Now showing items 928-947 of 984

  • Ultra-small graphitization reactors for ultra-microscale 14C analysis at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) Facility 

    Shah Walter, Sunita R.; Gagnon, Alan R.; Roberts, Mark L.; McNichol, Ann P.; Lardie Gaylord, Mary C.; Klein, Elizabeth (University of Arizona Libraries, 2015)
    In response to the increasing demand for 14C analysis of samples containing less than 25 µg C, ultra-small graphitization reactors with an internal volume of ~0.8 mL were developed at NOSAMS. For samples containing 6 to ...
  • Ultrastructure and molecular phylogeny of Calkinsia aureus : cellular identity of a novel clade of deep-sea euglenozoans with epibiotic bacteria 

    Yubuki, Naoji; Edgcomb, Virginia P.; Bernhard, Joan M.; Leander, Brian S. (BioMed Central, 2009-01-27)
    The Euglenozoa is a large group of eukaryotic flagellates with diverse modes of nutrition. The group consists of three main subclades – euglenids, kinetoplastids and diplonemids – that have been confirmed with both molecular ...
  • Underplating of the Hawaiian Swell : evidence from teleseismic receiver functions 

    Leahy, Garrett M.; Collins, John A.; Wolfe, Cecily J.; Laske, Gabi; Solomon, Sean C. (John Wiley & Sons, 2010-08-12)
    The Hawaiian Islands are the canonical example of an age-progressive island chain, formed by volcanism long thought to be fed from a hotspot source that is more or less fixed in the mantle. Geophysical data, however, have ...
  • Understanding the role of the biological pump in the global carbon cycle : an imperative for ocean science 

    Honjo, Susumu; Eglinton, Timothy I.; Taylor, Craig D.; Ulmer, Kevin M.; Sievert, Stefan M.; Bracher, Astrid; German, Christopher R.; Edgcomb, Virginia P.; Francois, Roger; Iglesias-Rodriguez, M. Debora; Van Mooy, Benjamin A. S.; Repeta, Daniel J. (The Oceanography Society, 2014-09)
    Anthropogenically driven climate change will rapidly become Earth's dominant transformative influence in the coming decades. The oceanic biological pump—the complex suite of processes that results in the transfer of ...
  • Unraveling the sequence of serpentinization reactions : petrography, mineral chemistry, and petrophysics of serpentinites from MAR 15°N (ODP Leg 209, Site 1274) 

    Bach, Wolfgang; Paulick, Holger; Garrido, Carlos J.; Ildefonse, Benoit; Meurer, William P.; Humphris, Susan E. (American Geophysical Union, 2006-07-06)
    The results of detailed textural, mineral chemical, and petrophysical studies shed new light on the poorly constrained fluid-rock reaction pathways during retrograde serpentinization at mid-ocean ridges. Uniformly depleted ...
  • Upper crustal evolution across the Juan de Fuca ridge flanks 

    Nedimovic, Mladen R.; Carbotte, Suzanne M.; Diebold, John B.; Harding, Alistair J.; Canales, J. Pablo; Kent, Graham M. (American Geophysical Union, 2008-09-30)
    Recent P wave velocity compilations of the oceanic crust indicate that the velocity of the uppermost layer 2A doubles or reaches ∼4.3 km/s found in mature crust in <10 Ma after crustal formation. This velocity change is ...
  • Upper crustal structure and axial topography at intermediate spreading ridges : seismic constraints from the southern Juan de Fuca Ridge 

    Canales, J. Pablo; Detrick, Robert S.; Carbotte, Suzanne M.; Kent, Graham M.; Diebold, John B.; Harding, Alistair J.; Babcock, Jeffrey M.; Nedimovic, Mladen R.; Van Ark, Emily M. (American Geophysical Union, 2005-12-14)
    We use multichannel seismic reflection data to image the upper crustal structure of 0-620 ka crust along the southern Juan de Fuca Ridge (JdFR). The study area comprises two segments spreading at intermediate rate with ...
  • Upper mantle electrical resistivity structure beneath the central Mariana subduction system 

    Matsuno, Tetsuo; Seama, Nobukazu; Evans, Rob L.; Chave, Alan D.; Baba, Kiyoshi; White, Antony; Goto, Tada-nori; Heinson, Graham; Boren, Goran; Yoneda, Asami; Utada, Hisashi (American Geophysical Union, 2010-09-02)
    This paper reports on a magnetotelluric (MT) survey across the central Mariana subduction system, providing a comprehensive electrical resistivity image of the upper mantle to address issues of mantle dynamics in the mantle ...
  • Upper mantle seismic anisotropy at a strike-slip boundary : South Island, New Zealand 

    Zietlow, Daniel W.; Sheehan, Anne F.; Molnar, Peter H.; Savage, Martha K.; Hirth, Greg; Collins, John A.; Hager, Bradford H. (John Wiley & Sons, 2014-02-05)
    New shear wave splitting measurements made from stations onshore and offshore the South Island of New Zealand show a zone of anisotropy 100–200 km wide. Measurements in central South Island and up to approximately 100 km ...
  • Upper ocean oxygenation dynamics from I/Ca ratios during the Cenomanian-Turonian OAE 2 

