Analysis of gashydrate provinces by oceanbottom seismic methods. This technology assessment for gas hydrates research and development is. Hence, the detection, characterization and quantification of gas hydrates are very important for evaluating the resource potential. Geophysical characterization of gas hydrate systems of the. Current research and development at gas technology institute is focused on characterization of natural gas hydrates as an energy resource. They form and remain stable under low temperatures often. Pdf clathrate gasmethane hydratewhite gold crystal fuel is a. Gas hydrates and shallow marine research have been andrews major research efforts since his move to new zealand in 2003. Request pdf geophysical characterization of a finegrained gas hydrate reservoir in the shenhu area, northern south china sea. The study and research on hydrate became of interest to the oil and gas industry in 1934 when the first pipeline blockage was observed by hamrnerschmidt. The extensive continental shelves of new zealand which cover an area several times as large as the exposed island nation straddle the pacific australian plate boundary. Resource characterization and quantification of natural gas. Since the last interpretation special section on gas hydrates in february 2016, many advances have been made in the characterization and understanding of gas hydrate systems.
Geophysical methods to quantify gas hydrates and free gas in the shallow subsurface. Geophysical methods to quantify gas hydrates and free gas. Electromagnetic methods are directly sensitive to electrically resistive gas hydrates and can be used to characterize and quantify hydrate deposits. These are solid, crystalline, icelike substances found in permafrost areas and deepwater basins around the world. Characterization and identification of gas hydrate bearing. Seismic characterization of a gas hydrate system in the.
Gas hydrate is an icelike compound formed from gas, mostly methane, trapped within a lattice of water molecules sloan, 1998. This seg publication, geophysical characterization of gas hydrates geophysical developments no. Pdf seismic analysis and characterization of gas hydrates. The depth extent and stability of the hydrate zone are governed by the phase diagram for mixtures of methane and hydrate, determined by ambient pressures and temperatures. High concentrated gas hydrate deposits in finegrained sediment are proved to be eligible for exploitation with the current technology. Geophysical characterization of a finegrained gas hydrate. We use this difference to identify the gas hydrate occurrences state and apply it in northern south china sea. Research performance progress report period ending 0930. Seismic characterization of a gas hydrate system in the gulf of mexico using wideaperture data.
Integrated threedimensional seismic, logging, sediment cores, and geochemical testing data were collected from guangzhou marine geological survey 3 and 4 hydrate drilling expeditions and used in this study for a comprehensive investigation of the geological and geophysical features and accumulation mechanism of hydrates in the first offshore gashydrate production test region ghptr in the. The analysis of geophysical dataset acquired during three geophysical cruises allowed us to characterize this reservoir. Gas hydrates contain more than half of the organic carbon of the earth 1. Gas hydrates geophysical exploration techniques and methods michael riedel, eleanor c. Therefore, they become an enormous resource of natural gas and are considered as a main energy resource for future. The morphology of gas hydrates has large effects on sedimentary physical properties, from seismic velocities on a large scale to borehole electrical resistivity on a smaller scale, and, therefore, the gas hydrate morphology impacts the amount of gas hydrate saturation estimated from geophysical data. Applicants are encouraged to use the following documents for additional guidance in performing site characterization activities see section viii. Estimating the amount of gas hydrate and free gas from marine. Analysis of seismic data from green canyon area reveal that gas hydrates are usually confined to permeable sand layers causing large changes in velocity across. The gas hydrates are mostly identified by mapping bottom simulating reflectors on seismic section, and gas hydrate stability zone thickness of the area. Detection methods, morphology, and relevant physical properties of gas hydratebearing sediments are also discussed. Gas hydrates have high capacity to store methane gas1 cubic metre of a typical hydrate contains approximately 180 standard cubic metres of methane gas at standard temperature and pressure 1. Pdf geophysical prospecting of gas hydrate researchgate. Geochemical characterization of concentrated gas hydrate.
