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Timothy S Collett - One of the best experts on this subject based on the ideXlab platform.
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Permafrost-Associated Gas Hydrate
Coastal Systems and Continental Margins, 2020Co-Authors: Timothy S Collett, Scott R. DallimoreAbstract:Gas Hydrate in onshore arctic environments is typically closely associated with permafrost. It is generally believed that thermal conditions conducive to the formation of permafrost and Gas Hydrate have persisted in the Arctic since the end of the Pliocene (about 1.88 Ma). Maps of present day permafrost reveal that about 20 percent of the land area of the northern hemisphere is underlain by permafrost (Fig. 1). Geologic studies (MacKay, 1972; Lewellen, 1973; Molochushkin, 1978) and thermal modeling of subsea conditions (Osterkamp and Fej, 1993) also indicate that permafrost and Gas Hydrate may exist within the continental shelf of the Arctic Ocean. Subaerial emergence of portions of the Arctic continental shelf to current water depths of 120 m (Bard and Fairbanks, 1990) during repeated Pleistocene glaciations, subjected the exposed shelf to temperature conditions favorable to the formation of permafrost and Gas Hydrate. Thus, it is speculated that “relic” permafrost and Gas Hydrate may exist on the continental shelf of the Arctic Ocean to present water depths of 120 m. In practical terms, onshore and nearshore Gas Hydrate can only exist in close association with permafrost, therefore, the map in Figure 1 that depicts the distribution of onshore continuous permafrost and the potential extent of “relic” sub-sea permafrost also depicts the potential limit of onshore and nearshore Gas Hydrate.
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Natural Gas Hydrate as a Potential Energy Resource
Coastal Systems and Continental Margins, 2020Co-Authors: Timothy S CollettAbstract:The estimated amount of Gas in the Hydrate accumulations of the world greatly exceeds the volume of known conventional Gas reserves. However, the role that Gas Hydrate will play in contributing to the world’s energy requirements will depend ultimately on the availability of sufficient Gas Hydrate resources and the “cost” to extract them. Yet considerable uncertainty and disagreement prevails concerning the world’s Gas Hydrate resources. Disagreements over fundamental issues such as volume of Gas stored within delineated Gas Hydrate accumulations and the concentration of Gas Hydrate within Hydrate-bearing reservoirs have demonstrated that we know very little about Gas Hydrate.
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india national Gas Hydrate program expedition 02 summary of scientific results Gas Hydrate systems along the eastern continental margin of india
Marine and Petroleum Geology, 2019Co-Authors: Timothy S Collett, Ray Boswell, Pushpendra Kumar, William F Waite, Krishan Chopra, Sunil Kumar Singh, Yasuhiro Yamada, Norio Tenma, John W Pohlman, Margarita V ZyrianovaAbstract:Abstract The primary objectives of the India National Gas Hydrate Program Expedition 02 (NGHP-02) were to obtain new data on the occurrence of Gas Hydrate systems and to advance the understanding of the controls on the formation of Gas Hydrate accumulations in the offshore of India. In accordance with the ultimate overall goal of the NGHP effort to assess the energy resource potential of marine Gas Hydrates in India, particular focus was placed on the exploration and evaluation of Gas Hydrate occurrences at high saturations in sand-rich systems. NGHP-02 operations were conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India and included logging while drilling (LWD) operations at 25 locations, and coring and wireline logging operations at 10 locations, in the Krishna-Godavari and Mahanadi Basins. The formation of highly concentrated Gas Hydrate accumulations, which are more suitable for energy extraction, requires the presence of relatively coarse-grained sediments with porosity needed to support the migration and accumulation of Gas, and the nucleation of Gas Hydrate. The results of downhole logging, coring and formation pressure testing operations during NGHP-02 have confirmed the presence of extensive sand-rich depositional systems throughout the deepwater portions of the Krishna-Godavari and Mahanadi Basins. Two areas of the Krishna-Godavari Basin, referred to as Areas B and C, contain substantial Gas Hydrate accumulations in sand-rich systems and therefore represent ideal candidate sites for future Gas Hydrate production testing. This summary and technical report includes a comprehensive synthesis of the geologic, geophysical, geochemical, and physical property data acquired during NGHP-02 as it relates to the controls on Gas Hydrate occurrence, particularly with regards to sand-hosted accumulations. In the Mahanadi Basin, despite the confirmation of extensive reservoir capacity, Gas supply at the NGHP-02 sites was insufficient to charge the reservoirs with Gas Hydrates. In the Krishna-Godavari Basin, extensive reservoir systems were confirmed with sediment grain-sizes ranging from coarse-silts to gravels. These reservoirs range from fully- to partially-filled with Gas Hydrate. The Gas is determined to be from only microbial sources, and in part migrated into the reservoirs from deeper systems. The controls on Gas Hydrate occurrence are complex and varied; and include substantial reservoir heterogeneity and sufficient permeability throughout the reservoirs and seals that allowed pervasive fluid flow into and through the Hydrate-bearing systems. These discoveries are the most significant confirmation of the exploration approach that focuses on direct detection of Hydrate reservoirs supported by comprehensive petroleum systems analyses.
