159 Matching Results

Search Results

Advanced search parameters have been applied.

Laboratory measurements of compressional and shear wave speeds through methane hydrate

Description: Simultaneous measurements of compressional and shear wave speeds through polycrystalline methane hydrate have been made. Methane hydrate, grown directly in a wave speed measurement chamber, was uniaxially compacted to a final porosity below 2%. At 277 K, the compacted material's compressional wave speed was 3650 {+-} 50 m/s. The shear wave speed, measured simultaneously, was 1890 {+-} 30 m/s. From these wave speed measurements, we derive Vp/Vs, Poisson's Ratio, bulk, shear and Young's moduli.
Date: October 25, 1999
Creator: Durham, W B; Waite, WF; Pinkston, J C; Stern, L A; Kirby, S H; Helgerud, M B et al.
Partner: UNT Libraries Government Documents Department

Contribution of oceanic gas hydrate dissociation to the formation of Arctic Ocean methane plumes

Description: Vast quantities of methane are trapped in oceanic hydrate deposits, and there is concern that a rise in the ocean temperature will induce dissociation of these hydrate accumulations, potentially releasing large amounts of carbon into the atmosphere. Because methane is a powerful greenhouse gas, such a release could have dramatic climatic consequences. The recent discovery of active methane gas venting along the landward limit of the gas hydrate stability zone (GHSZ) on the shallow continental slope (150 m - 400 m) west of Svalbard suggests that this process may already have begun, but the source of the methane has not yet been determined. This study performs 2-D simulations of hydrate dissociation in conditions representative of the Arctic Ocean margin to assess whether such hydrates could contribute to the observed gas release. The results show that shallow, low-saturation hydrate deposits, if subjected to recently observed or future predicted temperature changes at the seafloor, can release quantities of methane at the magnitudes similar to what has been observed, and that the releases will be localized near the landward limit of the GHSZ. Both gradual and rapid warming is simulated, along with a parametric sensitivity analysis, and localized gas release is observed for most of the cases. These results resemble the recently published observations and strongly suggest that hydrate dissociation and methane release as a result of climate change may be a real phenomenon, that it could occur on decadal timescales, and that it already may be occurring.
Date: June 1, 2011
Creator: Reagan, M.; Moridis, G.; Elliott, S. & Maltrud, M.
Partner: UNT Libraries Government Documents Department

Basin scale assessment of gas hydrate dissociation in response to climate change

Description: Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating climate. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those now occurring in the arctic and those predicted under future climate change scenarios, has only recently been investigated. Field investigations have discovered substantial methane gas plumes exiting the seafloor along the Arctic Ocean margin, and the plumes appear at depths corresponding to the upper limit of a receding gas hydrate stability zone. It has been suggested that these plumes may be the first visible signs of the dissociation of shallow hydrate deposits due to ongoing climate change in the arctic. We simulate the release of methane from oceanic deposits, including the effects of fully-coupled heat transfer, fluid flow, hydrate dissociation, and other thermodynamic processes, for systems representative of segments of the Arctic Ocean margins. The modeling encompasses a range of shallow hydrate deposits from the landward limit of the hydrate stability zone down to water depths beyond the expected range of century-scale temperature changes. We impose temperature changes corresponding to predicted rates of climate change-related ocean warming and examine the possibility of hydrate dissociation and the release of methane. The assessment is performed at local-, regional-, and basin-scales. The simulation results are consistent with the hypothesis that dissociating shallow hydrates alone can result in significant methane fluxes at the seafloor. However, the methane release is likely to be confined to a narrow region of high dissociation susceptibility, defined by depth and temperature, and that any release will be continuous and controlled, rather than explosive. This modeling also establishes the first realistic bounds for methane release along the arctic continental shelf for potential hydrate dissociation scenarios, and ongoing work may help confirm whether climate ...
Date: July 1, 2011
Creator: Reagan, M.; Moridis, G.; Elliott, S.; Maltrud, M. & Cameron-Smith, P.
Partner: UNT Libraries Government Documents Department