    Zhou, Xiaoli; Jenkyns, Hugh C.; Owens, Jeremy D.; Junium, Christopher K.; Zheng, Xin-Yuan; Sageman, Bradley B.; Hardisty, Dalton S.; Lyons, Timothy W.; Ridgwell, Andy; Lu, Zunli (John Wiley & Sons, 2015-05-13)
    Global warming lowers the solubility of gases in the ocean and drives an enhanced hydrological cycle with increased nutrient loads delivered to the oceans, leading to increases in organic production, the degradation of ...
  • Uranium-series radionuclide records of paleoceanographic and sedimentary changes in the Arctic Ocean 

    Hoffmann, Sharon S. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2009-02)
    The radionuclides 231Pa and 230Th, produced in the water column and removed from the ocean by particle scavenging and burial in sediments, offer a means for paleoceanographers to examine past dynamics of both water column ...
  • User's guide for FINDIF at SACLANTCEN 

    Stephen, Ralph A. (Woods Hole Oceanographic Institution, 1992-05)
    FINDIF solves the elastic wave equation for a line source in two dimensions by the finite difference method (Virieux,1986; Stephen,1988b). The solution is carried out in the time domain for either pulse or CW sources. ...
  • User's guide for PLOT_FINDIF 

    Bolmer, S. Thompson; Stephen, Ralph A. (Woods Hole Oceanographic Institution, 2006-02)
    PLOT_FINDIF is a MATLAB script which is used to plot output from the Woods Hole Oceanographic Institution (WHOI) Time Domain Finite Difference (TDFD) program called "Geoacoustic_TDFD" Both Geoacoustic_TDFD and PLOT_FINDIF ...
  • A user’s manual for finite difference synthetic seismogram codes on the CYBER 205 and CRAY XMP-12 

    Hunt, Mary M.; Stephen, Ralph A. (Woods Hole Oceanographic Institution, 1986-11)
    Over the past eight years, a software package has been developed to solve the elastic wave equation by the method of finite differences (Hunt et al., 1983; Stephen, 1983; Stephen, 1984a; Stephen, 1984b; Nicoletis, 1981). ...
  • Using CSEM techniques to map the shallow section of seafloor : from the coastline to the edges of the continental slope 

    Evans, Rob L. (Society of Exploration Geophysicists, 2007-03-01)
    Many important processes occur within the shallow section of the seafloor on the continental shelf and slope, yet conventional geophysical constraints on the physical properties within this critical boundary layer are ...
  • Using short-term postseismic displacements to infer the ambient deformation conditions of the upper mantle 

    Freed, Andrew M.; Hirth, Greg; Behn, Mark D. (American Geophysical Union, 2012-01-31)
    To interpret short-term postseismic surface displacements in the context of key ambient conditions (e.g., temperature, pressure, background strain rate, water content, creep mechanism), we combined steady state and transient ...
  • Vailulu'u Seamount, Samoa : life and death on an active submarine volcano 

    Staudigel, Hubert; Hart, Stanley R.; Pile, Adele; Bailey, Bradley E.; Baker, Edward T.; Brooke, Sandra; Connelly, Douglas P.; Haucke, Lisa; German, Christopher R.; Hudson, Ian; Jones, Daniel O. B.; Koppers, Anthony A. P.; Konter, Jasper G.; Lee, Ray; Pietsch, Theodore W.; Tebo, Bradley M.; Templeton, Alexis S.; Zierenberg, Robert; Young, Craig M. (National Academy of Sciences, 2006-04-13)
    Submersible exploration of the Samoan hotspot revealed a new, 300-m-tall, volcanic cone, named Nafanua, in the summit crater of Vailulu'u seamount. Nafanua grew from the 1,000-m-deep crater floor in <4 years and could reach ...
  • Vailulu’u Seamount 

    Koppers, Anthony A. P.; Staudigel, Hubert; Hart, Stanley R.; Young, Craig M.; Konter, Jasper G. (Oceanography Society, 2010-03)
    Vailulu’u seamount is an active underwater volcano that marks the end of the Samoan hotspot trail.
  • Variable crustal structure along the Juan de Fuca Ridge : influence of on-axis hot spots and absolute plate motions 

    Carbotte, Suzanne M.; Nedimovic, Mladen R.; Canales, J. Pablo; Kent, Graham M.; Harding, Alistair J.; Marjanovic, Milena (American Geophysical Union, 2008-08-02)
    Multichannel seismic and bathymetric data from the Juan de Fuca Ridge (JDFR) provide constraints on axial and ridge flank structure for the past 4–8 Ma within three spreading corridors crossing Cleft, Northern Symmetric, ...
  • Variation in styles of rifting in the Gulf of California 

    Lizarralde, Daniel; Axen, Gary J.; Brown, Hillary E.; Fletcher, John M.; Gonzalez-Fernandez, Antonio; Harding, Alistair J.; Holbrook, W. Steven; Kent, Graham M.; Paramo, Pedro; Sutherland, Fiona; Umhoefer, Paul J. (2007-06-18)
    The rifting of continental lithosphere is a fundamental solid-earth process that leads to the formation of rifted continental margins and ocean basins. Understanding of this process comes from observations of the geometry ...