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india national Gas Hydrate program expedition 02 operational and technical summary
Marine and Petroleum Geology, 2019Co-Authors: Pushpendra Kumar, Timothy S Collett, K M Shukla, U S Yadav, M V Lall, Krishna VishwanathAbstract:Abstract The India National Gas Hydrate Program is being steered by the government of India's Ministry of Petroleum and Natural Gas (MoPNG) with participation of Directorate General of Hydrocarbons (DGH), Oil and Natural Gas Corporation Limited (ONGC), and the National Oil Companies and Research Institutes of India. The India National Gas Hydrate Program Expedition 01 (NGHP-01) established the presence of Gas Hydrate in the Krishna Godavari (KG) and Mahanadi Basins and in the offshore area of the Andaman Sea Basin. However, the Gas Hydrates discovered during NGHP-01 were mainly distributed as fracture-filling material in fine-grained clay-rich sediments. The India National Gas Hydrate Program Expedition 02 (NGHP-02) was carried out with an objective to discover Gas Hydrate in sand-rich sediment along the eastern offshore margin of India. ONGC planned and executed NGHP-02 on the behalf of the MoPNG. NGHP-02 started on March 3, 2015 and was completed on July 28, 2015 (total 147 days) using the Japanese scientific Drilling Vessel Chikyu (D/V Chikyu). During NGHP-02, 42 holes at 25 sites were drilled, cored, and/or surveyed with downhole logging tools. These sites were located in four areas along the eastern margin of India and formally named Area A (Mahanadi Basin, three sites), Area B (northern part of the KG-Basin, twelve sites), Area C (central part of the KG-Basin, six sites), and Area E (southern part to the KG-Basin, four sites). All 25 sites established during NGHP-02 were first drilled and logged with logging-while-drilling (LWD) tools and an additional 17 holes were then drilled and/or cored with conventional coring tools (HPCS/ESCS) or pressure coring tools (PCTB). Wireline logging was conducted in 10 holes and formation tests using a dual packer Modular Formation Dynamics Tester (MDT) tool were carried out in two holes. The onboard science team used the laboratory facilities on the D/V Chikyu to examine and analyse the physical properties, geochemistry, and sedimentology of all the cores collected during the expedition. Core samples were also analysed in additional post-expedition shore-based studies conducted in numerous domestic and international Gas Hydrate research laboratories. The NGHP-02 sediment cores were archived at the National Gas Hydrate Core Repository in Mumbai (India), which is associated with the ONGC Gas Hydrate Research and Technology Centre (GHRTC). The necessary data for characterizing the occurrence of Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, pressure core and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-02. Almost all the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites established during NGHP-02 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with coarser grained (sand-rich) sediments. This paper presents the operational and technical summary of NGHP-02.
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geologic implications of Gas Hydrates in the offshore of india results of the national Gas Hydrate program expedition 01
Marine and Petroleum Geology, 2014Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, M V Lall, A Mazumdar, M V Ramana, T Ramprasad, Kalachand SainAbstract:Abstract The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of Gas Hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of Gas Hydrate in these two diverse settings. The NGHP-01 expedition established the presence of Gas Hydrates in the Krishna–Godavari and Mahanadi Basins, and the Andaman Sea. The expedition discovered in the Krishna–Godavari Basin one of the thickest Gas Hydrate accumulations ever documented, in the Andaman Sea one of the thickest and deepest Gas Hydrate stability zones in the world, and established the existence of a fully developed Gas Hydrate petroleum system in all three basins. The primary goal of NGHP-01 was to conduct scientific ocean drilling/coring, logging, and analytical activities to assess the geologic occurrence, regional context, and characteristics of Gas Hydrate deposits along the continental margins of India. This was done in order to meet the long-term goal of exploiting Gas Hydrate as a potential energy resource in a cost effective and safe manner. During its 113.5-day voyage, the D/V JOIDES Resolution cored and/or drilled 39 holes at 21 sites (1 site in Kerala–Konkan, 15 sites in Krishna–Godavari, 4 sites in Mahanadi, and 1 site in the Andaman deep offshore area), penetrated more than 9250 m of sedimentary section, and recovered nearly 2850 m of core. Twelve holes were logged with logging-while-drilling (LWD) tools and an additional 13 holes were wireline logged. The science team utilized extensive on-board laboratory facilities to examine and prepare preliminary reports on the physical properties, geochemistry, and sedimentology of all the data collected prior to the end of the expedition. Samples were also analyzed in additional post-expedition shore-based studies conducted in leading laboratories around the world. One of the specific objectives of this expedition was to test Gas Hydrate formation models and constrain model parameters, especially those that account for the formation of concentrated Gas Hydrate accumulations. The necessary data for characterizing the occurrence of in situ Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-01. Almost all of the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites drilled during NGHP-01 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with the presence of fractures in the sediments, and in some limited cases, by coarser grained (mostly sand-rich) sediments.