Geophysical characterization of gas hydrates seg library. Seismic characterization of a gas hydrate system in the gulf. Identifying gas hydrate occurrence state by seismic pwave. Marine gas hydrates, ii geophysical evidence, in natural gas hydrates. Nevertheless, new insights and more understandings of the accumulation of gas hydrate and characterization of hydrate reservoir in finegrained sediment are required, which can facilitate the commercial production of gas hydrate in the future. Pdf seismic data processing and the characterization of a. They occur worldwide in sediment beneath the seafloor and estimates of the total mass available there exceed 10 16 kg. On the resource evaluation of marine gashydrate deposits. Gas hydrates, or clathrate hydrates, are crystalline solids resembling ice, in which small guest molecules, typically gases, are trapped inside cavities formed by hydrogenbonded water host molecules. Energies free fulltext offshore antarctic peninsula gas. Estimating the amount of gas hydrate and free gas from marine seismic data christine ecker formerly stanford university, department of geophysics, stanford, california 943052215. The hikurangi margin, east of new zealands north island, is a large marine gas hydrate. This book is the first of two edited volumes, with chapters on the experimental and modeling tools used for characterizing and predicting the unique molecular, thermodynamic and kinetic properties of gas hydrates volume 1 and on gas hydrates in their natural environment and for potential industrial applications volume 2.
Geophysical characterizations of fluid flow and gas. Gas hydrates were discovered in a mud mound in the lease block mississippi canyon 798, gulf of mexico, through piston coring. Although other gases form hydrate, such as co 2 and h 2 s, methane is the most common gas, estimated to make up more than 99 per cent of naturally occurring hydrates paull 1994. Jun 30, 2017 this book is the first of two edited volumes, with chapters on the experimental and modeling tools used for characterizing and predicting the unique molecular, thermodynamic and kinetic properties of gas hydrates volume 1 and on gas hydrates in their natural environment and for potential industrial applications volume 2. Seismic data processing and the characterization of a gas hydrate bearing zone offshore of southwestern taiwan. Characterization and quantification of gas hydrates in the. Natural gas which is mainly methane is used as fuel because the technologies for handling it directly. Constraints from highresolution geophysical survey by auv, proceedings of the 7th international conference on gas hydrates icgh 2011, edinburgh, scotland, united kingdom, july 1721, 2011. The most recent estimates of gas hydrate abundance suggest that they contain. Gas hydrate is a naturally occurring, icelike substance that forms when water and gas combine under high pressure.
These occurrences have unique and differing relevance to issues of future energy supply, longterm global carbon. Updated and more practical than ever, natural gas hydrates, third edition helps managers and engineers get up to speed on all the most common hydrate types, how to forecast when they will appear, and safely mitigate their removal. We found that the total volume of natural gas held in these hydrates is roughly a trillion cubic meters, enough to fill dallas cowboys stadium with natural gas over three hundred thousand times. Hydrates are stable only within a narrow range of pressure and temperature, which exists in some marine and arctic areas within a limited depth range that is known as the gas hydrate stability zone ghsz. Gas hydrate is a type of clathrate consisting of a gas molecule usually methane encased in a water lattice, and is found worldwide in marine and permafrost regions. Characterization of natural gas hydrates research current research and development at gas technology institute is focused on characterization of natural gas hydrates as an energy resource. We combine an integrated study of gas hydrate reservoirs in a marine area from seismic data which collected for oil and gas exploration purpose. Gas hydrate deposits are found wherever methane occurs in the presence of water under elevated pressure and at relatively low temperature, such as. Abstract gas hydrates were discovered in a mud mound in the lease block mississippi canyon 798, gulf of mexico, through piston coring. Geophysical characterization of potential longcore sites for northern gulf of mexico gas hydrate studies investigations of naturally occurring gas hydrates on the upper to middle continental slope of the northern gulf of mexico have included high resolution seismicreflection surveys and shallow subbottom sampling with seafloor cores. Seismic data analysis indicated high gas hydrate concentration and extremely.
The analysis of seismic data reveals that gas hydrates in this region have formed by the upward migration of dissolved gas through fracture. The global climate change is a particularly sensitive issue for the polar regions, such as antarctica. Seismic characterization of gas hydrates and associated fluid. United states department of the interior bureau of.
