciences, National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan

´
G. Manatschal IPGS-EOST, Universite de Strasbourg, 67084 Strasbourg, France R.-J. Rau Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan

T. Reston Earth and Environmental Sciences, School of Geography, University of Birmingham, Birmingham, UK

P.D. Ryan Earth and Ocean Sciences, National University of Ireland Galway, Galway, Ireland

C. van Staal Geological Survey of Canada, 625 Robson St, Vancouver, BC V6B5J3, Canada

Y.-J. Wang Institute of Geophysics, National Central University, 300 Jhongda Road, Jhungli, Taiwan

A. Zagorevski Geological Survey of Canada, 601 Booth St, Ottawa, ON K1A 0E8, Canada

S. Zlotnik School of Geosciences/School of Mathematical Sciences, Monash University, Clayton Campus, 3800 Melbourne, VIC, Australia. Currently at LaCaN, Laboratori de Calcul Numeric, Applied Mathematics Department III, UPC-Barcelona Tech, Jordi Girona 1–3, E-08034 Barcelona, Spain

The Editors

Dr. Dennis Brown is a senior research scientist at the Institute of Earth Sciences “Jaume Almera”, CSIC, in Barcelona, Spain. He obtained a Ph.D. in structural geology from Royal Holloway, University of London in 1994. His research interests lie in the general area of mountain building processes. Within this broad theme, he is especially interested in processes of arc–continent collision, the structure and kinematics of foreland thrust and fold belts, and the crustal-scale structure and geodynamics of collisional orogens. He is also active in petrophysical studies of the continental crust.

Dr. P.D. Ryan is Emeritus Professor of Geology at Earth and Ocean Sciences, National Univeristy of Ireland, Galway. He obtained a PhD in Geology from The University of Keele, North Staffordshire in 1974. His research interests include continental tectonics, finite element modelling of lithospheric scale processes, application of non-parametric statistics to geological problems, field geology in Western Europe and reform of geological higher education in the context of the Bologna Process. He has developed a special interest in the process of arc–continent collision during his 40 years of field experience in the Caledonides of western Ireland.

xiii

.

Recommended publications
  • Kinematic Reconstruction of the Caribbean Region Since the Early Jurassic

    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.
  • Evidence for Terrane Boundaries and Suture Zones Across Southern Mongolia Detected with a 2‑Dimensional Magnetotelluric Transect Matthew J

    Evidence for Terrane Boundaries and Suture Zones Across Southern Mongolia Detected with a 2‑Dimensional Magnetotelluric Transect Matthew J

    Comeau et al. Earth, Planets and Space (2020) 72:5 https://doi.org/10.1186/s40623-020-1131-6 FULL PAPER Open Access Evidence for terrane boundaries and suture zones across Southern Mongolia detected with a 2-dimensional magnetotelluric transect Matthew J. Comeau1* , Michael Becken1, Johannes S. Käuf2, Alexander V. Grayver2, Alexey V. Kuvshinov2, Shoovdor Tserendug3, Erdenechimeg Batmagnai2 and Sodnomsambuu Demberel3 Abstract Southern Mongolia is part of the Central Asian Orogenic Belt, the origin and evolution of which is not fully known and is often debated. It is composed of several east–west trending lithostratigraphic domains that are attributed to an assemblage of accreted terranes or tectonic zones. This is in contrast to Central Mongolia, which is dominated by a cratonic block in the Hangai region. Terranes are typically bounded by suture zones that are expected to be deep- reaching, but may be difcult to identify based on observable surface fault traces alone. Thus, attempts to match lithostratigraphic domains to surface faulting have revealed some disagreements in the positions of suspected terranes. Furthermore, the subsurface structure of this region remains relatively unknown. Therefore, high-resolution geophysical data are required to determine the locations of terrane boundaries. Magnetotelluric data and telluric-only data were acquired across Southern Mongolia on a profle along a longitude of approximately 100.5° E. The profle extends ~ 350 km from the Hangai Mountains, across the Gobi–Altai Mountains, to the China–Mongolia border. The data were used to generate an electrical resistivity model of the crust and upper mantle, presented here, that can contribute to the understanding of the structure of this region, and of the evolution of the Central Asian Orogenic Belt.
  • Thermochronology of the Miocene Arabia-Eurasia Collision Zone of Southeastern Turkey GEOSPHERE; V

