DOCSLIB.ORG

Kinematic Evolution and Structural Styles of Fold-And-Thrust Belts

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Kinematic Evolution and Structural Styles of Fold-And-Thrust Belts Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 Kinematic evolution and structural styles of fold-and-thrust belts J. POBLET1* & R. J. LISLE2 1Departamento de Geologı´a, Universidad de Oviedo, C/Jesu´s Arias de Velasco s/n, 33005 Oviedo, Spain 2School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff CF10 3YE, UK *Corresponding author (e-mail: [email protected]) Abstract: Fold-and-thrust (FAT) belts occur worldwide and have long been the focus of research of structural geologists who have devised a variety of techniques to image, characterize and model their main structural features. This introductory chapter reviews the principal geological features of FAT belts formed in different settings, emphasizing aspects related to their kinematic evolution and structural styles. Despite great advances, challenges remain, particularly in the understanding of the spatial and temporal evolution (4D) of FAT belts and their controlling factors. These research efforts are being assisted by the growing availability to researchers of relatively new tools to collect field data, high quality 3D seismic data, and computer and laboratory modelling tools. This volume includes technical papers presented in the conference ‘International Meeting of Young Researchers in Structural Geology and Tectonics (YORSGET-08)’ held in Oviedo (Spain), together with other papers on the same theme. These papers deal with FAT belts in different parts of the world and cover a broad range of different aspects, from detailed structural analysis of single structures to regional issues, and from studies based on classical field structural geology to modelling. Fold-and-thrust belts, or FAT belts for short, have a The application of classical methods of studying worldwide distribution (see surveys in Nemcok deformation mechanisms in rocks and of quantify- et al. 2005; Cooper 2007), have formed in all eras ing geological strain (e.g. Ramsay 1967; Durney of geological time, and are widely recognized as & Ramsay 1973; Fry 1979a, b) to FAT belts has the most common mode in which the crust accom- led to greater understanding of deformation on a modates shortening. Generations of geologists have small scale and has given insights into the mechan- struggled to understand their origin, geometry, evol- isms responsible for the development of individual ution and the control exerted on them by different structures such as folds and faults. A number of structural, tectonic, stratigraphic and petrological techniques were initially devised to analyze the parameters (see for instance monographic books structure of FAT belts, for example: (a) balanced such as McClay & Price 1981; MacQueen & and restored cross-sections (e.g. Dahlstrom 1969; Leckie 1992; McClay 1992a, 1994; Mitra & Fisher Mitra & Namson 1989); (b) construction of geologi- 1992; Nemcok et al. 2005; Lacombe et al. 2007). cal cross-sections using techniques such as depth to A number of factors have contributed to our detachment estimations (e.g. Chamberlin 1910; greater understanding of the structure of FAT Mitra & Namson 1989) and the Busk and dip belts; some of them derive from detailed analyses domain methods (Busk 1929; Suppe 1985, respect- of prevalent patterns of faulting and folding and ively); and (c) advances in the understanding of their related structural features, whereas others quantitative relationships between thrusts and their come from other earth science disciplines. Many related folds and the rules to help to constrain the important concepts were developed and applied structural geometries (Suppe 1983; Jamison 1987; to FAT belts as early as the 1970s, or even before, Mitra 1990; Suppe & Medwedeff 1990). These tech- and have been subsequently modified. Since a com- niques have enabled construction and validation of prehensive historical review of research progress admissible and retro-deformable geological sections is almost impossible here, only a few important across single structures, structural units and entire landmarks are briefly described, starting with struc- FAT belts. They have also provided guidelines for tural methods from small- to large-scale and seismic interpretation, and proved to be essential following with techniques applied to these regions tools in structural interpretation widely applied else- furnished by related disciplines such as petroleum where, particularly in areas of scarce and/or poor geology, geophysics, geomorphology, petrology quality data. The study of accretionary wedges and sedimentology. played a key role in the development of the From:Poblet,J.