Investigation of gas hydrate-bearing sandstone reservoirs at the "Mount Elbert" stratigraphic test well, Milne Point, Alaska

Description: In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S. Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole conditions, and therefore log data quality, were excellent due largely to the use of chilled oil-based drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT) wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This field program demonstrated the ability to safely and efficiently conduct a research-level openhole data acquisition program in shallow, sub-permafrost sediments. The program also demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and increased confidence in gas hydrate resource assessment methodologies for the ANS.
Date: January 1, 2008
Creator: Boswell, R.M.; Hunter, R. (ASRC Energy Services, Anchorage, AK); Collett, T. (USGS, Denver, CO); Digert, S. (BP Exploration (Alaska) Inc., Anchorage, AK); Hancock, S. (RPS Energy Canada, Calgary, Alberta, Canada); Weeks, M. (BP Exploration (Alaska) Inc., Anchorage, AK) et al.
Partner: UNT Libraries Government Documents Department

Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluationof Technology and Potential

Description: Gas hydrates are a vast energy resource with global distribution in the permafrost and in the oceans. Even if conservative estimates are considered and only a small fraction is recoverable, the sheer size of the resource is so large that it demands evaluation as a potential energy source. In this review paper, we discuss the distribution of natural gas hydrate accumulations, the status of the primary international R&D programs, and the remaining science and technological challenges facing commercialization of production. After a brief examination of gas hydrate accumulations that are well characterized and appear to be models for future development and gas production, we analyze the role of numerical simulation in the assessment of the hydrate production potential, identify the data needs for reliable predictions, evaluate the status of knowledge with regard to these needs, discuss knowledge gaps and their impact, and reach the conclusion that the numerical simulation capabilities are quite advanced and that the related gaps are either not significant or are being addressed. We review the current body of literature relevant to potential productivity from different types of gas hydrate deposits, and determine that there are consistent indications of a large production potential at high rates over long periods from a wide variety of hydrate deposits. Finally, we identify (a) features, conditions, geology and techniques that are desirable in potential production targets, (b) methods to maximize production, and (c) some of the conditions and characteristics that render certain gas hydrate deposits undesirable for production.
Date: February 12, 2008
Creator: Reagan, Matthew; Moridis, George J.; Collett, Timothy; Boswell, Ray; Kurihara, M.; Reagan, Matthew T. et al.
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) post-cruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.
Date: June 30, 2004
Creator: Rack, Frank & Party, ODP Leg 204 Shipboard Scientific
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.
Date: September 30, 2004
Creator: Rack, Frank R. & Party, ODP Leg 204 Shipboard Scientific
Partner: UNT Libraries Government Documents Department

Feasibility of monitoring gas hydrate production with time-lapse VSP

Description: In this work we begin to examine the feasibility of using time-lapse seismic methods-specifically the vertical seismic profiling (VSP) method-for monitoring changes in hydrate accumulations that are predicted to occur during production of natural gas.
Date: November 1, 2009
Creator: Kowalsky, M.B.; Nakagawa, S. & Moridis, G.J.
Partner: UNT Libraries Government Documents Department

A Domain Decomposition Approach for Large-Scale Simulations of Flow Processes in Hydrate-Bearing Geologic Media

Description: Simulation of the system behavior of hydrate-bearing geologic media involves solving fully coupled mass- and heat-balance equations. In this study, we develop a domain decomposition approach for large-scale gas hydrate simulations with coarse-granularity parallel computation. This approach partitions a simulation domain into small subdomains. The full model domain, consisting of discrete subdomains, is still simulated simultaneously by using multiple processes/processors. Each processor is dedicated to following tasks of the partitioned subdomain: updating thermophysical properties, assembling mass- and energy-balance equations, solving linear equation systems, and performing various other local computations. The linearized equation systems are solved in parallel with a parallel linear solver, using an efficient interprocess communication scheme. This new domain decomposition approach has been implemented into the TOUGH+HYDRATE code and has demonstrated excellent speedup and good scalability. In this paper, we will demonstrate applications for the new approach in simulating field-scale models for gas production from gas-hydrate deposits.
Date: July 1, 2008
Creator: Zhang, Keni; Moridis, G.J.; Wu, Y.-S. & Pruess, K.
Partner: UNT Libraries Government Documents Department

