• Login
    View Item 
    •   Home
    • Journals and Magazines
    • Meteoritics & Planetary Science
    • Meteoritics & Planetary Science, Volume 43 (2008)
    • Meteoritics & Planetary Science, Volume 43, Number 12 (2008)
    • View Item
    •   Home
    • Journals and Magazines
    • Meteoritics & Planetary Science
    • Meteoritics & Planetary Science, Volume 43 (2008)
    • Meteoritics & Planetary Science, Volume 43, Number 12 (2008)
    • 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

    Textural constraints on the formation of impact spherules: A case study from the Dales Gorge BIF, Paleoproterozoic Hamersley Group of Western Australia

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    15668-18021-1-PB.pdf
    Size:
    9.932Mb
    Format:
    PDF
    Download
    Author
    Sweeney, D.
    Simonson, B. M.
    Issue Date
    2008-01-01
    Keywords
    microtektites
    impact ejecta
    impact processes
    
    Metadata
    Show full item record
    Citation
    Sweeney, D., & Simonson, B. M. (2008). Textural constraints on the formation of impact spherules: A case study from the Dales Gorge BIF, Paleoproterozoic Hamersley Group of Western Australia. Meteoritics & Planetary Science, 43(12), 2073-2087.
    Publisher
    The Meteoritical Society
    Journal
    Meteoritics & Planetary Science
    URI
    http://hdl.handle.net/10150/656509
    DOI
    10.1111/j.1945-5100.2008.tb00662.x
    Additional Links
    https://meteoritical.org/
    Abstract
    Impact ejecta (about 2.5 Gyr old) in the DS4 layer of the Dales Gorge BIF (Hamersley Group, Western Australia) are so well preserved that many original textures such as vesicles and microlites are faithfully preserved. About 65% of the particles in the layer originated as impact ejecta, of which 81% are splash forms. The remaining 19% are angular, but the splash forms and angular particles have the same composition (mainly diagenetic stilpnomelane and K-feldspar) and share a common suite of internal textures. Some particles contain randomly oriented microlites texturally identical to plagioclase in basalts. Most splash forms have rims of inward-growing crystals that may have formed from the melt (perhaps nucleated by impinging dust) or via thermal devitrification. The rims clearly formed in flight because in broken particles (which make up about 13% of the splash forms) they are generally not present on broken surfaces. The origin of the angular particles is uncertain, but they may represent solid ejecta. Given the large sizes and variable shapes of the splash forms, they are probably droplets of impact melt emplaced ballistically. This is largely by analogy to the K-T boundary layer, but DS4 splash forms differ from K-T spherules in important ways suggesting the K-T model is not universal. The occurrence of basaltic ejecta from a large impact highlights its scarcity in the stratigraphic record despite the areal abundance of oceanic crust. The diverse textures formed via in-flight crystallization suggest particle paths in the plume are more complex than is generally appreciated.
    Type
    Article
    text
    Language
    en
    ISSN
    1945-5100
    ae974a485f413a2113503eed53cd6c53
    10.1111/j.1945-5100.2008.tb00662.x
    Scopus Count
    Collections
    Meteoritics & Planetary Science, Volume 43, Number 12 (2008)

    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.