&Lisle, R. J. (eds) Kinematic Evolution and Structural Styles of Fold-and-Thrust Belts. Geological Society, London, Special Publications, 349, 1–24. DOI: 10.1144/SP349.1 0305-8719/11/$15.00 # The Geological Society of London 2011. Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 2 J. POBLET & R. J. LISLE Coulomb wedge theory (e.g. Davis et al. 1983; isotopes, magnetostratigraphy, fission tracks, cos- Dahlen et al. 1984). This theory, which incorporates mogenic nuclides, and so on (e.g. Vance & Mu¨ller the best of the gravity-driven v. surface force-driven 2003; Alle`gre 2008; Lisker et al. 2009; Dunai motion hypotheses, was a major step forward in the 2010) have enabled estimates to be derived for understanding of the kinematics and dynamics of both the timing and the short- and long-term rates FAT belts because it allowed the inclusion of the of motion of single structures and larger-scale tec- effects of gravity and topography and provided tonic processes. These have demonstrated, for answers to the problems of structure sequencing in instance, that synchronous movement of different these regions. thrusts is a significant feature in the kinematic evol- The contribution of geophysics has been hugely ution of FAT belts, which, in turn, has important beneficial to FAT belt research. In particular, since implications for thrust sequences and the balancing/ many belts contain major oil and gas accumulations restoration of cross-sections and forward modelling in structural traps, the geophysical explorations of thrust terrains. A great deal of recent research has carried out by the hydrocarbon industry have sup- been focused on the dynamic interaction between plied an enormous amount of subsurface data. FAT belt evolution and surficial processes such as From the early seismic experiments in the late syn-kinematic sedimentation, erosion, uplift and 1920s in the Zagros FAT belt and in Oklahoma subsidence from lithosphere-scale (e.g. Beaumont until the present day, seismic imaging has furnished et al. 1992; Kooi & Beaumont 1996) to individual additional constraints on the geological interpret- structure-scale (e.g. Riba 1976; Suppe et al. 1992; ation of the deep geometry of structures, which Hardy & Poblet 1994). Thus, whereas the geometry had previously relied on geological data collected of the syn-tectonic sediments and basins within the at the surface. Seismic has, in some cases, also FAT belts is influenced by development of struc- allowed mapping of subsurface structures that are tures, the latter in turn are themselves strongly decoupled from their surface structural expression. affected by sedimentation and erosion. In short, Without forgetting the important contribution studies based on tectonic geomorphology and made by some other branches of geophysics, such palaeoseismology, P–T–t paths, geochronology as gravimetry for constraining of the deep structural and surficial processes in FAT belts sparked an configuration, or palaeomagnetism in the under- increasing interest in quantitative modelling of the standing of rotations around vertical axes, one of evolution of these belts at various scales. the most important boons to mapping of FAT belts has been the development of 3D seismic survey methods. 3D seismic data volumes provide a con- Types of FAT belts tinuous and more accurate image of the subsurface than can be obtained with 2D seismic methods Summarizing the main features of FAT belts is not (Hart 1999). Aided by the development of structural an easy task because they are remarkably diverse. tools, for example, Geosec 3D, 3D Move, Lithotect Although they exhibit a number of common charac- and Gocad software packages to visualize, charac- teristics, no single map or cross-section can provide terize and model the 3D structure of folds and a universal portrayal of a FAT belt because many thrusts, 3D seismic is starting to supply answers, parameters exert an important influence on them particularly with respect to the questions of the (see, for instance, Fitz-Diaz et al. 2011). These geometry of structures along strike and whether factors include the plate tectonics setting in which structures evolve in a self-similar fashion, that is, they developed, whether only the cover or both the whether observed spatial variations in fold geome- cover and basement rocks are involved in the struc- try reflect temporal geometric evolution (Elliott tures, the role of mechanical stratigraphy, the pres- 1976; Means 1976), or whether they evolve through ence, distribution and thickness of a salt/shale different structural forms. detachment, the occurrence of syn-orogenic ero- The contributions of tectonic geomorphology sion and deposition leading to burial, the depth to and palaeo-seismology of mountain fronts (Bull detachment and the effective elastic thickness of 2007 and references therein) have helped to deter- the lithosphere (e.g. Royden 1993), the occurrence
