• Login
    View Item 
    •   Home
    • UA Faculty Research
    • UA Faculty Publications
    • View Item
    •   Home
    • UA Faculty Research
    • UA Faculty Publications
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Intracontinental subduction beneath the Pamir Mountains: Constraints from thermokinematic modeling of shortening in the Tajik fold-and-thrust belt

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    B31730_final_version.pdf
    Size:
    6.602Mb
    Format:
    PDF
    Description:
    Final Accepted Manuscript
    Download
    Author
    Chapman, James B. cc
    Carrapa, Barbara
    Ballato, Paolo
    DeCelles, Peter G. cc
    Worthington, James
    Oimahmadov, Ilhomjon
    Gadoev, Mustafo cc
    Ketcham, Richard
    Affiliation
    Univ Arizona, Dept Geosci
    Issue Date
    2017
    
    Metadata
    Show full item record
    Publisher
    GEOLOGICAL SOC AMER, INC
    Citation
    James B. Chapman, Barbara Carrapa, Paolo Ballato, Peter G. DeCelles, James Worthington, Ilhomjon Oimahmadov, Mustafo Gadoev, Richard Ketcham; Intracontinental subduction beneath the Pamir Mountains: Constraints from thermokinematic modeling of shortening in the Tajik fold-and-thrust belt. GSA Bulletin ; 129 (11-12): 1450–1471. doi: https://doi.org/10.1130/B31730.1
    Journal
    GEOLOGICAL SOCIETY OF AMERICA BULLETIN
    Rights
    © 2017 Geological Society of America.
    Collection Information
    This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.
    Abstract
    A regional, balanced cross section is presented for the thin-skinned Tajik fold-and-thrust belt, constrained by new structural and stratigraphic data, industrial well-log data, flexural modeling, and existing geologic and geophysical mapping. A sequential restoration of the section was calibrated with 15 new apatite (U-Th)/He ages and 7 new apatite fission-track ages from samples of the major thrust sheets within the Tajik fold-and-thrust belt. Thermokinematic modeling indicates that deformation in the Tajik fold-and-thrust belt began during the Miocene (prior to or ca. 17 Ma) and continues to near present, with long-term shortening rates of similar to 4-6 mm/yr and Pliocene to present rates of similar to 6-8 mm/yr. The Tajik fold-and-thrust belt can be characterized as two distinct, oppositely verging thrust belts. Deformation initiated at opposite margins of the Tajik foreland basin, adjacent the southwest Tian Shan and northwest Pamir Mountains, and propagated toward the center of the basin, eventually incorporating the foreland basin entirely into a composite fold-and-thrust belt. The western Tajik fold-and-thrust belt records at least 35-40 km of total shortening and is part of the greater Tian Shan orogenic system. The eastern Tajik fold-and-thrust belt records similar to 30 km of shortening linked to the Pamir Mountains. The amount of shortening in the Tajik fold-and-thrust belt is significantly less than predicted by models of intracontinental subduction, which call for subduction of an similar to 300-km-long slab of continental Tajik-Tarim lithosphere beneath the Pamir. Field observations and structural relationships suggest that the Mesozoic and younger sedimentary rocks of the Tajik Basin were deposited on and across the Northern Pamir terrane and then subsequently uplifted and eroded during orogenic growth, rather than undergoing subduction beneath the Pamir. The Paleozoic-Proterozoic(?) metasedimentary and igneous rocks exposed in the Northern Pamir terrane are equivalent to the middle-lower crust of the Tajik Basin, which has become incorporated into the Pamir orogen. We propose that the southdipping zone of deep seismicity beneath the Pamir, which is the basis for the intra-continental subduction model, is related to gravitational foundering (by delamination or large-scale dripping) of Pamir lower crust and mantle lithosphere. This contrasts with previous models that related the Pamir seismic zone to subduction with or without roll-back of Asian lithosphere. Delamination may explain the initiation of extension in the Pamir gneiss domes and does not require a change in plate boundary forces to switch between compressional and extensional regimes. Because the Pamir is the archetype for active subduction of continental lithosphere in the interior of continental plates (intracontinental subduction), the viability of this particular tectonic process may need to be reassessed.
    Note
    12 month embargo; published online: 30 June 2017
    ISSN
    0016-7606
    DOI
    10.1130/B31730.1
    Version
    Final accepted manuscript
    Sponsors
    American Philosophical Society; American Association of Petroleum Geologists; Geological Society of America; Exxon Mobil Corporation
    Additional Links
    http://pubs.geoscienceworld.org/gsabulletin/article/doi/10.1130/B31730.1/208082/Intracontinental-subduction-beneath-the-Pamir
    ae974a485f413a2113503eed53cd6c53
    10.1130/B31730.1
    Scopus Count
    Collections
    UA Faculty Publications

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.