Ray Boswell - One of the best experts on this subject based on the ideXlab platform.
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india national Gas Hydrate program expedition 02 summary of scientific results Gas Hydrate systems along the eastern continental margin of india
Marine and Petroleum Geology, 2019Co-Authors: Timothy S Collett, Ray Boswell, Pushpendra Kumar, William F Waite, Krishan Chopra, Sunil Kumar Singh, Yasuhiro Yamada, Norio Tenma, John W Pohlman, Margarita V ZyrianovaAbstract:Abstract The primary objectives of the India National Gas Hydrate Program Expedition 02 (NGHP-02) were to obtain new data on the occurrence of Gas Hydrate systems and to advance the understanding of the controls on the formation of Gas Hydrate accumulations in the offshore of India. In accordance with the ultimate overall goal of the NGHP effort to assess the energy resource potential of marine Gas Hydrates in India, particular focus was placed on the exploration and evaluation of Gas Hydrate occurrences at high saturations in sand-rich systems. NGHP-02 operations were conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India and included logging while drilling (LWD) operations at 25 locations, and coring and wireline logging operations at 10 locations, in the Krishna-Godavari and Mahanadi Basins. The formation of highly concentrated Gas Hydrate accumulations, which are more suitable for energy extraction, requires the presence of relatively coarse-grained sediments with porosity needed to support the migration and accumulation of Gas, and the nucleation of Gas Hydrate. The results of downhole logging, coring and formation pressure testing operations during NGHP-02 have confirmed the presence of extensive sand-rich depositional systems throughout the deepwater portions of the Krishna-Godavari and Mahanadi Basins. Two areas of the Krishna-Godavari Basin, referred to as Areas B and C, contain substantial Gas Hydrate accumulations in sand-rich systems and therefore represent ideal candidate sites for future Gas Hydrate production testing. This summary and technical report includes a comprehensive synthesis of the geologic, geophysical, geochemical, and physical property data acquired during NGHP-02 as it relates to the controls on Gas Hydrate occurrence, particularly with regards to sand-hosted accumulations. In the Mahanadi Basin, despite the confirmation of extensive reservoir capacity, Gas supply at the NGHP-02 sites was insufficient to charge the reservoirs with Gas Hydrates. In the Krishna-Godavari Basin, extensive reservoir systems were confirmed with sediment grain-sizes ranging from coarse-silts to gravels. These reservoirs range from fully- to partially-filled with Gas Hydrate. The Gas is determined to be from only microbial sources, and in part migrated into the reservoirs from deeper systems. The controls on Gas Hydrate occurrence are complex and varied; and include substantial reservoir heterogeneity and sufficient permeability throughout the reservoirs and seals that allowed pervasive fluid flow into and through the Hydrate-bearing systems. These discoveries are the most significant confirmation of the exploration approach that focuses on direct detection of Hydrate reservoirs supported by comprehensive petroleum systems analyses.