Load more

Recommended publications
  • Linking Megathrust Earthquakes to Brittle Deformation in a Fossil Accretionary Complex
    ARTICLE Received 9 Dec 2014 | Accepted 13 May 2015 | Published 24 Jun 2015 DOI: 10.1038/ncomms8504 OPEN Linking megathrust earthquakes to brittle deformation in a fossil accretionary complex Armin Dielforder1, Hauke Vollstaedt1,2, Torsten Vennemann3, Alfons Berger1 & Marco Herwegh1 Seismological data from recent subduction earthquakes suggest that megathrust earthquakes induce transient stress changes in the upper plate that shift accretionary wedges into an unstable state. These stress changes have, however, never been linked to geological structures preserved in fossil accretionary complexes. The importance of coseismically induced wedge failure has therefore remained largely elusive. Here we show that brittle faulting and vein formation in the palaeo-accretionary complex of the European Alps record stress changes generated by subduction-related earthquakes. Early veins formed at shallow levels by bedding-parallel shear during coseismic compression of the outer wedge. In contrast, subsequent vein formation occurred by normal faulting and extensional fracturing at deeper levels in response to coseismic extension of the inner wedge. Our study demonstrates how mineral veins can be used to reveal the dynamics of outer and inner wedges, which respond in opposite ways to megathrust earthquakes by compressional and extensional faulting, respectively. 1 Institute of Geological Sciences, University of Bern, Baltzerstrasse 1 þ 3, Bern CH-3012, Switzerland. 2 Center for Space and Habitability, University of Bern, Sidlerstrasse 5, Bern CH-3012, Switzerland. 3 Institute of Earth Surface Dynamics, University of Lausanne, Geˆopolis 4634, Lausanne CH-1015, Switzerland. Correspondence and requests for materials should be addressed to A.D. (email: [email protected]). NATURE COMMUNICATIONS | 6:7504 | DOI: 10.1038/ncomms8504 | www.nature.com/naturecommunications 1 & 2015 Macmillan Publishers Limited.
    [Show full text]
  • GEO 2008 Conference Abstracts, Bahrain GEO 2008 Conference Abstracts
    GEO 2008 conference abstracts, Bahrain GEO 2008 Conference Abstracts he abstracts of the GEO 2008 Conference presentations (3-5 March 2008, Bahrain) are published in Talphabetical order based on the last name of the first author. Only those abstracts that were accepted by the GEO 2008 Program Committee are published here, and were subsequently edited by GeoArabia Editors and proof-read by the corresponding author. Several names of companies and institutions to which presenters are affiliated have been abbreviated (see page 262). For convenience, all subsidiary companies are listed as the parent company. (#117804) Sandstone-body geometry, facies existing data sets and improve exploration decision architecture and depositional model of making. The results of a recent 3-D seismic reprocessing Ordovician Barik Sandstone, Oman effort over approximately 1,800 square km of data from the Mediterranean Sea has brought renewed interest in Iftikhar A. Abbasi (Sultan Qaboos University, Oman) deep, pre-Messinian structures. Historically, the reservoir and Abdulrahman Al-Harthy (Sultan Qaboos targets in the southern Mediterranean Sea have been the University, Oman <[email protected]>) Pliocene-Pleistocene and Messinian/Pre-Messinian gas sands. These are readily identifiable as anomalousbright The Lower Paleozoic siliciclastics sediments of the amplitudes on the seismic data. The key to enhancing the Haima Supergroup in the Al-Haushi-Huqf area of cen- deeper structure is multiple and noise attenuation. The tral Oman are subdivided into a number of formations Miocene and older targets are overlain by a Messinian- and members based on lithological characteristics of aged, structurally complex anhydrite layer, the Rosetta various rock sequences.
