Now showing items 675-694 of 1059

    • Ocean Seismic Network Pilot Experiment 

      Stephen, Ralph A.; Spiess, Fred N.; Collins, John A.; Hildebrand, John A.; Orcutt, John A.; Peal, Kenneth R.; Vernon, Frank L.; Wooding, Frank B. (2003-10-31)
      The primary goal of the Ocean Seismic Network Pilot Experiment (OSNPE) was to learn how to make high quality broadband seismic measurements on the ocean bottom in preparation for a permanent ocean seismic network. The ...
    • Oceanic evidence of climate change in southern Australia over the last three centuries 

      Thresher, Ronald E.; Rintoul, Stephen R.; Koslow, J. Anthony; Weidman, Christopher R.; Adkins, Jess F.; Proctor, Craig (American Geophysical Union, 2004-04-13)
      Chemical analysis of deepwater octocorals collected at 1000 m depth off southern Australia indicates long-term cooling, beginning in the mid-18th century. This cooling appears to reflect shoaling of isotherms along the ...
    • Oceanic lithosphere magnetization : marine magnetic investigations of crustal accretion and tectonic processes in mid-ocean ridge environments 

      Williams, Clare M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2007-09)
      The origin of symmetric alternating magnetic polarity stripes on the seafloor is investigated in two marine environments; along the ridge axis of the fast spreading East Pacific Rise (EPR) (9º 25’-9º 55’N) and at Kane ...
    • Oceanography : oxygen and climate dynamics 

      Doney, Scott C.; Karnauskas, Kristopher B. (Nature Publishing Group, 2014-09)
      Low oxygen levels in tropical oceans shape marine ecosystems and biogeochemistry with climate change expected to expand these regions. Now, a study indicates that regional dynamics control trop ...
    • Olivine friction at the base of oceanic seismogenic zones 

      Boettcher, Margaret S.; Hirth, Greg; Evans, Brian (American Geophysical Union, 2007-01-31)
      We investigate the strength and frictional behavior of olivine aggregates at temperatures and effective confining pressures similar to those at the base of the seismogenic zone on a typical ridge transform fault. Triaxial ...
    • On the Abyssal circulation in the glacial Atlantic 

      Marchal, Olivier; Curry, William B. (American Meteorological Society, 2008-09)
      An inverse method is used to evaluate the information contained in sediment data for the Atlantic basin during the Last Glacial Maximum (defined here as the time interval 18–21 kyr before present). The data being considered ...
    • On the movements of the North Atlantic Subpolar Front in the preinstrumental past 

      Marchal, Olivier; Waelbroeck, Claire; Colin de Verdiere, Alain (American Meteorological Society, 2016-02-19)
      Three sediment records of sea surface temperature (SST) are analyzed that originate from distant locations in the North Atlantic, have centennial-to-multicentennial resolution, are based on the same reconstruction method ...
    • On the observability of oceanic gyres 

      Marchal, Olivier (American Meteorological Society, 2014-09)
      This study examines the observability of a stratified ocean in a square flat basin on a midlatitude beta plane. Here, “observability” means the ability to establish, in a finite interval of time, the time-dependent ocean ...
    • ONR seafloor natural laboratories on slow- and fast-spreading mid-ocean ridges 

      Tucholke, Brian E.; Macdonald, Ken C.; Fox, Paul J. (American Geophysical Union, 1991-06-18)
      Long-term Natural Laboratories for in-depth studies of the seafloor at both a slowspreading (<30 mm/yr) and a fast-spreading (>60 mm/yr) mid-ocean ridge are being established by the Office of Naval Research. The two Natural ...
    • Optimizing a microwave gas ion source for continuous-flow accelerator mass spectrometry 

      von Reden, Karl F.; Roberts, Mark L.; Burton, Joshua R.; Beaupre, Steven R. (2011-09)
      A 2.45 GHz microwave ion source coupled with a magnesium charge exchange canal (CxC) has been successfully adapted to a large acceptance radiocarbon accelerator mass spectrometry system at the National Ocean Sciences AMS ...
    • Optimum and standard beam widths for numerical modeling of interface scattering problems 