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geologic implications of Gas Hydrates in the offshore of india results of the national Gas Hydrate program expedition 01
Marine and Petroleum Geology, 2014Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, M V Lall, A Mazumdar, M V Ramana, T Ramprasad, Kalachand SainAbstract:Abstract The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of Gas Hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of Gas Hydrate in these two diverse settings. The NGHP-01 expedition established the presence of Gas Hydrates in the Krishna–Godavari and Mahanadi Basins, and the Andaman Sea. The expedition discovered in the Krishna–Godavari Basin one of the thickest Gas Hydrate accumulations ever documented, in the Andaman Sea one of the thickest and deepest Gas Hydrate stability zones in the world, and established the existence of a fully developed Gas Hydrate petroleum system in all three basins. The primary goal of NGHP-01 was to conduct scientific ocean drilling/coring, logging, and analytical activities to assess the geologic occurrence, regional context, and characteristics of Gas Hydrate deposits along the continental margins of India. This was done in order to meet the long-term goal of exploiting Gas Hydrate as a potential energy resource in a cost effective and safe manner. During its 113.5-day voyage, the D/V JOIDES Resolution cored and/or drilled 39 holes at 21 sites (1 site in Kerala–Konkan, 15 sites in Krishna–Godavari, 4 sites in Mahanadi, and 1 site in the Andaman deep offshore area), penetrated more than 9250 m of sedimentary section, and recovered nearly 2850 m of core. Twelve holes were logged with logging-while-drilling (LWD) tools and an additional 13 holes were wireline logged. The science team utilized extensive on-board laboratory facilities to examine and prepare preliminary reports on the physical properties, geochemistry, and sedimentology of all the data collected prior to the end of the expedition. Samples were also analyzed in additional post-expedition shore-based studies conducted in leading laboratories around the world. One of the specific objectives of this expedition was to test Gas Hydrate formation models and constrain model parameters, especially those that account for the formation of concentrated Gas Hydrate accumulations. The necessary data for characterizing the occurrence of in situ Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-01. Almost all of the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites drilled during NGHP-01 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with the presence of fractures in the sediments, and in some limited cases, by coarser grained (mostly sand-rich) sediments.
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review of progress in evaluating Gas Hydrate drilling hazards
Marine and Petroleum Geology, 2012Co-Authors: Daniel R Mcconnell, Zijian Zhang, Ray BoswellAbstract:Abstract Shallow drilling hazard assessment consists of geological/geophysical review of drill sites to enable the avoidance or effective mitigation of problems that can affect the safe drilling of the “top-hole” section of wells. Primary seafloor hazards include infrastructure, hardgrounds, chemosynthetic communities, and areas of high slope or potential seafloor instability. Shallow subsurface hazards include strata that may contain overpressured water, free Gas, or Gas Hydrate. Among these issues, the potential hazards posed by Gas Hydrate have historically been the most difficult to quantify and constrain. This paper reviews the history of Gas Hydrate shallow hazard assessment, much of which has been framed by difficulties in remote detection and quantification of typical low-saturation, mud-hosted Hydrate occurrences. Recent drilling results indicate that such accumulations can be safely drilled using existing industry protocols. However, assessment of drilling hazards associated with high saturation, sand-hosted Hydrates warrant further investigation, and therefore was a key focus of the Gulf of Mexico Gas Hydrate Joint Industry Project Leg II (JIP Leg II) program conducted in 2009. Pre-drill site hazard assessment for JIP Leg II utilized standard industry methods in which geohazards associated with Gas Hydrate and free Gas were identified in a primarily-qualitative manner using seismic amplitude analysis, seismic stratigraphic interpretation, and geo-pressure analysis. While these methods can reliably detect shallow hydrocarbons, including highly-concentrated Gas Hydrates, they are not sufficient to determine if free Gas may exist below Gas Hydrate, particularly where they occur in close vertical succession. Such undetected free Gas occurrences can pose potential drilling hazards that can be quantitatively assessed using advanced seismic methods.
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current perspectives on Gas Hydrate resources
Energy and Environmental Science, 2011Co-Authors: Ray Boswell, Timothy S CollettAbstract:For the past three decades, discussion of naturally-occurring Gas Hydrates has been framed by a series of assessments that indicate enormous global volumes of methane present within Gas Hydrate accumulations. At present, these estimates continue to range over several orders of magnitude, creating great uncertainty in assessing those two Gas Hydrate issues that relate most directly to resource volumes – Gas Hydrate’s potential as an energy resource and its possible role in ongoing climate change. However, a series of recent field expeditions have provided new insights into the nature of Gas Hydrate occurrence; perhaps most notably, the understanding that Gas Hydrates occur in a wide variety of geologic settings and modes of occurrence. These fundamental differences - which include Gas Hydrate concentration, host lithology, distribution within the sediment matrix, burial depth, water depth, and many others - can now be incorporated into evaluations of Gas Hydrate energy resource and environmental issues. With regard to energy supply potential, field data combined with advanced numerical simulation have identified Gas-Hydrate-bearing sands as the most feasible initial targets for energy recovery. The first assessments of potential technically-recoverable resources are now occurring, enabling a preliminary estimate of ultimate global recoverable volumes on the order of ~3 × 1014 m3 (1016 ft3; ∼150 GtC). Other occurrences, such as Gas Hydrate-filled fractures in clay-dominated reservoirs, may also become potential energy production targets in the future; but as yet, no production concept has been demonstrated. With regard to the climate implications of Gas Hydrate, an analogous partitioning of global resources to determine that portion most prone to dissociation during specific future warming scenarios is needed. At present, it appears that these two portions of total Gas Hydrate resources (those that are the most likely targets for Gas extraction and those that are the most likely to respond in a meaningful way to climate change) will be largely exclusive, as those deposits that are the most amenable to production (the more deeply buried and localized accumulations) are also those that are the most poorly coupled to oceanic and atmospheric conditions.