    [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]
  • Part 3: Normal Faults and Extensional Tectonics
    12.113 Structural Geology Part 3: Normal faults and extensional tectonics Fall 2005 Contents 1 Reading assignment 1 2 Growth strata 1 3 Models of extensional faults 2 3.1 Listric faults . 2 3.2 Planar, rotating fault arrays . 2 3.3 Stratigraphic signature of normal faults and extension . 2 3.4 Core complexes . 6 4 Slides 7 1 Reading assignment Read Chapter 5. 2 Growth strata Although not particular to normal faults, relative uplift and subsidence on either side of a surface breaking fault leads to predictable patterns of erosion and sedi­ mentation. Sediments will fill the available space created by slip on a fault. Not only do the characteristic patterns of stratal thickening or thinning tell you about the 1 Figure 1: Model for a simple, planar fault style of faulting, but by dating the sediments, you can tell the age of the fault (since sediments were deposited during faulting) as well as the slip rates on the fault. 3 Models of extensional faults The simplest model of a normal fault is a planar fault that does not change its dip with depth. Such a fault does not accommodate much extension. (Figure 1) 3.1 Listric faults A listric fault is a fault which shallows with depth. Compared to a simple planar model, such a fault accommodates a considerably greater amount of extension for the same amount of slip. Characteristics of listric faults are that, in order to maintain geometric compatibility, beds in the hanging wall have to rotate and dip towards the fault. Commonly, listric faults involve a number of en echelon faults that sole into a low­angle master detachment.
    [Show full text]
  • Tectonics of the Musandam Peninsula and Northern Oman Mountains: from Ophiolite Obduction to Continental Collision
    GeoArabia, 2014, v. 19, no. 2, p. 135-174 Gulf PetroLink, Bahrain Tectonics of the Musandam Peninsula and northern Oman Mountains: From ophiolite obduction to continental collision Michael P. Searle, Alan G. Cherry, Mohammed Y. Ali and David J.W. Cooper ABSTRACT The tectonics of the Musandam Peninsula in northern Oman shows a transition between the Late Cretaceous ophiolite emplacement related tectonics recorded along the Oman Mountains and Dibba Zone to the SE and the Late Cenozoic continent-continent collision tectonics along the Zagros Mountains in Iran to the northwest. Three stages in the continental collision process have been recognized. Stage one involves the emplacement of the Semail Ophiolite from NE to SW onto the Mid-Permian–Mesozoic passive continental margin of Arabia. The Semail Ophiolite shows a lower ocean ridge axis suite of gabbros, tonalites, trondhjemites and lavas (Geotimes V1 unit) dated by U-Pb zircon between 96.4–95.4 Ma overlain by a post-ridge suite including island-arc related volcanics including boninites formed between 95.4–94.7 Ma (Lasail, V2 unit). The ophiolite obduction process began at 96 Ma with subduction of Triassic–Jurassic oceanic crust to depths of > 40 km to form the amphibolite/granulite facies metamorphic sole along an ENE- dipping subduction zone. U-Pb ages of partial melts in the sole amphibolites (95.6– 94.5 Ma) overlap precisely in age with the ophiolite crustal sequence, implying that subduction was occurring at the same time as the ophiolite was forming. The ophiolite, together with the underlying Haybi and Hawasina thrust sheets, were thrust southwest on top of the Permian–Mesozoic shelf carbonate sequence during the Late Cenomanian–Campanian.