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

Description: Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope drilled and cored a well The HOT ICE No.1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report.
Date: July 1, 2004
Creator: Williams, Thomas E.; Millheim, Keith & King, Buddy
Partner: UNT Libraries Government Documents Department

Comparison of kinetic and equilibrium reaction models insimulating gas hydrate behavior in porous media

Description: In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas production from hydrates in various settings andfor the case of depressurization in a hydrate-bearing core duringextraction; and (2) examine the sensitivity to factors such as initialhydrate saturation, hydrate reaction surface area, and numericaldiscretization. We find that for large-scale systems undergoing thermalstimulation and depressurization, the calculated responses for bothreaction models are remarkably similar, though some differences areobserved at early times. However, for modeling short-term processes, suchas the rapid recovery of a hydrate-bearing core, kinetic limitations canbe important, and neglecting them may lead to significantunder-prediction of recoverable hydrate. The use of the equilibriumreaction model often appears to be justified and preferred for simulatingthe behavior of gas hydrates, given that the computational demands forthe kinetic reaction model far exceed those for the equilibrium reactionmodel.
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Partner: UNT Libraries Government Documents Department

Comparison of kinetic and equilibrium reaction models insimulating the behavior of porous media

Description: In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas production from hydrates in various settings andfor the case of depressurization in a hydrate-bearing core duringextraction; and (2) examine the sensitivity to factors such as initialhydrate saturation, hydrate reaction surface area, and numericaldiscretization. We find that for large-scale systems undergoing thermalstimulation and depressurization, the calculated responses for bothreaction models are remarkably similar, though some differences areobserved at early times. However, for modeling short-term processes, suchas the rapid recovery of a hydrate-bearing core, kinetic limitations canbe important, and neglecting them may lead to significantunder-prediction of recoverable hydrate. Assuming validity of the mostaccurate kinetic reaction model that is currently available, the use ofthe equilibrium reaction model often appears to be justified andpreferred for simulating the behavior of gas hydrates, given that thecomputational demands for the kinetic reaction model far exceed those forthe equilibrium reaction model.
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Partner: UNT Libraries Government Documents Department

Site Selection for DOE/JIP Gas Hydrate Drilling in the Northern Gulf of Mexico

Description: In the late spring of 2008, the Chevron-led Gulf of Mexico Gas Hydrate Joint Industry Project (JIP) expects to conduct an exploratory drilling and logging campaign to better understand gas hydrate-bearing sands in the deepwater Gulf of Mexico. The JIP Site Selection team selected three areas to test alternative geological models and geophysical interpretations supporting the existence of potential high gas hydrate saturations in reservoir-quality sands. The three sites are near existing drill holes which provide geological and geophysical constraints in Alaminos Canyon (AC) lease block 818, Green Canyon (GC) 955, and Walker Ridge (WR) 313. At the AC818 site, gas hydrate is interpreted to occur within the Oligocene Frio volcaniclastic sand at the crest of a fold that is shallow enough to be in the hydrate stability zone. Drilling at GC955 will sample a faulted, buried Pleistocene channel-levee system in an area characterized by seafloor fluid expulsion features, structural closure associated with uplifted salt, and abundant seismic evidence for upward migration of fluids and gas into the sand-rich parts of the sedimentary section. Drilling at WR313 targets ponded sheet sands and associated channel/levee deposits within a minibasin, making this a non-structural play. The potential for gas hydrate occurrence at WR313 is supported by shingled phase reversals consistent with the transition from gas-charged sand to overlying gas-hydrate saturated sand. Drilling locations have been selected at each site to 1) test geological methods and models used to infer the occurrence of gas hydrate in sand reservoirs in different settings in the northern Gulf of Mexico; 2) calibrate geophysical models used to detect gas hydrate sands, map reservoir thicknesses, and estimate the degree of gas hydrate saturation; and 3) delineate potential locations for subsequent JIP drilling and coring operations that will collect samples for comprehensive physical property, geochemical and other analyses.
Date: July 1, 2008
Creator: Hutchinson, D. R.; Shelander, D.; Dai, J.; McConnell, D.; Shedd, W.; Frye, M. et al.
Partner: UNT Libraries Government Documents Department