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permafrost associated natural Gas Hydrate occurrences on the alaska north slope
Marine and Petroleum Geology, 2011Co-Authors: Timothy S Collett, Margarita V Zyrianova, Ray Boswell, W F Agena, John J Miller, Kristen A Lewis, Tanya L InksAbstract:Abstract In the 1960s Russian scientists made what was then a bold assertion that Gas Hydrates should occur in abundance in nature. Since this early start, the scientific foundation has been built for the realization that Gas Hydrates are a global phenomenon, occurring in permafrost regions of the arctic and in deep water portions of most continental margins worldwide. In 1995, the U.S. Geological Survey made the first systematic assessment of the in-place natural Gas Hydrate resources of the United States. That study suggested that the amount of Gas in the Gas Hydrate accumulations of northern Alaska probably exceeds the volume of known conventional Gas resources on the North Slope. Researchers have long speculated that Gas Hydrates could eventually become a producible energy resource, yet technical and economic hurdles have historically made Gas Hydrate development a distant goal. This view began to change in recent years with the realization that this unconventional resource could be developed with existing conventional oil and Gas production technology. One of the most significant developments was the completion of the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well on the Alaska North Slope, which along with the Mallik project in Canada, have for the first time allowed the rational assessment of Gas Hydrate production technology and concepts. Almost 40 years of Gas Hydrate research in northern Alaska has confirmed the occurrence of at least two large Gas Hydrate accumulations on the North Slope. We have also seen in Alaska the first ever assessment of how much Gas could be technically recovered from Gas Hydrates. However, significant technical concerns need to be further resolved in order to assess the ultimate impact of Gas Hydrate energy resource development in northern Alaska.
Margarita V Zyrianova - One of the best experts on this subject based on the ideXlab platform.
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india national Gas Hydrate program expedition 02 summary of scientific results Gas Hydrate systems along the eastern continental margin of india
Marine and Petroleum Geology, 2019Co-Authors: Timothy S Collett, Ray Boswell, Pushpendra Kumar, William F Waite, Krishan Chopra, Sunil Kumar Singh, Yasuhiro Yamada, Norio Tenma, John W Pohlman, Margarita V ZyrianovaAbstract:Abstract The primary objectives of the India National Gas Hydrate Program Expedition 02 (NGHP-02) were to obtain new data on the occurrence of Gas Hydrate systems and to advance the understanding of the controls on the formation of Gas Hydrate accumulations in the offshore of India. In accordance with the ultimate overall goal of the NGHP effort to assess the energy resource potential of marine Gas Hydrates in India, particular focus was placed on the exploration and evaluation of Gas Hydrate occurrences at high saturations in sand-rich systems. NGHP-02 operations were conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India and included logging while drilling (LWD) operations at 25 locations, and coring and wireline logging operations at 10 locations, in the Krishna-Godavari and Mahanadi Basins. The formation of highly concentrated Gas Hydrate accumulations, which are more suitable for energy extraction, requires the presence of relatively coarse-grained sediments with porosity needed to support the migration and accumulation of Gas, and the nucleation of Gas Hydrate. The results of downhole logging, coring and formation pressure testing operations during NGHP-02 have confirmed the presence of extensive sand-rich depositional systems throughout the deepwater portions of the Krishna-Godavari and Mahanadi Basins. Two areas of the Krishna-Godavari Basin, referred to as Areas B and C, contain substantial Gas Hydrate accumulations in sand-rich systems and therefore represent ideal candidate sites for future Gas Hydrate production testing. This summary and technical report includes a comprehensive synthesis of the geologic, geophysical, geochemical, and physical property data acquired during NGHP-02 as it relates to the controls on Gas Hydrate occurrence, particularly with regards to sand-hosted accumulations. In the Mahanadi Basin, despite the confirmation of extensive reservoir capacity, Gas supply at the NGHP-02 sites was insufficient to charge the reservoirs with Gas Hydrates. In the Krishna-Godavari Basin, extensive reservoir systems were confirmed with sediment grain-sizes ranging from coarse-silts to gravels. These reservoirs range from fully- to partially-filled with Gas Hydrate. The Gas is determined to be from only microbial sources, and in part migrated into the reservoirs from deeper systems. The controls on Gas Hydrate occurrence are complex and varied; and include substantial reservoir heterogeneity and sufficient permeability throughout the reservoirs and seals that allowed pervasive fluid flow into and through the Hydrate-bearing systems. These discoveries are the most significant confirmation of the exploration approach that focuses on direct detection of Hydrate reservoirs supported by comprehensive petroleum systems analyses.