This was due to the crystalline, nonflowing nature of hydrates. Gas hydrate characterization in the gulf of mexico dent0005668 and mapping permafrost. In geophysical view bsr and other gas hydrate related attributes are clearly observed on the seismic sections of oman 9. Gas hydrates 1 fundamentals, characterization and modeling. Porescale effect on the hydrate variation and flow. Heterogeneous distribution of gas hydrate and free gas in glaciated sediments of the nwsvalbard continental margin inferred from changes in compressional wave velocity to be submitted. Geophysical characterization of gas hydrates book, 2010. The gas hydrates gradually accumulates in the pore phase with the growth of the hydrate, as shown in figs. Gas hydrate in nature gas hydrate is a naturally occurring, icelike substance that forms when water and gas combine. Geophysical characterization of a finegrained gas hydrate reservoir in the shenhu area, northern south china sea. These resistivity models tell us where, and how much, hydrate is located in our study area the santa cruz basin, located offshore southern california. Scientific results from the jogmecnrcanaurora mallik 20072008 gas hydrate production research well program. Gas hydrates are frozen, waterbased crystalline solids that trap methane inside. Gas hydrates consist of molecules of natural gas most commonly methane enclosed within a solid lattice of water molecules.
A fundamental but realistic assumption of this approach is that high acoustic impedances indicate gas hydrates in. Seismic analysis and characterization of gas hydrates in. Geological and geophysical features of and controls on. Gas hydrate was discovered by sir humphrey day in 1810. United states department of the interior bureau of ocean. Seismic attenuation for characterization of gas hydrate. Integration of seismic data and downhole logs high concentrated. Here the study area is oman sea, bsr is chosen as a gas hydrate indicator and seismic sections with strong and obvious bsr are selected for various analysis figure 1. Offshore antarctic peninsula gas hydrate reservoir characterization by geophysical data analysis maria filomena loreto, umberta tinivella, flavio accaino and michela giustiniani national institute of oceanography and experimental geophysicsogsborgo grotta gigante. Estimating the amount of gas hydrate and free gas from. Recent geochemical and geophysical investigation of hydrates on the cascadia margin, midchilean coast, and texaslouisiana shelf demonstrated a need to combine these data for prediction of deep sediment hydrate deposits. Seismic characterization of gas hydrate accumulations in a. Offshore antarctic peninsula gas hydrate reservoir. In the south shetland margin antarctic peninsula, the occurrence of a.
His work has been facilitated by substantial academic marine research facilities within the country, which includes the university of otagos own research vessel, polaris ii, equipped for coastal marine geophysical surveys. Integrated geologicgeophysical characterization methodologies to enable. Seismic studies for gas hydrate characterization in a. Hydrate is important because it is a geohazard, has potential as an energy resource, and is a possible contributor to climate change. Methane hydrates are also recognized as, an influence on offshore platform stability, a major factor in climate change contributing to global warming and a significant contribution to the ocean carbon cycle. Because of the thermodynamic characteristics of gas hydrate, there is no. Detection of gas hydrates though seismic and other remote sensing methods has been demonstrated through drilling and coring programs. By using the two different analytical methods xray powder diffraction xrd and gas chromatography. The data were processed with a bin spacing in the inline and crossline. Technology assessments executive summary recent research confirms that gas hydrates are abundant in nature and exist in a wide variety of forms. Seismic studies for gas hydrate characterization in a marine.
Seismic attribute analysis for gashydrate and freegas prospects on the. Methane hydrates are solid, nonstochiometric mixtures of water and the gas methane. The usgs geologic and geophysical studies of the eileen gas hydrate trend on the. Gas hydrate prospecting and characterization onepetro. Methane is the most common gas present in gas hydrate, although other gases may also be included in hydrate structures, particularly in areas. Correlation of geophysical attributes to gas hydrate occurrence are also under investigation. Gas hydrates are abundant at the two active continental margins, as indicated by the stippled pattern. Obviously, hydrates increase with increasing depth. Seismic data processing and the characterization of a gas hydrate bearing zone offshore of southwestern taiwan hui deng1, 2, 4, 5, pin yan1, 3, hailing liu1, and wenzao luo1 manuscript received 4 september 2005, in final form 15 may 2006 abstract 1 cas key laboratory of marginal sea geology, south china sea institute of oceanology, chinese. Gas hydratesassociated bsrs have been recognized from the seismic data of other geophysical studies, and their presences have been validated by drilling or coring either in accretionary wedges 47 or in the continental margin of the world 811. The fundamental research objective is to develop a fundamental understanding of hydrate bearing sediments as reservoir rocks. Since each volume of hydrate can yield up to 164 volumes of gas, offshore methane hydrate is recognized as a very important natural energy resource.