Laboratory measurements on core-scale sediment/hydrate samples topredice reservoir behavior

Description: Measurements on hydrate-bearing laboratory and field samplesare necessary in order to provide realistic bounds on parameters used innumerically modeling the production of natural gas from hydrate-bearingreservoirs. The needed parameters include thermal conductivity,permeability, relative permeability-saturation(s) relationships, andcapillary pressure-saturation(s) relationships. We have developed atechnique to make hydrate-bearing samples ranging in scale from coreplug-size to core-size in the laboratory to facilitate making thesemeasurements. In addition to pressure and temperature measurements, weuse x-ray computed tomography scanning to provide high-resolution dataproviding insights on processes occurring in our samples. Several methodsare available to make gas hydrates in the laboratory, and we expect thatthe method used to make the hydrate will impact the behavior of thehydrate sample, and the parameters measured.
Date: November 2, 2005
Creator: Kneafsey, Timothy J.; Seol, Yongkoo; Moridis, George J.; Tomutsa,Liviu & Freifeld, Barry M.
Partner: UNT Libraries Government Documents Department

International Collaboration on CO2 Sequestration

Description: This reporting period covers the first half of the two-year sub-task, which includes a review of recent and ongoing engineering studies concerning practical modes for the ocean discharge of CO{sub 2}, review of recent and ongoing experimental studies concerning the rates (and extent) of formation and dissolution for CO{sub 2} hydrates, review of recent and ongoing biological studies concerning organism response to reduced pH and increased CO{sub 2} concentration, and the definition of discharge scenarios. These steps have been successfully completed. Results-to-date were presented at the Annual Fall Meeting of AGU (December 2005) and will be presented at the Annual DOE Meeting on Carbon Capture and Sequestration (May, 2006). The objective during this reporting period was to begin a two-year sub-task to update an assessment of environmental impacts from direct ocean sequestration. The approach is based on the work of Auerbach et al. (1997) and Caulfield et al. (1997) to assess acute impacts, but uses updated information concerning injection scenarios and bioassays.
Date: May 19, 2006
Creator: Herzog, Howard J. & Adams, E. Eric
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occuring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Leg 204 scientific party members presented preliminary results and operational outcomes of ODP Leg 204 at the American Geophysical Union Fall meeting, which was held in San Francisco, CA; and, (2) a report was prepared by Dr. Gilles Guerin and David Goldberg from Lamont-Doherty Earth Observatory of Columbia University on their postcruise evaluation of the data, tools and measurement systems that were used for vertical seismic profiling (VSP) experiments during ODP Leg 204. The VSP report is provided herein. Intermediate in scale and resolution between the borehole data and the 3-D seismic surveys, the Vertical Seismic Profiles (VSP) carried during Leg 204 were aimed at defining the gas hydrate distribution on hydrate ridge, and refining the signature of gas hydrate in the seismic data. VSP surveys were attempted at five sites, following completion of the conventional logging operations. Bad hole conditions and operational difficulties did not allow to record any data in hole 1245E, but vertical and constant offset VSP were successful in holes 1244E, 1247B and 1250F, and walk-away VSP were successfully completed in holes 1244E, 1250F and 1251H. Three different tools were used for these surveys. The vertical VSP provided the opportunity to calculate interval velocity that could be compared and validated with the sonic logs in the same wells. The interval velocity profiles in Holes 1244E and 1247B are in very good agreement with the sonic logs. Information about the Leg 204 presentations at the AGU meeting are included in a separate Topical Report, which has been provided to DOE/NETL in addition to this Quarterly Report. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans ...