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gulf of mexico Gas Hydrate joint industry project leg ii logging while drilling data acquisition and analysis
Marine and Petroleum Geology, 2012Co-Authors: Timothy S Collett, Margarita V Zyrianova, Stefan Mrozewski, Gilles Guerin, Ann E Cook, Dave GoldbergAbstract:Abstract One of the objectives of the Gulf of Mexico Gas Hydrate Joint Industry Project Leg II (GOM JIP Leg II) was the collection of a comprehensive suite of logging-while-drilling (LWD) data within Gas-Hydrate-bearing sand reservoirs in order to make accurate estimates of the concentration of Gas Hydrates under various geologic conditions and to understand the geologic controls on the occurrence of Gas Hydrate at each of the sites drilled during this expedition. The LWD sensors just above the drill bit provided important information on the nature of the sediments and the occurrence of Gas Hydrate. There has been significant advancements in the use of downhole well-logging tools to acquire detailed information on the occurrence of Gas Hydrate in nature: From using electrical resistivity and acoustic logs to identify Gas Hydrate occurrences in wells to where wireline and advanced logging-while-drilling tools are routinely used to examine the petrophysical nature of Gas Hydrate reservoirs and the distribution and concentration of Gas Hydrates within various complex reservoir systems. Recent integrated sediment coring and well-log studies have confirmed that electrical resistivity and acoustic velocity data can yield accurate Gas Hydrate saturations in sediment grain supported (isotropic) systems such as sand reservoirs, but more advanced log analysis models are required to characterize Gas Hydrate in fractured (anisotropic) reservoir systems. In support of the GOM JIP Leg II effort, well-log data montages have been compiled and presented in this report which includes downhole logs obtained from all seven wells drilled during this expedition with a focus on identifying and characterizing the potential Gas-Hydrate-bearing sedimentary section in each of the wells. Also presented and reviewed in this report are the Gas-Hydrate saturation and sediment porosity logs for each of the wells as calculated from available downhole well logs.
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permafrost associated natural Gas Hydrate occurrences on the alaska north slope
Marine and Petroleum Geology, 2011Co-Authors: Timothy S Collett, Margarita V Zyrianova, Ray Boswell, W F Agena, John J Miller, Kristen A Lewis, Tanya L InksAbstract:Abstract In the 1960s Russian scientists made what was then a bold assertion that Gas Hydrates should occur in abundance in nature. Since this early start, the scientific foundation has been built for the realization that Gas Hydrates are a global phenomenon, occurring in permafrost regions of the arctic and in deep water portions of most continental margins worldwide. In 1995, the U.S. Geological Survey made the first systematic assessment of the in-place natural Gas Hydrate resources of the United States. That study suggested that the amount of Gas in the Gas Hydrate accumulations of northern Alaska probably exceeds the volume of known conventional Gas resources on the North Slope. Researchers have long speculated that Gas Hydrates could eventually become a producible energy resource, yet technical and economic hurdles have historically made Gas Hydrate development a distant goal. This view began to change in recent years with the realization that this unconventional resource could be developed with existing conventional oil and Gas production technology. One of the most significant developments was the completion of the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well on the Alaska North Slope, which along with the Mallik project in Canada, have for the first time allowed the rational assessment of Gas Hydrate production technology and concepts. Almost 40 years of Gas Hydrate research in northern Alaska has confirmed the occurrence of at least two large Gas Hydrate accumulations on the North Slope. We have also seen in Alaska the first ever assessment of how much Gas could be technically recovered from Gas Hydrates. However, significant technical concerns need to be further resolved in order to assess the ultimate impact of Gas Hydrate energy resource development in northern Alaska.
Michael Riedel - One of the best experts on this subject based on the ideXlab platform.
