• Login
    About WHOAS
    View Item 
    •   WHOAS Home
    • Woods Hole Oceanographic Institution
    • Geology and Geophysics (G&G)
    • View Item
    •   WHOAS Home
    • Woods Hole Oceanographic Institution
    • Geology and Geophysics (G&G)
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of WHOASCommunities & CollectionsBy Issue DateAuthorsTitlesKeywordsThis CollectionBy Issue DateAuthorsTitlesKeywords

    My Account

    LoginRegister

    Statistics

    View Usage Statistics

    Constraints on the lake volume required for hydro-fracture through ice sheets

    Thumbnail
    View/Open
    Article (462.8Kb)
    Figure S1: Critical crack length for complete ice sheet fracture. (117.8Kb)
    Figure S2: Crack penetration depth, as a function of water content. (1.705Mb)
    Figure S3: Comparison of opening geometries for 2 model calculations, dry versus water-filled. (111.1Kb)
    Figure S4: Mean flux of water through moulins and cracks. (368.5Kb)
    Figure S5: A healed crevasse in the field with dimensions typical for a deep water-filled crack. (47.21Mb)
    Figure S6: An ice canyon which yields a 3-D view of crack geometry, again with opening geometry consistent with a deep water-filled crack. (57.08Mb)
    Additional file information (3.839Kb)
    Text S1: Text and equations outlining our model and field observations. (126.4Kb)
    Text S1: Text and equations outlining our model and field observations. (10.99Kb)
    Date
    2009-05-16
    Author
    Krawczynski, Michael J.  Concept link
    Behn, Mark D.  Concept link
    Das, Sarah B.  Concept link
    Joughin, Ian  Concept link
    Metadata
    Show full item record
    Citable URI
    https://hdl.handle.net/1912/3378
    As published
    https://doi.org/10.1029/2008GL036765
    DOI
    10.1029/2008GL036765
    Keyword
     Supraglacial lakes; Greenland; Hydrofracture 
    Abstract
    Water-filled cracks are an effective mechanism to drive hydro-fractures through thick ice sheets. Crack geometry is therefore critical in assessing whether a supraglacial lake contains a sufficient volume of water to keep a crack water-filled until it reaches the bed. In this study, we investigate fracture propagation using a linear elastic fracture mechanics model to calculate the dimensions of water-filled cracks beneath supraglacial lakes. We find that the cross-sectional area of water-filled cracks increases non-linearly with ice sheet thickness. Using these results, we place volumetric constraints on the amount of water necessary to drive cracks through ∼1 km of sub-freezing ice. For ice sheet regions under little tension, lakes larger than 0.25–0.80 km in diameter contain sufficient water to rapidly drive hydro-fractures through 1–1.5 km of subfreezing ice. This represents ∼98% of the meltwater volume held in supraglacial lakes in the central western margin of the Greenland Ice Sheet.
    Description
    Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 36 (2009): L10501, doi:10.1029/2008GL036765.
    Collections
    • Geology and Geophysics (G&G)
    Suggested Citation
    Geophysical Research Letters 36 (2009): L10501
     
    All Items in WHOAS are protected by original copyright, with all rights reserved, unless otherwise indicated. WHOAS also supports the use of the Creative Commons licenses for original content.
    A service of the MBLWHOI Library | About WHOAS
    Contact Us | Send Feedback | Privacy Policy
    Core Trust Logo