• Login
    View Item 
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Geosciences
    • View Item
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Geosciences
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Scholarworks@UACommunitiesPublication DateAuthorsTitlesSubjectsTypeThis CollectionPublication DateAuthorsTitlesSubjectsType

    My Account

    Login

    First Time Submitters, Register Here

    Register

    Statistics

    Display statistics

    Geology of the boundary area, Eagle A-1 and Tanacross D-1 quadrangles, east-central Alaska

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Flynn_R_2003.pdf
    Size:
    247.7Mb
    Format:
    PDF
    Download
    Author
    Flynn, Roy L.
    Metadata
    Show full item record
    URI
    http://hdl.handle.net/11122/6279
    Abstract
    Structural relationships and tectonic events in the Boundary area of east-central Alaska shed light on the generally obscure tectonic history of the Yukon-Tanana Upland region. This study used detailed mapping of 160 km², with supporting petrography, geochemical analyses, and ⁴⁰Ar/³⁹Ar dating to define the geology and tectonic history of the Boundary area. A major thrust zone juxtaposes lithotectonic assemblages of metamorphic rocks in the Boundary area, with the Fortymile River assemblage (approximately middle amphibolite facies) thrust over the Nasina and Klondike series (middle to upper greenschist facies), and ultramafic rocks and metagabbro (lower greenschist facies) and epidote-amphibolite-facies gneiss and schist imbricated along the thrust faults. Final thrust imbrication postdates cooling from peak metamorphism in amphibolite-facies lithologies, which appears to be Early Jurassic age. The thrust zone is exposed partially rimming a broad, dome-shaped anticline that encompasses the entire map area. Thermally reset ⁴⁰Ar/³⁹Ar ages in the Boundary area appear to be the result of a short-lived, probably igneous, Mid-Cretaceous reheating event, with widespread and locally variable effects, contemporaneous with intrusion of the Crag Mountain pluton south of the map area. Numerous later high-angle, presumably strike-slip faults transect the Boundary area, with apparently associated latest Cretaceous to Miocene volcanic rocks.
    Description
    Thesis (M.S.) University of Alaska Fairbanks, 2003
    Date
    2003-05
    Type
    Thesis
    Collections
    Geosciences

    entitlement

     
    ABOUT US|HELP|BROWSE|ADVANCED SEARCH

    The University of Alaska Fairbanks is an affirmative action/equal opportunity employer and educational institution and is a part of the University of Alaska system.

    ©UAF 2013 - 2023 | Questions? ua-scholarworks@alaska.edu | Last modified: September 25, 2019

    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.