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Seismic AVO for Gas-Hydrate-Related Reflections
Geophysical Characterization of Gas Hydrates, 2020Co-Authors: Marc-andré P. Chen, Michael Riedel, Stan E. DossoAbstract:This paper examines the usefulness of amplitude versus offset (AVO) analysis for marine and permafrost Gas Hydrate settings. In marine environments, AVO analyses have traditionally focused on bottom-simulating reflections (BSRs) for estimating associated marine Gas Hydrate and free Gas concentrations. A nonlinear Bayesian inversion is applied to estimate marginal probability distributions (MPDs) of physical parameters at a BSR interface, which are related to overlying Gas Hydrate and underlying free-Gas concentrations via rock physics modeling. The problem is further constrained by prior information and re-parameterization of inversion results. Inversion of BSR AVO data from offshore Vancouver Island, Canada, shows that Gas Hydrate and free-Gas concentrations are, respectively, 0-23% and 0-2% of the pore volume, at a 90% credibility level. However, it should be noted that these two parameters are not independent in the analysis, but instead inversely related. Thus, 0% in Gas Hydrate concentrations requires some percent of free Gas within the range stated (and vice versa). This result indicates that the data do not provide sufficient information to independently resolve Gas Hydrate and free-Gas concentrations to useful accuracy. The same Bayesian inversion method is applied to synthetic AVO data generated from well-log data obtained at the Mallik 5L-38 well in the Mckenzie Delta, NWT. The model cases representing typical permafrost Gas Hydrate occurrences are investigated and include shale over Gas Hydrate-bearing sand, Gas Hydrate-bearing sand over shale, and Gas Hydrate-bearing sand over water-saturated sand scenarios. The AVO inversion sufficiently constrains the shear-wave velocity for reliable quantitative analysis, only if the Gas Hydrate concentration exceeds ~40%. The variable degree of model constraint obtained in this AVO study highlights the need to include rigorous quantitative uncertainty analysis in all AVO studies.
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geologic implications of Gas Hydrates in the offshore of india results of the national Gas Hydrate program expedition 01
Marine and Petroleum Geology, 2014Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, M V Lall, A Mazumdar, M V Ramana, T Ramprasad, Kalachand SainAbstract:Abstract The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of Gas Hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of Gas Hydrate in these two diverse settings. The NGHP-01 expedition established the presence of Gas Hydrates in the Krishna–Godavari and Mahanadi Basins, and the Andaman Sea. The expedition discovered in the Krishna–Godavari Basin one of the thickest Gas Hydrate accumulations ever documented, in the Andaman Sea one of the thickest and deepest Gas Hydrate stability zones in the world, and established the existence of a fully developed Gas Hydrate petroleum system in all three basins. The primary goal of NGHP-01 was to conduct scientific ocean drilling/coring, logging, and analytical activities to assess the geologic occurrence, regional context, and characteristics of Gas Hydrate deposits along the continental margins of India. This was done in order to meet the long-term goal of exploiting Gas Hydrate as a potential energy resource in a cost effective and safe manner. During its 113.5-day voyage, the D/V JOIDES Resolution cored and/or drilled 39 holes at 21 sites (1 site in Kerala–Konkan, 15 sites in Krishna–Godavari, 4 sites in Mahanadi, and 1 site in the Andaman deep offshore area), penetrated more than 9250 m of sedimentary section, and recovered nearly 2850 m of core. Twelve holes were logged with logging-while-drilling (LWD) tools and an additional 13 holes were wireline logged. The science team utilized extensive on-board laboratory facilities to examine and prepare preliminary reports on the physical properties, geochemistry, and sedimentology of all the data collected prior to the end of the expedition. Samples were also analyzed in additional post-expedition shore-based studies conducted in leading laboratories around the world. One of the specific objectives of this expedition was to test Gas Hydrate formation models and constrain model parameters, especially those that account for the formation of concentrated Gas Hydrate accumulations. The necessary data for characterizing the occurrence of in situ Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-01. Almost all of the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites drilled during NGHP-01 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with the presence of fractures in the sediments, and in some limited cases, by coarser grained (mostly sand-rich) sediments.
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geothermal modeling for the base of Gas Hydrate stability zone and saturation of Gas Hydrate in the krishna godavari basin eastern indian margin
Journal of The Geological Society of India, 2012Co-Authors: Uma Shankar, Kalachand Sain, Michael RiedelAbstract:The passive eastern Indian margin is rich in Gas Hydrates, as inferred from the wide-spread occurrences of bottom-simulating reflectors (BSRs) and recovery of Gas Hydrate samples from various sites in the Krishna Godavari (KG) and Mahanadi (MN) basins drilled by the Expedition 01 of the Indian National Gas Hydrate Program (NGHP). The BSRs are often interpreted to mark the thermally controlled base of Gas Hydrate stability zone (BGHSZ). Most of the BSRs exhibit moderate to typically higher amplitudes than those from other seismic reflectors. We estimate the average geothermal gradient of ∼40°C/km and heat flow varying from 23 to 62 mW/m2 in the study area utilizing the BSR’s observed on seismic sections. Further we provide the BGHSZ where the BSR is not continuous or disturbed by local tectonics or hidden by sedimentation patterns parallel to the seafloor with a view to understand the nature of BSR.