Date: December 31, 2003
Creator: Rack, Frank; Guerin, Gilles; Goldberg, David & Party, ODP Leg 204 Shipboard Scientific
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Frank Rack, Anne Trehu, and Tim Collett presented preliminary results and operational outcomes of ODP Leg 204 at the American Association of Petroleum Geologists annual meeting in Salt Lake City, UT; (2) several Leg 204 scientists participated in special hydrate sessions at the international EGS/AGU/EUG meeting in Nice, France and presented initial science results from the cruise, which included outcomes arising from this cooperative agreement; and, (3) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. At the EGS/EUG/AGU meeting in Nice, France in April, Leg 204 Co-chiefs Anne Trehu and Gerhard Bohrmann, as well as ODP scientists Charlie Paull, Erwin Suess, and Jim Kennett, participated in a press conference on hydrates. The well-attended press conference entitled ''Gas Hydrates: Free methane found and controversy over the 'hydrate gun''' led to stories in Nature on-line and BBC radio, among others. There were six (6) oral and fifteen (15) poster presentations on ODP Leg 204 hydrate science at the EGS/AGU/EUG Meeting in Nice, France on April 6-11, 2003. This was a very strong showing at a meeting just over six month following the completion of the drilling cruise and highlighted many of the results of the leg, including the results obtained with instruments and equipment funded under this cooperative agreement. At the AAPG annual meeting in Salt Lake City, UT on May 11-14, 2003, Anne Trehu gave an oral presentation about the scientific results of Leg 204, and Frank Rack presented a poster outlining the operational and technical accomplishments. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as ...
Date: June 30, 2003
Creator: Rack, Frank & Party, ODP Leg 204 Shipboard Scientific
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments during the first quarter were to mobilize materials and supplies to meet the deployment schedule for equipment and activities, as proposed under the DOE/NETL cooperative agreement with JOI, with initial testing and use of specialized tools and equipment on Ocean Drilling Program (ODP) Leg 201. As a requirement of the award, two copies of a technical feasibility report entitled ''Preliminary Evaluation of Existing Pressure/Temperature Coring Systems'' were delivered to DOE/NETL on October 22, 2001. The report was written to provide a discussion of the availability and compatibility of the four existing pressure coring devices in existence. Most of these systems are available for use by JOI/ODP aboard the D/V JOIDES Resolution, via purchase, lease, modification, etc. and the proposed capabilities to upgrade existing devices or systems for use on other platforms. In addition, the report provided a discussion of the compatibility of each existing coring device in conjunction with the use of the other coring devices, such as the advanced piston coring (APC) system used by ODP. Based on an evaluation of the JOI report, the DOE/NETL Program Manager William Gwilliam provided a ''Go'' decision to JOI for the further development of the ODP Pressure Coring System (PCS) and PCS Gas Manifold. During the reporting period negotiations were conducted with various potential subcontractors and vendors to establish the specific cost-sharing arrangements and work breakdown necessary to definitize the terms of the DOE/NETL cooperative agreement with JOI. The discussions were communicated with the DOE/NETL Program Manager, William Gwilliam, to keep NETL closely informed about events as this project evolved. A series of meetings were also held with ODP engineers, technical staff, and to plan for the implementation of the various tasks outlined in the JOI proposal to DOE for deployment during ODP Legs 201 and 204. These meetings ...
Date: December 31, 2001
Creator: Rack, Frank
Partner: UNT Libraries Government Documents Department