    [Show full text]
  • The Confusion Range, West-Central Utah: Fold-Thrust Deformation and a Western Utah Thrust Belt in the Sevier Hinterland
    The Confusion Range, west-central Utah: Fold-thrust deformation and a western Utah thrust belt in the Sevier hinterland David C. Greene* Department of Geosciences, Denison University, Granville, Ohio 43023, USA ABSTRACT INTRODUCTION tions together while delineating the lateral and oblique thrust ramps that form a signifi cant The Confusion Range in west-central Utah The Confusion Range is a collection of ridges complicating factor in the structure of the fold- has been considered a broad structural trough and small ranges that together form a low moun- thrust system. Together, these fi ve cross sections or synclinorium with little overall shorten- tain range in western Utah, between the more total almost 300 km in map length. Enlarged ing. However, new structural studies indicate imposing Snake Range on the west and House versions of the cross sections at a scale of that the Confusion Range is more accurately Range on the east (Figs. 1 and 2). The range is 1:50,000, along with a discussion of the petro- characterized as an east-vergent, fold-thrust named for its “rugged isolation and confusing leum potential of the region, may be found in system with ~10 km of horizontal shortening topography” (Van Cott, 1990). The Confusion Greene and Herring (2013). during Late Jurassic to Eocene Cordilleran Range exposes ~5000 m of Ordovician through Similar structural style and fold-thrust struc- contractional deformation. For this study, Triassic strata in what has been considered a tures are continuous southward throughout the four balanced and retrodeformable cross broad structural trough or synclinorium (e.g., length of the originally proposed synclinorium, sections across the Confusion Range and Hose, 1977; Anderson, 1983; Hintze and Davis, forming a fold-thrust belt more than 130 km in adjacent Tule Valley were constructed using 2003; Rowley et al., 2009).
    [Show full text]
  • Plate Tectonics
    Plate Tectonics Plate Tectonics is a unifying theory that states that the Earth is composed of lithospheric crustal plates that move slowly, change size, and interact with one another. This theory was amalgamated from a variety of studies that began in the early 20th century and culminated in the 1960s. Early Players: Richard Oldham (1858-1936): discovered P Wave Shadow Zones Inge Lehmann (1888-1993): discovered the S Wave Shadow Zone, including the fact that the outer core is liquid Eduard Suess (1831-1914): published internal structure of the Earth, utilizing some of Oldham’s data Andrija Mohorovicic (1857-1936): discovered the seismic discontinuity between the crust and the mantle Beno Gutenberg (1889-1960): found the CMB to be at 2900 km The Great Synthesizer: Alfred Wagener (1880-1930) Book: The Origin of Continents and Oceans (1915) Found six major pieces of evidence the continents move, hence his theory is known as Continental Drift. (Figures 19.2-1911) 1) The shape of the continents: they fit together 2) Paleontological Evidence: found matching fossils on several continents a) Glossopteris: found in rocks of the same age on South America, South Africa, Australia, India and Antarctica b) Lystrosaurus: found in rocks of the same age on Africa, India, also some in Asia and Antarctica c) Mesosaurus: found in rocks of the same age on South America, South Africa d) Cynognathus: found in rocks of the same age on South America, South Africa 3) Glacial Evidence: the glaciers appear to originate from the modern-day oceans (which is impossible) 4) Structure and Rock Type: geologic features end on one continent and reappear on the other (South America and Africa) 5) Paleoclimate Zones: like today, the old Earth had climate zones.