      Stephen, Ralph A. (Acoustical Society of America, 2000-03)
      Gaussian beams provide a useful insonifying field for surface or interface scattering problems such as encountered in electromagnetics, acoustics and seismology. Gaussian beams have these advantages: (i) They give a finite ...
    • Options for radioactive and other hazardous waste siting within the U. S. Exclusive Economic Zone 

      Manheim, Frank T.; Vine, Allyn C. (Woods Hole Oceanographic Institution, 1987-03)
      Some areas of the E.E.Z. (Exclusive Economic Zone) offer technical, political and economic options that may complement existing approaches to hazardous waste storage and disposal.
    • Organic phosphorus in marine sediments : chemical structure, diagenetic alteration, and mechanisms of preservation 

      Laarkamp, Kirsten L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2000-09)
      Phosphorus, an essential nutrient, is removed from the oceans only through burial with marine sediments. Organic phosphorus (Porg) constitutes an important fraction (ca. 25%) of total-P in marine sediments. However, given ...
    • Origin and significance of the Delaney Dome Formation, Connemara, Ireland 

      Draut, Amy E.; Clift, Peter D. (Geological Society of London, 2002)
      Dalradian meta-sediments of the Laurentian margin and mafic intrusions thereof in SW Connemara, Ireland, tectonically overlie meta-rhyolites of the Delaney Dome Formation. The two units are separated by the Mannin Thrust. ...
    • The origin and tectonic history of the Southwest Philippine Sea 

      Louden, Keith E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1976-09)
      This thesis is a collection and analysis of seafloor magnetic anomalies, bathymetry, and the paleomagnetism of DSDP sediments and basalt in the West Philippine Basin, in an attempt to resolve questions about its origin ...
    • The origin of HIMU in the SW Pacific : evidence from intraplate volcanism in southern New Zealand and subantarctic islands 

      Panter, Kurt S.; Blusztajn, Jerzy S.; Hart, Stanley R.; Kyle, K. R.; Esser, R.; McIntosh, William C. (2006-02-17)
      This paper presents field, geochemical and isotopic (Sr, Nd, Pb) results on basalts from the Antipodes, Campbell and Chatham Islands, New Zealand. New 40Ar/39Ar age determinations along with previous K-Ar dates reveal three ...
    • The origin of the 1500-year climate cycles in Holocene North-Atlantic records 

      Debret, M.; Bout-Roumazeilles, V.; Grousset, F.; Desmet, M.; McManus, Jerry F.; Massei, N.; Sebag, D.; Petit, J.-R.; Copard, Y.; Trentesaux, A. (Copernicus Publications on behalf of the European Geosciences Union, 2007-10-01)
      Since the first suggestion of 1500-year cycles in the advance and retreat of glaciers (Denton and Karlen, 1973), many studies have uncovered evidence of repeated climate oscillations of 2500, 1500, and 1000 years. During ...
    • Origin of the deep Bering Sea nitrate deficit : constraints from the nitrogen and oxygen isotopic composition of water column nitrate and benthic nitrate fluxes 

      Lehmann, Moritz F.; Sigman, Daniel M.; McCorkle, Daniel C.; Brunelle, Brigitte G.; Hoffmann, Sharon S.; Kienast, Markus; Cane, Greg; Clement, Jaclyn (American Geophysical Union, 2005-10-12)
      On the basis of the normalization to phosphate, a significant amount of nitrate is missing from the deep Bering Sea (BS). Benthic denitrification has been suggested previously to be the dominant cause for the BS nitrate ...
    • The origin of the ninetyeast ridge and the northward motion of India, based on DSDP paleolatitudes 

      Peirce, John Wentworth (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1977-01)
      This thes is is a collection of papers on the paleomagnetics of samples from several Deep Sea Drilling Project (DSDP) sites in the Indian Ocean. These papers present the basic paleomagnetic data, discuss the statistical ...
    • Origin of the smooth zone in early Cretaceous North Atlantic magnetic anomalies 

      Tominaga, Masako; Sager, William W. (American Geophysical Union, 2010-01-06)
      Late Jurassic-Early Cretaceous marine magnetic anomalies observed in the North Atlantic exhibit an abrupt change in character in M5-M15 crust. The anomalies are smoother with low amplitudes, and are difficult to correlate ...