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

Description: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were (1) the preliminary postcruise evaluation of the tools and measurement systems that were used during ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September 2002; and (2) the preliminary study of the hydrate-bearing core samples preserved in pressure vessels and in liquid nitrogen cryofreezers, which are now stored at the ODP Gulf Coast Repository in College Station, TX. During ODP Leg 204, several newly modified downhole tools were deployed to better characterize the subsurface lithologies and environments hosting microbial populations and gas hydrates. A preliminary review of the use of these tools is provided herein. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were used extensively and successfully during ODP Leg 204 aboard the D/V JOIDES Resolution. These systems provided a strong operational capability for characterizing the in situ properties of methane hydrates in subsurface environments on Hydrate Ridge during ODP Leg 204. Pressure was also measured during a trial run of the Fugro piezoprobe, which operates on similar principles as the DVTP-P. The final report describing the deployments of the Fugro Piezoprobe is provided in Appendix A of this report. A preliminary analysis and comparison between the piezoprobe and DVTP-P tools is provided in Appendix B of this report. Finally, a series of additional holes were cored at the crest of Hydrate Ridge (Site 1249) specifically geared toward the rapid recovery and preservation of hydrate samples as part of a hydrate geriatric study partially funded by the Department of Energy (DOE). In addition, the preliminary results from gamma density non-invasive imaging of the cores preserved in pressure vessels are provided in Appendix C of this report. An initial visual inspection of the samples stored in liquid ...
Date: December 31, 2002
Creator: Rack, Frank; Storms, Michael; Schroeder, Derryl; Dugan, Brandon; Schultheiss, Peter & Party, ODP Leg 204 Shipboard Scientific
Partner: UNT Libraries Government Documents Department

SUPPORT OF GULF OF MEXICO HYDRATE RESEARCH CONSORTIUM: ACTIVITIES TO SUPPORT ESTABLISHMENT OF A SEA FLOOR MONITORING STATION PROJECT

Description: The Gulf of Mexico Hydrates Research Consortium was established in 1999 to assemble leaders in gas hydrates research. The group is administered by the Center for Marine Resources and Environmental Technology, CMRET, at the University of Mississippi. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory on the sea floor in the northern Gulf of Mexico by the year 2005, in an area where gas hydrates are known to be present at, or just below, the sea floor. This mission necessitates assembling a station that will monitor physical and chemical parameters of the sea water and sea floor sediments on a more-or-less continuous basis over an extended period of time. Development of the station has always included the possibility of expanding its capabilities to include biological monitoring, as a means of assessing environmental health. This possibility has recently received increased attention and the group of researchers working on the station has expanded to include several microbial biologists. Establishment of the Consortium has succeeded in fulfilling the critical need to coordinate activities, avoid redundancies and communicate effectively among researchers in this relatively new research arena. Complementary expertise, both scientific and technical, has been assembled to promote innovative research methods and construct necessary instrumentation. Initial components of the observatory, a probe that collects pore-fluid samples and another that records sea floor temperatures, were deployed in Mississippi Canyon 118 in May of 2005. Follow-up deployments are planned for fall 2005 and center about the use of the vessel M/V Ocean Quest and its two manned submersibles. The subs will be used to effect bottom surveys, emplace sensors and sea floor experiments and make connections between sensor data loggers and the integrated data power unit (IDP). Station/observatory completion is anticipated for 2007 following the ...
Date: March 1, 2006
Creator: Higley, Paul; Woolsey, J. Robert; Goodman, Ralph; Asper, Vernon; Mizaikoff, Boris; Davis, Angela et al.
Partner: UNT Libraries Government Documents Department

The Use of Horizontal Wells in Gas Production from Hydrate Accumulations

Description: The amounts of hydrocarbon gases trapped in natural hydrate accumulations are enormous, leading to a recent interest in the evaluation of their potential as an energy source. Earlier studies have demonstrated that large volumes of gas can be readily produced at high rates for long times from gas hydrate accumulations by means of depressurization-induced dissociation, using conventional technology and vertical wells. The results of this numerical study indicate that the use of horizontal wells does not confer any practical advantages to gas production from Class 1 deposits. This is because of the large disparity in permeabilities between the hydrate layer (HL) and the underlying free gas zone, leading to a hydrate dissociation that proceeds in a horizontally dominant direction and is uniform along the length of the reservoir. When horizontal wells are placed near the base of the HL in Class 2 deposits, the delay in the evolution of a significant gas production rate outweighs their advantages, which include higher rates and the prevention of flow obstruction problems that often hamper the performance of vertical wells. Conversely, placement of a horizontal well near to top of the HL can lead to dramatic increases in gas production from Class 2 and Class 3 deposits over the corresponding production from vertical wells.
Date: April 15, 2008
Creator: Reagan, Matthew; Moridis, George J.; Reagan, Matthew T. & Zhang, Keni
Partner: UNT Libraries Government Documents Department

