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Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01

Description: The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity,… more
Date: June 30, 2011
Creator: Trehu, Anne & Kannberg, Peter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Site Selection for DOE/JIP Gas Hydrate Drilling in the Northern Gulf of Mexico

Description: Studies of geologic and geophysical data from the offshore of India have revealed two geologically distinct areas with inferred gas hydrate occurrences: the passive continental margins of the Indian Peninsula and along the Andaman convergent margin. The Indian National Gas Hydrate Program (NGHP) Expedition 01 was designed to study the occurrence of gas hydrate off the Indian Peninsula and along the Andaman convergent margin with special emphasis on understanding the geologic and geochemical con… more
Date: July 1, 2008
Creator: Collett, T. S.; Riedel, M.; Cochran, J. R.; Boswell, R. M.; Kumar, Pushpendra & Sathe, A. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The continental margin is a key source of iron to the HNLC North Pacific Ocean

Description: Here we show that labile particulate iron and manganese concentrations in the upper 500m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima between 100-200 m, reaching 3 nM and 600 pM, respectively. The subsurface concentration maxima in particulate Fe are characterized by a more reduced oxidation state, suggesting a source from primary volcagenic minerals such as from the Kuril/Kamchatka margin. The systematics of the… more
Date: January 15, 2008
Creator: Lam, P. J. & Bishop, J. K. B
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Molecular Approaches to Understanding C & N Dynamics in Marine Sediments

Description: Continental margin sediments constitute only about 10% of the total sediment surface area in the world’s oceans, nevertheless they are the dominant sites of nitrogen (N) cycling. Recent studies suggest that the oceanic nitrogen budget is unbalanced, primarily due to a higher nitrogen removal rate in contrast to the fixation rate, and it has been suggested that denitrification activity contributes significantly to this imbalance. Although denitrification in marine environments has been studied i… more
Date: May 16, 2007
Creator: Massol, Arturo; Tiedje, James; Zhou, Jizhong & Devol, Allan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: Cooperative Agreement DE-FC26-01NT41329 between Joint Oceanographic Institutions and DOE-NETL was divided into two phases based on successive proposals and negotiated statements of work pertaining to activities to sample and characterize methane hydrates on ODP Leg 204 (Phase 1) and on IODP Expedition 311 (Phase 2). The Phase 1 Final Report was submitted to DOE-NETL in April 2004. This report is the Phase 2 Final Report to DOE-NETL. The primary objectives of Phase 2 were to sample and character… more
Date: September 20, 2006
Creator: Rack, Frank R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wintertime pytoplankton bloom in the Subarctic Pacific supportedby continental margin iron

Description: Heightened biological activity was observed in February 1996in the high-nutrient low-chlorophyll (HNLC) subarctic North PacificOcean, a region that is thought to beiron-limited. Here we provideevidence supporting the hypothesis that Ocean Station Papa (OSP) in thesubarctic Pacific received a lateral supply of particulate iron from thecontinental margin off the Aleutian Islands in the winter, coincidentwith the observed biological bloom. Synchrotron X-ray analysis was usedto describe the physica… more
Date: June 8, 2004
Creator: Lam, Phoebe J.; Bishop, James K.B.; Henning, Cara C.; Marcus,Matthew A.; Waychunas, Glenn A. & Fung, Inez
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishment of the JOI Cooperative Agreement with DOE/NETL in this quarter was the deployment of tools and measurement systems on ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September, 2002. During Leg 204, we cored and logged 9 sites on the Oregon continental margin to determine the distribution and concentration of gas hydrates in an accretionary ridge and adjacent slope basin, investigate the mechanisms that transport methane and o… more
Date: September 30, 2002
Creator: Rack, Frank; Bohrmann, Gerhard; Trehu, Anne; Storms, Michael; Schroeder, Derryl & Party, ODP Leg 204 Shipboard Scientific
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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X-ray Scanner for ODP Leg 204: Drilling Gas Hydrates on Hydrate Ridge, Cascadia Continental Margin

Description: An x-ray scanner was designed and fabricated at Lawrence Berkeley National Laboratory to provide high speed acquisition of x-ray images of sediment cores collected on the Ocean Drilling Program (ODP) Leg 204: Drilling Gas Hydrates On Hydrate Ridge, Cascadia Continental Margin. This report discusses the design and fabrication of the instrument, detailing novel features that help reduce the weight and increase the portability of the instrument. Sample x-ray images are included. The x-ray scanner … more
Date: August 8, 2002
Creator: Freifeld, Barry; Kneafsey, Tim; Pruess, Jacob; Reiter, Paul & Tomutsa, Liviu
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Methane Hydrates: Major Energy Source for the Future or Wishful Thinking?