    [Show full text]
  • Developing the Orogenic Gold Deposit Model: Insights from R&D for Exploration Success
    "Accretionary Wedge Geodynamic Evolution, Metamorphic Equilibria, Metasomatic Processes, & GOLD” by Dave Lentz (UNB) Accretionary ophiolitic sequence (with quartz veins), basement Santorini, Greece 2m Orogenic Gold first used by Bohlke (1982) Developing the Orogenic Gold Deposit Model: Insights from R&D for Exploration Success by Dave Lentz (UNB) Accretionary ophiolitic sequence (with quartz veins), basement Santorini, Greece 2m Orogenic Gold first used by Bohlke (1982) SPONSORS INTRODUCTION PART I: Review Gold Deposit Settings • Historical Evolution of ideas • Description of Orogenic Au Systems • Enigmatic aspects of the metamorphogenic model PART II: Geothermal to Hydrothermal Evolution • Metamorphic Considerations to Thermal Evolution • Fluid Source (and Solubility Implications) PART III: Geodynamic Evolution • Accretionary Geodynamics (to collision) • Structural-Metamorphic Evolution & Settings • Implications for refining the metamorphogenic Orogenic Gold Model PART I: Review Gold Deposit Settings Mineralization in forearc to back arc system Accretionary Wedge fore arc settings Mitchell & Garson (1982) OROGENIC GOLD: Magmatic to Metamorphic hydrothermal continuum Groves et al. (1998) How are Gold Systems Related to Crustal Growth? From Goldfarb (2006) Magmatic-dominated Metamorphic-dominated Groves et al. (1998) Metamorphic,Metamorphic, Transitional,Transitional, andand MagmaticMagmatic GoldGold ModelsModels Poulsen (2000) Metamorphic dominated Setting Juneau Belt Prehnite- Donlin Creek pumpellite Ross Mine Kirkland Lake Dome Brittle Sigma/Giant-Con Greenschist Hollinger-McIntyre Ductile-Brittle Amphibolite Red Lake Eastmain/Lynn Lake Musselwhite Granulite Ductile Lake Lilois Fluid Egress along Advective Crustal-scale Heat n Shear Zone o i t Transfer a n o Z l a t e Zone of deposition M Low salinities (< 3 wt % NaCl, KCl, etc.) Source Region (or deeper) Fyfe & Henley (1973) RETROGRESSION PART II: Geothermal to Hydrothermal Evolution Fluid movement Ethridge et al.
    [Show full text]
  • Download Preprint
    This is a preprint that has no-yet undergone peer-review. Please note that subsequent versions of this manuscript may have different content. We share this preprint to openly share our ongoing work and to generate community discussion; we warmly welcome comments or feedback via email ([email protected]). Rift Flank Erosion & Sediment Routing Paper_____________________________________________________Elliott et al 1 Tectono-stratigraphic development of a salt-influenced rift margin; Halten 2 Terrace, offshore Mid-Norway 3 Gavin M. Elliott*1, Christopher A-L. Jackson1, Robert L. Gawthorpe2, Paul Wilson3,6, 4 5 4 Ian R. Sharp & Lisa Michelsen 5 1 Basin Research Group (BRG), Department of Earth Science & Engineering, Imperial College 6 London, London, UK 7 2 Department of Earth Sciences, University of Bergen, Norway 8 3 Basin Studies & Petroleum Geoscience, SEAES, University of Manchester, Manchester UK 9 4 Equinor Research Centre, Sandsliveien 90, Bergen, Norway 10 5 Equinor ASA, Mølnholtet 42, Harstad, Norway 11 6 Now at: Schlumberger Oilfield UK PLC, Schlumberger House, Gatwick, UK 12 *Corresponding Author Email: [email protected] 13 1. Abstract 14 In salt-influenced rift basins the presence of a pre-rift salt layer will control the 15 tectono-stratigraphic evolution of the rift due to the decoupling of the sub- and supra- 16 salt faults leading to temporal and spatial variations in structural style. Lateral 17 variations in rift flank structure will control the dispersal and volumes of sediment 18 deposited in rifts and along rifted margins, which in turn impacts facies distributions 19 within syn-rift stratigraphic successions. We here use 3D seismic reflection and 20 borehole data to study the tectono-stratigraphic development of the Halten Terrace, 21 offshore Mid-Norway, a salt-influenced rifted margin formed during Middle to Late 22 Jurassic extension.