    Thermochronology of the Miocene Arabia-Eurasia Collision Zone of Southeastern Turkey GEOSPHERE; V

    Research Paper GEOSPHERE Thermochronology of the Miocene Arabia-Eurasia collision zone of southeastern Turkey GEOSPHERE; v. 14, no. 5 William Cavazza1, Silvia Cattò1, Massimiliano Zattin2, Aral I. Okay3, and Peter Reiners4 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy https://doi.org/10.1130/GES01637.1 2Department of Geosciences, University of Padua, 35131 Padua, Italy 3Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak 34469, Istanbul, Turkey 4Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA 9 figures; 3 tables CORRESPONDENCE: william .cavazza@ unibo.it ABSTRACT ocean, and has been linked to mid-Cenozoic global cooling, Red Sea rifting, extension in the Aegean region, inception of the North and East Anatolian CITATION: Cavazza, W., Cattò, S., Zattin, M., Okay, The Bitlis-Pütürge collision zone of SE Turkey is the area of maximum in- strike-slip fault systems, and development of the Anatolian-Iranian continental A.I., and Reiners, P., 2018, Thermochronology of the Miocene Arabia-Eurasia collision zone of southeast- dentation along the >2400-km-long Assyrian-Zagros suture between Arabia and plateau (e.g., Şengör and Kidd, 1979; Dewey et al., 1986; Jolivet and Faccenna, ern Turkey: Geosphere, v. 14, no. 5, p. 2277–2293, Eurasia. The integration of (i) fission-track analyses on apatites, ii( ) (U-Th)/He 2000; Barazangi et al., 2006; Robertson et al., 2007; Allen and Armstrong, 2008; https:// doi .org /10 .1130 /GES01637.1. analyses on zircons, (iii ) field observations on stratigraphic and structural rela- Yılmaz et al., 2010). The age of the continental collision has been the topic of tionships, and (iv) preexisting U-Pb and Ar-Ar age determinations on zircons, much debate, with proposed ages ranging widely from the Late Cretaceous to Science Editor: Raymond M.
  • Download Preprint

    Download Preprint

    EarthArXiv Coversheet 29/04/2021 Caribbean plate boundaries control on the tectonic duality in the back-arc of the Lesser Antilles subduction zone during the Eocene N. G. Cerpa*, R. Hassani, D. Arcay, S. Lallemand, C. Garrocq, M. Philippon, J.-J. Cornée, P. Münch, F. Garel, B. Marcaillou, B. Mercier de Lépinay, and J.-F. Lebrun * corresponding author : [email protected] This manuscript is a non-peer reviewed preprint submitted to Tectonics and thus may be periodically revised. The final version will be available via the ‘Peer-review Publication DOI’ link on the right-hand side of this webpage. Please feel free to contact the corresponding author; we welcome feedback. Caribbean plate boundaries control on the tectonic duality in the back-arc of the Lesser Antilles subduction zone during the Eocene N. G. Cerpa1,2,*, R. Hassani2, D. Arcay1, S. Lallemand1, C. Garrocq1, M. Philippon3, J.-J. Cornée3, P. Münch1, F. Garel1, B. Marcaillou2, B. Mercier de Lépinay2, and J.-F. Lebrun3 1 Geosciences Montpellier, University de Montpellier, CNRS, Université des Antilles, Montpellier, France. 2 Geoazur, Université Côte d’Azur, CNRS, Observatoire de la Côte d’Azur, IRD, Valbonne, France. 3 Geosciences Montpellier, Université des Antilles, Université de Montpellier, CNRS, Guadeloupe, France. *Corresponding author: Nestor G. Cerpa ([email protected]) Abstract The Eocene tectonic evolution of the easternmost Caribbean Plate (CP) boundary, i.e. the Lesser Antilles subduction zone (LASZ), is debated. Recents works shed light on a peculiar period of tectonic duality in the arc/back-arc regions. A compressive-to-transpressive regime occurred in the north, while rifting and seafloor spreading occurred in Grenada basin to the south.
  • Pan-African Orogeny 1