Description: Methane hydrates are methane bearing, ice-like materials that occur in abundance in permafrost areas such as on the North Slope of Alaska and Canada and as well as in offshore continental margin environments throughout the world including the Gulf of Mexico and the East and West Coasts of the United States. Methane hydrate accumulations in the United States are currently estimated to be about 200,000 Tcf, which is enormous when compared to the conventional recoverable resource estimate of 2300 … more
Date: September 1, 2001
Creator: Thomas, Charles Phillip
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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T-Phase Observations from the May 1999 Ascension Island Experiment

Description: The Comprehensive Nuclear-Test-Ban Treaty (CTBT) specifies that an International Monitoring System (IMS) will be used to detect and locate disturbances that could be related to nuclear testing. In order to monitor disturbances in and near the world's oceans, the IMS will rely on a network of 11 hydroacoustic stations. This hydroacoustic network will be composed of 6 hydrophone stations and 5 T-phase seismic stations. The hydrophone stations will record pressure variations in the ocean. The T-ph… more
Date: July 19, 2000
Creator: Rodgers, A & Harben, P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling the conversion of hydroacoustic to seismic energy at island and continental margins: preliminary analysis of Ascension Island data

Description: Seismic stations at islands and continental margins will be an essential component of the International Monitoring System (IMS) for event location and identification in support of Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring. Particularly important will be the detection and analysis of hydroacoustic-to-seismic converted waves (T-phases) at island or continental margins. Acoustic waves generated by sources in or near the ocean propagate for long distances very efficiently due to the o… more
Date: July 26, 1999
Creator: Harben, P. & Rodgers, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Roles of Advection and In Situ Growth in Determining the Dynamics of Continental Shelf Zooplankton: High Frequency Measurements of Zooplankton Biomass Coupled with Measurements of Secondary Productivity in the Middle Atlantic Bight

Description: Evaluation of the role of continental margins in planetary carbon cycles can be approached in various ways, with the extremes being knowledge generated either by large-scale studies of a few basic characteristics of the carbon cycle of shelves worldwide (comparative approach) or by temporally intensive studies of a few sites selected to typify contrasting processes. Mechanisms of cross-shelf transfer, for example, are presently of great interest and within the US there are at least four differi… more
Date: March 26, 1999
Creator: Smith, Sharon L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surficial bioturbation and rapid benthic remineralization in the Cape Hatteras shelf/slope region. Final report

Description: This is a final report for the DOE of grant DE-FG02-92ER61464 ''Surficial bioturbation and rapid benthic remineralization in the Cape Hatteras shelf slope region''. Over the past 6 years we have participated in a multidisciplinary field study called the Ocean margins Program (OMP) to examine the importance of continental margins in the global carbon cycle. Specifically, we have focused on the southern portion of the Mid-Atlantic Bight between Cape Hatteras and Chesapeake Bay where a large flux … more
Date: March 17, 1999
Creator: Aller, Robert C.; Aller, Josephine Y.; Lee, C. & Cochran, J. Kirk
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sea floor cycling of organic matter in the continental margin of the mid-Atlantic Bight. Final report, May 1, 1995--April 30, 1998

Description: The objective of this project was to examine quantitatively the cycling of organic matter at the sea floor of the mid-Atlantic Bight continental margin. This information would be used to better understand sedimentary geochemical processes and, when used in conjunction with other measurements made within the DOE Ocean Margins Program, would be used to constrain the offshore and surface-to-deep water transport of organic carbon in this region. The latter information is critical in assessing the r… more
Date: December 31, 1998
Creator: Jahnke, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development, field testing of a laser instrument for the measurement of sediment reference concentration in the MARGINS Program. Final report

Description: A small grant was added to an ongoing Navy program to extend the scope of ongoing work by development of a new laser instrument. The instrument, MSCAT (Miniature Scattering and Transmissometry) uses small angle scattering to obtain the needed multi-parameter information for measurement of particle size distribution and number density. During the short course of the grant, the instrument was built and tested in a field experiment off the coast of North Carolina. Useful data were obtained, and th… more
Date: May 22, 1998
Creator: Agrawal, Yogesh C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical assessment of large marine particles: Development of an imaging and analysis system for quantifying large particle distributions and fluxes. Final report, June 1992--May 1996

Description: The central goal of DOE`s Ocean Margin Program (OMP) has been to determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or exporting it to the open ocean. The overall objective of this work within OMP was to develop an instrument package to measure the large aggregate population of particles in the shelf/slope environment at a rate sufficient to integrate the observed particle distributions int… more
Date: April 1, 1997
Creator: Walsh, I. D. & Gardner, W. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Origins and fates of DOM along the New England continental margin. Technical progress report, Year 2

Description: In year two, the authors have analyzed DOM (dissolved organic matter) samples from the Atlantic and Pacific Oceans, performed preliminary experiments concerning the decomposition of DOM, and continued methodological development work for measuring DOM isotopic contents. The year three plans are to finish the methods development, and use samples from two upcoming cruises to characterize the cycling of dissolved organic matter along the eastern US seaboard. A brief summary of the year two activiti… more
Date: June 1, 1994
Creator: Fry, B.; Hopkinson, C. & Altabet, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gas hydrate detection and mapping on the US east coast

Description: Project objectives are to identify and map gas hydrate accumulations on the US eastern continental margin using remote sensing (seismic profiling) techniques and to relate these concentrations to the geological factors that-control them. In order to test the remote sensing methods, gas hydrate-cemented sediments will be tested in the laboratory and an effort will be made to perform similar physical tests on natural hydrate-cemented sediments from the study area. Gas hydrate potentially may repr… more
Date: December 31, 1993
Creator: Ahlbrandt, T. S. & Dillon, W. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Origins and fates of DOM along the New England continental margin. Techical progress report, Year 1

Description: We have focused on methods development and completed an initial survey of Dissolved Organic Matter (DOM) concentration and isotopic composition during the 1994 spring bloom on Georges Bank. The methods development phase assures that high quality measurements will be made in years 2 and 3, and emphasizes developing two independent methods for DON determination. The survey work on Georges Bank will be extended in years 2 and 3 to determine seasonal and spatial changes in DOM concentrations and is… more
Date: June 1, 1993
Creator: Fry, B.; Hopkinson, C. & Altabet, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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