Department of energy doe and its research partners in understanding, predicting, and testing the recoverability and potential production characteristics of onshore natural gas hydrate in the greater prudhoe bay area on the alaska north slope ans prudhoe bay, kuparuk river, and milne point areas or other areas deemed suitable. In our study we have been focusing on characterization of gas hydrate structures and their gas composition. Willoughby, and satinder chopra motivations for the geophysical investigation of gas hydrates ray boswell and tatsuo saeki introduction to seismic imaging michael riedel, eleanor c. Seismic characterization of gas hydrates and associated. Gas hydrates had been considered selfsealing but evidence from pressure cores and laboratory experiments indicate that gas hydrate deposits may need local seals. Geophysical characterization of potential longcore. Abstract geophysical baseline characterization of subsurface. First, geological analysis is made using data of material sources, structures and sediments to determine the hydrocarbon formation conditions of gas hydrate. Seismic attributes for characterization of gas hydrate and.
Gas hydrates have received global attention as a possible alternative nonconventional energy resource. Gas hydrates are still relatively poorly understood with many questions to be answered. The fundamental research objective is to develop a fundamental understanding of hydratebearing sediments as reservoir rocks. Rarely covered in formal engineering courses, natural gas hydrates are a common problem and reallife danger for engineers worldwide. The results depict that the pwave attenuation is an effective attribute to identify gas hydrate occurrence states, which lays a foundation for the identification of gas hydrate occurrence state by seismic pwave attenuation. Seismic characterization of a gas hydrate system in the gulf of mexico using wide. The proposed book treats various geophysical techniques in order to quantify the gas hydrate reserves and their impact on environment. Pecher, seismic characterization of a gas hydrate system in the gulf of mexico using wideaperture data, geophysical journal international, volume 165, issue 1, april 2006. The natural gas hydrates do have the potential of becoming an alternate energy resources due to their huge deposits envisaged worldwide. Although these deposits look like ice, they turn to water and gas when pressure is. Gas hydrates are naturally occurring solids comprised of water molecules that form a rigid lattice of cages around gas molecules of low molecular weight. Gas hydrates are icelike crystalline substances that form a rigid cage of water molecules and entrap hydrocarbon and nonhydrocarbon gas by hydrogen bonding. A gas hydrate reservoir, identified by the presence of the bottom simulating reflector, is located offshore of the antarctic peninsula.
This interagency agreement is intended to support the u. Seismic data processing and the characterization of a gas. Read local seismic quantification of gas hydrates and bsr characterization from multifrequency obs data at northern hydrate ridge, earth and planetary science letters on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at. This study combines analyses of geology and seismology. Willoughby, and satinder chopra seismic indicators of natural.
Exploration of gas hydrates geophysical techniques. Since each volume of hydrate can yield up to 164 volumes of gas, offshore methane hydrate is recognized as a very important natural energy. Maria filomena loreto, umberta tinivella, flavio accaino and michela giustiniani. Pdf offshore antarctic peninsula gas hydrate reservoir. Natural gas hydrate is primarily composed of water and methane. There is a lot of hydrate on earth, but our understanding of where it is, and how much there is, is still evolving. The ongoing gas hydrate production test design part of this ia has been established to provide the. The true amplitude, noise attenuation, and deconvolution were used to emphasize the characterization of gas hydrate. As the bsr might be due to other reasons, therefore for confirming the presence of gas hydrates in a region, it is pertinent to examine the non geophysical proxies geochemical and. Subsequently, a seismic experiment was carried out to investigate the dynamics behind the hydrate formation. They form and remain stable under low temperatures often well below ambient conditions and high pressures ranging from a few bar to hundreds of bar, depending on the guest molecule. During the last few decades, interest in gas hydrates has been increasing significantly because of their economic potential as future energy source and their potential role in geohazards and global climate change. With improving data collection techniques and analytic methods, both in the field and in the lab, our knowledge of the gas hydrates system has drastically improved in the last several years.
1298 1506 790 779 1022 235 1206 226 615 990 1196 550 975 1154 660 329 65 359 1497 1107 817 340 361 434 158 375 489 448 339 255 697 14 1289