    Pan-African Orogeny 1

    Encyclopedia 0f Geology (2004), vol. 1, Elsevier, Amsterdam AFRICA/Pan-African Orogeny 1 Contents Pan-African Orogeny North African Phanerozoic Rift Valley Within the Pan-African domains, two broad types of Pan-African Orogeny orogenic or mobile belts can be distinguished. One type consists predominantly of Neoproterozoic supracrustal and magmatic assemblages, many of juvenile (mantle- A Kröner, Universität Mainz, Mainz, Germany R J Stern, University of Texas-Dallas, Richardson derived) origin, with structural and metamorphic his- TX, USA tories that are similar to those in Phanerozoic collision and accretion belts. These belts expose upper to middle O 2005, Elsevier Ltd. All Rights Reserved. crustal levels and contain diagnostic features such as ophiolites, subduction- or collision-related granitoids, lntroduction island-arc or passive continental margin assemblages as well as exotic terranes that permit reconstruction of The term 'Pan-African' was coined by WQ Kennedy in their evolution in Phanerozoic-style plate tectonic scen- 1964 on the basis of an assessment of available Rb-Sr arios. Such belts include the Arabian-Nubian shield of and K-Ar ages in Africa. The Pan-African was inter- Arabia and north-east Africa (Figure 2), the Damara- preted as a tectono-thermal event, some 500 Ma ago, Kaoko-Gariep Belt and Lufilian Arc of south-central during which a number of mobile belts formed, sur- and south-western Africa, the West Congo Belt of rounding older cratons. The concept was then extended Angola and Congo Republic, the Trans-Sahara Belt of to the Gondwana continents (Figure 1) although West Africa, and the Rokelide and Mauretanian belts regional names were proposed such as Brasiliano along the western Part of the West African Craton for South America, Adelaidean for Australia, and (Figure 1).
  • Stylolites: Characteristics and Origin

    Stylolites: Characteristics and Origin

    • STYLOLITES: CHARACTERISTICS AND ORIGIN Joseph M. Montello A senior thesis submitted to fulfill the requirements for the degree of B.S. in Geology and Mineralogy • Winter Quarter, 1984 The Ohio State University ~2.~r·Thesis Advisor Department of Geology and Mineralogy Abstract • Stylolites are alternating interpenetrating columns of stone that form irregular interlocking partings or sutures in rock strata. They are most common along bedding planes of limestone but some are oblique or even perpendicular to bedding . Although the vast majority of stylolites occur in calcareous rocks, stylolites have been found in sandstone, quartzite and gypsum. The word "stylolite" refers to each individual column of stone. A cross section of a group of stylolites parallel to their length presents a rough, jagged line called a "stylolite seam" that resembles the sutures of a human skull. Stylolites always have a dark colored "clay" cap at the ends of the columns. The sides of the columns are typically discolored with a thin film of clay and show parallel flutings or striations that parallel their length. The shapes of individual stylolites vary greatly from broad flat­ • topped columns to pointed, jagged and tapering forms. After much controversy concerning the origin of stylolites, it is generally believed that they form by a process of chemical solution under pressure in lithified rock along some crack or seam. The interteething is produced because of differential solubilities and pressures within the rock unit. The clay cap on the stylolites is the non-soluble residue of the dissolved rock. Stylolites are only one of the possible end products in the spectrum of limestone responses to stress.
  • Collision Orogeny