Support of Gulf of Mexico Hydrate Research Consortium: Activities of Support Establishment of a Sea Floor Monitoring Station Project

Description: The Gulf of Mexico Hydrates Research Consortium (GOM-HRC) was established in 1999 to assemble leaders in gas hydrates research that shared the need for a way to conduct investigations of gas hydrates and their stability zone in the Gulf of Mexico in situ on a more-or-less continuous basis. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory (SFO) on the sea floor in the northern Gulf of Mexico, in an area where gas hydrates are known to be present at, or just below, the sea floor and to discover the configuration and composition of the subsurface pathways or 'plumbing' through which fluids migrate into and out of the hydrate stability zone (HSZ) to the sediment-water interface. Monitoring changes in this zone and linking them to coincident and perhaps consequent events at the seafloor and within the water column is the eventual goal of the Consortium. This mission includes investigations of the physical, chemical and biological components of the gas hydrate stability zone - the sea-floor/sediment-water interface, the near-sea-floor water column, and the shallow subsurface sediments. The eventual goal is to monitor changes in the hydrate stability zone over time. Establishment of the Consortium succeeded in fulfilling the critical need to coordinate activities, avoid redundancies and communicate effectively among those involved in gas hydrates research. Complementary expertise, both scientific and technical, has been assembled to promote innovative methods and construct necessary instrumentation. Following extensive investigation into candidate sites, Mississippi Canyon 118 (MC118) was chosen by consensus of the Consortium at their fall, 2004, meeting as the site most likely to satisfy all criteria established by the group. Much of the preliminary work preceding the establishment of the site - sensor development and testing, geophysical surveys, and laboratory studies - has been ...
Date: May 31, 2008
Creator: Woolsey, J. Robert; McGee, Thomas & Lutken, Carol
Partner: UNT Libraries Government Documents Department

Support of Gulf of Mexico Hydrate Research Consortium: Activities to Support Establishment of a Sea Floor Monitoring Station Project

Description: The Gulf of Mexico Hydrates Research Consortium (GOM-HRC) was established in 1999 to assemble leaders in gas hydrates research. The Consortium is administered by the Center for Marine Resources and Environmental Technology, CMRET, at the University of Mississippi. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory (MS/SFO) on the sea floor in the northern Gulf of Mexico by the year 2007, in an area where gas hydrates are known to be present at, or just below, the sea floor. This mission, although unavoidably delayed by hurricanes and other disturbances, necessitates assembling a station that will monitor physical and chemical parameters of the marine environment, including sea water and sea-floor sediments, on a more-or-less continuous basis over an extended period of time. In 2005, biological monitoring, as a means of assessing environmental health, was added to the mission of the MS/SFO. Establishment of the Consortium has succeeded in fulfilling the critical need to coordinate activities, avoid redundancies and communicate effectively among researchers in the arena of gas hydrates research. Complementary expertise, both scientific and technical, has been assembled to promote innovative research methods and construct necessary instrumentation. The observatory has now achieved a microbial dimension in addition to the geophysical, geological, and geochemical components it had already included. Initial components of the observatory, a probe that collects pore-fluid samples and another that records sea floor temperatures, were deployed in Mississippi Canyon 118 (MC118) in May of 2005. Follow-up deployments, planned for fall 2005, had to be postponed due to the catastrophic effects of Hurricane Katrina (and later, Rita) on the Gulf Coast. Station/observatory completion, anticipated for 2007, will likely be delayed by at least one year. These delays caused scheduling and deployments difficulties but many sensors and instruments were completed ...
Date: March 31, 2007
Creator: Woolsey, J. Robert; McGee, Thomas M.; Lutken, Carol Blanton & Stidham, Elizabeth
Partner: UNT Libraries Government Documents Department