• 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

    Causes and consequences of diachronous V-shaped ridges in the North Atlantic Ocean

    Thumbnail
    View/Open
    Parnell-Turner_et_al-2017-Journal_of_Geophysical_Research__Solid_Earth.pdf (7.854Mb)
    Date
    2017-11-14
    Author
    Parnell-Turner, Ross  Concept link
    White, Nicky  Concept link
    Henstock, Timothy J.  Concept link
    Jones, Stephen M.  Concept link
    Maclennan, John  Concept link
    Murton, Bramley J.  Concept link
    Metadata
    Show full item record
    Citable URI
    https://hdl.handle.net/1912/9506
    As published
    https://doi.org/10.1002/2017JB014225
    DOI
    10.1002/2017JB014225
    Keyword
     Iceland plume; V-shaped ridges; Mantle convection; Oceanic crust 
    Abstract
    In the North Atlantic Ocean, the geometry of diachronous V-shaped features that straddle the Reykjanes Ridge is often attributed to thermal pulses which advect away from the center of the Iceland plume. Recently, two alternative hypotheses have been proposed: rift propagation and buoyant mantle upwelling. Here we evaluate these different proposals using basin-wide geophysical and geochemical observations. The centerpiece of our analysis is a pair of seismic reflection profiles oriented parallel to flow lines that span the North Atlantic Ocean. V-shaped ridges and troughs are mapped on both Neogene and Paleogene oceanic crust, enabling a detailed chronology of activity to be established for the last 50 million years. Estimates of the cumulative horizontal displacement across normal faults help to discriminate between brittle and magmatic modes of plate separation, suggesting that crustal architecture is sensitive to the changing planform of the plume. Water-loaded residual depth measurements are used to estimate crustal thickness and to infer mantle potential temperature which varies by ±25°C on timescales of 3–8 Ma. This variation is consistent with the range of temperatures inferred from geochemical modeling of dredged basaltic rocks along the ridge axis itself, from changes in Neogene deep-water circulation, and from the regional record of episodic Cenozoic magmatism. We conclude that radial propagation of transient thermal anomalies within an asthenospheric channel that is 150 ± 50 km thick best accounts for the available geophysical and geochemical observations.
    Description
    Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of [publisher] for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 122 (2017): 8675–8708, doi:10.1002/2017JB014225.
    Collections
    • Geology and Geophysics (G&G)
    Suggested Citation
    Journal of Geophysical Research: Solid Earth 122 (2017): 8675–8708
     

    Related items

    Showing items related by title, author, creator and subject.

    • Thumbnail

      The role of external inputs and internal cycling in shaping the global ocean cobalt distribution : insights from the first cobalt biogeochemical model 

      Tagliabue, Alessandro; Hawco, Nicholas J.; Bundy, Randelle M.; Landing, William M.; Milne, Angela; Morton, Peter L.; Saito, Mak A. (John Wiley & Sons, 2018-04-16)
      Cobalt is an important micronutrient for ocean microbes as it is present in vitamin B12 and is a co‐factor in various metalloenzymes that catalyze cellular processes. Moreover, when seawater availability of cobalt is ...
    • Thumbnail

      The shape of the oceanic nitracline 

      Omand, Melissa M.; Mahadevan, Amala (Copernicus Publications on behalf of the European Geosciences Union, 2015-06-03)
      In most regions of the ocean, nitrate is depleted near the surface by phytoplankton consumption and increases with depth, exhibiting a strong vertical gradient in the pycnocline (here referred to as the nitracline). The ...
    • Thumbnail

      Body shape changes associated with reproductive status, nutritive condition and growth in right whales Eubalaena glacialis and E. australis 

      Miller, Carolyn A.; Best, Peter B.; Perryman, Wayne L.; Baumgartner, Mark F.; Moore, Michael J. (Inter-Research, 2012-07-12)
      Mammalian reproduction is metabolically regulated; therefore, the endangered status and high variability in reproduction of North Atlantic right whales Eubalaena glacialis necessitate accurate assessments at sea of the ...
    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