    Collision Orogeny

    Downloaded from http://sp.lyellcollection.org/ by guest on October 6, 2021 PROCESSES OF COLLISION OROGENY Downloaded from http://sp.lyellcollection.org/ by guest on October 6, 2021 Downloaded from http://sp.lyellcollection.org/ by guest on October 6, 2021 Shortening of continental lithosphere: the neotectonics of Eastern Anatolia a young collision zone J.F. Dewey, M.R. Hempton, W.S.F. Kidd, F. Saroglu & A.M.C. ~eng6r SUMMARY: We use the tectonics of Eastern Anatolia to exemplify many of the different aspects of collision tectonics, namely the formation of plateaux, thrust belts, foreland flexures, widespread foreland/hinterland deformation zones and orogenic collapse/distension zones. Eastern Anatolia is a 2 km high plateau bounded to the S by the southward-verging Bitlis Thrust Zone and to the N by the Pontide/Minor Caucasus Zone. It has developed as the surface expression of a zone of progressively thickening crust beginning about 12 Ma in the medial Miocene and has resulted from the squeezing and shortening of Eastern Anatolia between the Arabian and European Plates following the Serravallian demise of the last oceanic or quasi- oceanic tract between Arabia and Eurasia. Thickening of the crust to about 52 km has been accompanied by major strike-slip faulting on the rightqateral N Anatolian Transform Fault (NATF) and the left-lateral E Anatolian Transform Fault (EATF) which approximately bound an Anatolian Wedge that is being driven westwards to override the oceanic lithosphere of the Mediterranean along subduction zones from Cephalonia to Crete, and Rhodes to Cyprus. This neotectonic regime began about 12 Ma in Late Serravallian times with uplift from wide- spread littoral/neritic marine conditions to open seasonal wooded savanna with coiluvial, fluvial and limnic environments, and the deposition of the thick Tortonian Kythrean Flysch in the Eastern Mediterranean.
  • Structural Evolution and Sequence of Thrusting in the High Himalayan, Tibetan-Tethys and Indus Suture Zones of Zanskar and Ladakh, Western Himalaya: Discussion

    Structural Evolution and Sequence of Thrusting in the High Himalayan, Tibetan-Tethys and Indus Suture Zones of Zanskar and Ladakh, Western Himalaya: Discussion

    Journal of Structural Geology, Vol. 10, No. 1, pp. 129 to 132, 1988 0191-8141/88 $03.00 + 0.00 Printed in Great Britain Pergamon Press pie Structural evolution and sequence of thrusting in the High Himalayan, Tibetan-Tethys and Indus Suture zones of Zanskar and Ladakh, Western Himalaya: Discussion P. B. KELEMEN Department of Geological Sciences A J-20, University of Washington, Seattle, WA 98195, U.S.A. I. REUBER Laboratoire de G~ologie Stratigraphique et Structurale, Universit~ de Poitiers, 40, Avenue du Recteur Pineau, 86022 Poitiers C6dex, France and G. FUCHS Geologische Bundesanstalt, Rasumofskygasse 23, A-1031 Wien, Austria (Received 19 May 1987; accepted 29 July 1987) M. P. Searle's recent paper in the Journal of Structural Reuber 1986). In addition, Eocene strata have been Geology (Searle 1986) included a major departure from identified in the melange at the base of the klippe published structural interpretations of the Ladakh (Colchen et al. in press). Thus the final emplacement of Himalaya. The geologic history of Ladakh is a vital key the klippe must post-date Lower Eocene sedimentation to understanding the timing and sequence of events (at least as young as 55 Ma). during the Himalayan orogeny. Ophiolitic rocks and Thrusting of the klippe may have begun substantially island arc volcanics along the Indus Suture zone (Frank earlier than its final emplacement, especially if the possi- et al. 1977, and many others) constitute remnants of a bility of intra-oceanic faulting (Reuber 1986) is con- broad oceanic basin, formerly north of the Indian craton. sidered as part of the emplacement 'event'.
  • Provenance of Sandstone Blocks and 1 Transition