    [Show full text]
  • Tectonic Features of the Precambrian Belt Basin and Their Influence on Post-Belt Structures
    ... Tectonic Features of the .., Precambrian Belt Basin and Their Influence on Post-Belt Structures GEOLOGICAL SURVEY PROFESSIONAL PAPER 866 · Tectonic Features of the · Precambrian Belt Basin and Their Influence on Post-Belt Structures By JACK E. HARRISON, ALLAN B. GRIGGS, and JOHN D. WELLS GEOLOGICAL SURVEY PROFESSIONAL PAPER X66 U N IT ED STATES G 0 V ERN M EN T P R I NT I N G 0 F F I C E, \VAS H I N G T 0 N 19 7 4 UNITED STATES DEPARTMENT OF THE INTERIOR ROGERS C. B. MORTON, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress catalog-card No. 74-600111 ) For sale by the Superintendent of Documents, U.S. GO\·ernment Printing Office 'Vashington, D.C. 20402 - Price 65 cents (paper cO\·er) Stock Number 2401-02554 CONTENTS Page Page Abstract................................................. 1 Phanerozoic events-Continued Introduction . 1 Late Mesozoic through early Tertiary-Continued Genesis and filling of the Belt basin . 1 Idaho batholith ................................. 7 Is the Belt basin an aulacogen? . 5 Boulder batholith ............................... 8 Precambrian Z events . 5 Northern Montana disturbed belt ................. 8 Phanerozoic events . 5 Tectonics along the Lewis and Clark line .............. 9 Paleozoic through early Mesozoic . 6 Late Cenozoic block faults ........................... 13 Late Mesozoic through early Tertiary . 6 Conclusions ............................................. 13 Kootenay arc and mobile belt . 6 References cited ......................................... 14 ILLUSTRATIONS Page FIGURES 1-4. Maps: 1. Principal basins of sedimentation along the U.S.-Canadian Cordillera during Precambrian Y time (1,600-800 m.y. ago) ............................................................................................... 2 2. Principal tectonic elements of the Belt basin reentrant as inferred from the sedimentation record ............
    [Show full text]
  • Sedimentological Constraints on the Initial Uplift of the West Bogda Mountains in Mid-Permian
    www.nature.com/scientificreports OPEN Sedimentological constraints on the initial uplift of the West Bogda Mountains in Mid-Permian Received: 14 August 2017 Jian Wang1,2, Ying-chang Cao1,2, Xin-tong Wang1, Ke-yu Liu1,3, Zhu-kun Wang1 & Qi-song Xu1 Accepted: 9 January 2018 The Late Paleozoic is considered to be an important stage in the evolution of the Central Asian Orogenic Published: xx xx xxxx Belt (CAOB). The Bogda Mountains, a northeastern branch of the Tianshan Mountains, record the complete Paleozoic history of the Tianshan orogenic belt. The tectonic and sedimentary evolution of the west Bogda area and the timing of initial uplift of the West Bogda Mountains were investigated based on detailed sedimentological study of outcrops, including lithology, sedimentary structures, rock and isotopic compositions and paleocurrent directions. At the end of the Early Permian, the West Bogda Trough was closed and an island arc was formed. The sedimentary and subsidence center of the Middle Permian inherited that of the Early Permian. The west Bogda area became an inherited catchment area, and developed a widespread shallow, deep and then shallow lacustrine succession during the Mid- Permian. At the end of the Mid-Permian, strong intracontinental collision caused the initial uplift of the West Bogda Mountains. Sedimentological evidence further confrmed that the West Bogda Mountains was a rift basin in the Carboniferous-Early Permian, and subsequently entered the Late Paleozoic large- scale intracontinental orogeny in the region. The Central Asia Orogenic Belt (CAOB) is the largest accretionary orogen on Earth, which was formed by the amalgamation of multiple micro-continents, island arcs and accretionary wedges1–5.
    [Show full text]
  • 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).
    [Show full text]