    Provenance of Sandstone Blocks and 1 Transition

    The Yarlung suture mélange, Lopu Range, southern Tibet: Provenance of sandstone blocks and transition from oceanic subduction to continental collision Item Type Article Authors Metcalf, Kathryn; Kapp, Paul Citation The Yarlung suture mélange, Lopu Range, southern Tibet: Provenance of sandstone blocks and transition from oceanic subduction to continental collision 2017, 48:15 Gondwana Research DOI 10.1016/j.gr.2017.03.002 Publisher ELSEVIER SCIENCE BV Journal Gondwana Research Rights © 2017 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved. Download date 26/09/2021 15:58:40 Item License http://rightsstatements.org/vocab/InC/1.0/ Version Final accepted manuscript Link to Item http://hdl.handle.net/10150/626129 1 The Yarlung Suture Mélange, Lopu Range, Southern Tibet: Provenance of Sandstone Blocks and 2 Transition from Oceanic Subduction to Continental Collision 3 Kathryn Metcalf1* and Paul Kapp1 4 1Department of Geosciences, University of Arizona, Tucson, AZ, USA 5 *Corresponding author. Email: [email protected] 6 Abstract 7 With the aim of better understanding the history of ocean closure and suturing between 8 India and Asia, we conducted a geologic investigation of a siliciclastic matrix tectonic mélange 9 within the western Yarlung suture zone of southern Tibet (Lopu Range region, ~50 km northwest 10 of Saga). The siliciclastic matrix mélange includes abundant blocks of ocean plate stratigraphy 11 and sparse blocks of sandstone. Metapelite and metabasite blocks in the mélange exhibit lower 12 greenschist facies mineral assemblages, indicating that they were not deeply subducted. We 13 obtained detrital zircon U-Pb geochronologic and sandstone petrographic data from sandstone 14 blocks in the mélange and sandstone beds from Tethyan Himalaya strata exposed to the south of 15 the suture.
  • The Structure of a Major Suture Zone in the SW Iberian Massif: the Ossa-Morena/Central Iberian Contact

    The Structure of a Major Suture Zone in the SW Iberian Massif: the Ossa-Morena/Central Iberian Contact

    Tectonophysics 332 12001) 295±308 www.elsevier.com/locate/tecto The structure of a major suture zone in the SW Iberian Massif: the Ossa-Morena/Central Iberian contact J.F. Simancas*,D. MartõÂnez Poyatos,I. ExpoÂsito,A. Azor,F. Gonza Âlez Lodeiro Departamento de GeodinaÂmica, Universidad de Granada, Campus de Fuentenueva, Granada E-18002, Spain Abstract We have investigated the stratigraphy,structure and metamorphism of the boundary between the Ossa Morena Zone 1OMZ) and the Central Iberian Zone 1CIZ),two signi®cant continental portions of the Variscan Iberian Massif. The OMZ/CIZ contact is marked by a strongly deformed and metamorphosed NW±SE trending narrow band,namely,the Central Unit,in which partially retrogressed eclogites are included. During the Middle-Late Devonian the CIZ overthrust the OMZ,and in the footwall km-scale recumbent folds and thrusts developed with decoupling and underplating of the lower crust. At the same time,in the hanging wall there took place intense though localized back-folding and back-shearing. In the Early Carboniferous a transten- sional tectonic regime sank the overthrust block resulting in the exhumation of eclogites. These eclogites probably came from the underthrust OMZ lower crust,and they are at present included in the suture zone 1Central Unit) of this continental collision. The extension is responsible for the origin of a basin and bimodal magmatism on the southern border of the CIZ. A late episode of folding and fracturing signi®cantly contributed to the ®nal complex picture of this suture boundary. q 2001 Elsevier Science B.V. All rights reserved. Keywords: collision tectonics; eclogite exhumation; oblique extensional collapse; Variscan suture; SW Iberian Massif 1.
  • The Relationship Between Tectonic Stylolites and Fold Morphology in Limestones of the “Croatica Deposits” (Croatia)

    The Relationship Between Tectonic Stylolites and Fold Morphology in Limestones of the “Croatica Deposits” (Croatia)

    Geologia Croatica 55/1 79 - 81 4 Figs. ZAGREB 2002 The Relationship Between Tectonic Stylolites and Fold Morphology in Limestones of the “Croatica Deposits” (Croatia) Domagoj JAMIÈIÆ Key words: Stylolites, Tectonics, Compression, lolites appears in the plane perpendicular to the main Limestone, Croatica Deposits, Lower Pannonian, stress (s 1) whereas the second generation is connected Croatia. to extension of left transcurrent fault. This paper describes the tectonic deformational sequence which led to formational processes of tectonic stylolites in Pannonian clayey limestones (“Croatica Abstract Deposits”). The genetic link between faults and fracture Stylolites associated with axial plane fractures occur in Lower Pan- creation and the process of stylolitization under the nonian clayey limestones (the “Croatica Deposits”) from the “Ham- povica 6” deep exploration well. A genetic link has been observed influence of local stress with the same orientation has between the origin of fractures and the process of stylolitization. been noticed. Strong tectonic deformations are present which have been formed Stylolites often occur in limestones and marls, either under the influence of reverse bed faulting. Deformation is pro- nounced in the shape of folded marl layers along with the creation of a) parallel to, or b) at an angle relative to the bedding thick cleavage (0.3-0.5 cm). Along the fractures of axial plane cleav- plane. The first stylolite type, parallel to beds has been age, microlithons are separated and moved apart for similar values (2- formed as a result of gravity and sediment compaction. 5 mm) forming a moderate synform. Stylolites are formed in the last The initial thickness of sediments can be reduced by phase of structure shaping when the effects of the local compressional stress have weakened under the influence of which the breaking off gravitational processes up to 20-30% (TI©LJAR, 1978).
  • Location, Age, and Tectonic Significance of the Western Idaho Suture Zone (WISZ)

    Location, Age, and Tectonic Significance of the Western Idaho Suture Zone (WISZ)

    Location, Age, and Tectonic Significance of the Western Idaho Suture Zone (WISZ) By Robert J. Fleck1 and Robert E. Criss2 Open-File Report 2004-1039 Any use of trade names is for descriptive purposes only and does not imply endorsement by the Federal Government. U.S. Department of the Interior U.S. Geological Survey 1U.S. Geological Survey, 345 Middlefield Road (MS 937), Menlo Park, CA 94025 2Department of Earth and Planetary Sciences, Washington University, Campus Box 1169, St. Louis, MO 63130 1 LOCATION, AGE, AND TECTONIC SIGNIFICANCE OF THE WESTERN IDAHO SUTURE ZONE (WISZ) By ROBERT J. FLECK and ROBERT E. CRISS ABSTRACT The Western Idaho Suture Zone (WISZ) represents the boundary between crust overlying Proterozoic North American lithosphere and Late Paleozoic and Mesozoic intraoceanic crust accreted during Cretaceous time. Highly deformed plutons constituted of both arc and sialic components intrude the WISZ and in places are thrust over the accreted terranes. Pronounced variations in Sr, Nd, and O isotope ratios and in major and trace element composition occur across the suture zone in Mesozoic plutons. The WISZ is located by an abrupt west to east increase in initial 87Sr/86Sr ratios, traceable for over 300 km from eastern Washington near Clarkston, east along the Clearwater River thorough a bend to the south of about 110° from Orofino Creek to Harpster, and extending south-southwest to near Ola, Idaho, where Columbia River basalts conceal its extension to the south. K-Ar and 40Ar/39Ar apparent ages of hornblende and biotite from Jurassic and Early Cretaceous plutons in the accreted terranes are highly discordant within about 10 km of the WISZ, exhibiting patterns of thermal loss caused by deformation, subsequent batholith intrusion, and rapid rise of the continental margin.