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Geothermal modeling of the Gas Hydrate stability zone along the Krishna Godavari Basin
Marine Geophysical Researches, 2010Co-Authors: Uma Shankar, Michael Riedel, A. V. SatheAbstract:A wide-spread bottom simulating reflector (BSR), interpreted to mark the thermally controlled base of the Gas Hydrate stability zone, is observed over a close grid of multichannel seismic profiles in the Krishna Godavari Basin of the eastern continental margin of India. The seismic data reveal that Gas Hydrate occurs in the Krishna Godavari Basin at places where water depths exceed 850 m. The thickness of the Gas Hydrate stability zone inferred from the BSR ranges up to 250 m. A conductive model was used to determine geothermal gradients and heat flow. Ground truth for the assessment and constraints on the model were provided by downhole measurements obtained during the National Gas Hydrate Program Expedition 01 of India at various sites in the Krishna Godavari Basin. Measured downhole temperature gradients and seafloor-temperatures, sediment thermal conductivities, and seismic velocity are utilized to generate regression functions for these parameters as function of overall water depth. In the first approach the base of Gas Hydrate stability is predicted from seafloor bathymetry using these regression functions and heat flow and geothermal gradient are calculated. In a second approach the observed BSR depth from the seismic profiles (measured in two-way travel time) is converted into heat flow and geothermal gradient using the same ground-truth data. The geothermal gradient estimated from the BSR varies from 27 to 67°C/km. Corresponding heat flow values range from 24 to 60 mW/m^2. The geothermal modeling shows a close match of the predicted base of the Gas Hydrate stability zone with the observed BSR depths.
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INDIAN CONTINENTAL MARGIN Gas Hydrate PROSPECTS: RESULTS OF THE INDIAN NATIONAL Gas Hydrate PROGRAM (NGHP) EXPEDITION 01
2008Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, A. V. SatheAbstract: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 controls on the occurrence of Gas Hydrate in these two diverse settings. NGHP Expedition 01 established the presence of Gas Hydrates in KrishnaGodavari, Mahanadi and Andaman basins. The expedition discovered one of the richest Gas Hydrate accumulations yet documented (Site 10 in the Krishna-Godavari Basin), documented the thickest and deepest Gas Hydrate stability zone yet known (Site 17 in Andaman Sea), and established the existence of a fully-developed Gas Hydrate system in the Mahanadi Basin (Site 19).
Pushpendra Kumar - One of the best experts on this subject based on the ideXlab platform.
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india national Gas Hydrate program expedition 02 operational and technical summary
Marine and Petroleum Geology, 2019Co-Authors: Pushpendra Kumar, Timothy S Collett, K M Shukla, U S Yadav, M V Lall, Krishna VishwanathAbstract:Abstract The India National Gas Hydrate Program is being steered by the government of India's Ministry of Petroleum and Natural Gas (MoPNG) with participation of Directorate General of Hydrocarbons (DGH), Oil and Natural Gas Corporation Limited (ONGC), and the National Oil Companies and Research Institutes of India. The India National Gas Hydrate Program Expedition 01 (NGHP-01) established the presence of Gas Hydrate in the Krishna Godavari (KG) and Mahanadi Basins and in the offshore area of the Andaman Sea Basin. However, the Gas Hydrates discovered during NGHP-01 were mainly distributed as fracture-filling material in fine-grained clay-rich sediments. The India National Gas Hydrate Program Expedition 02 (NGHP-02) was carried out with an objective to discover Gas Hydrate in sand-rich sediment along the eastern offshore margin of India. ONGC planned and executed NGHP-02 on the behalf of the MoPNG. NGHP-02 started on March 3, 2015 and was completed on July 28, 2015 (total 147 days) using the Japanese scientific Drilling Vessel Chikyu (D/V Chikyu). During NGHP-02, 42 holes at 25 sites were drilled, cored, and/or surveyed with downhole logging tools. These sites were located in four areas along the eastern margin of India and formally named Area A (Mahanadi Basin, three sites), Area B (northern part of the KG-Basin, twelve sites), Area C (central part of the KG-Basin, six sites), and Area E (southern part to the KG-Basin, four sites). All 25 sites established during NGHP-02 were first drilled and logged with logging-while-drilling (LWD) tools and an additional 17 holes were then drilled and/or cored with conventional coring tools (HPCS/ESCS) or pressure coring tools (PCTB). Wireline logging was conducted in 10 holes and formation tests using a dual packer Modular Formation Dynamics Tester (MDT) tool were carried out in two holes. The onboard science team used the laboratory facilities on the D/V Chikyu to examine and analyse the physical properties, geochemistry, and sedimentology of all the cores collected during the expedition. Core samples were also analysed in additional post-expedition shore-based studies conducted in numerous domestic and international Gas Hydrate research laboratories. The NGHP-02 sediment cores were archived at the National Gas Hydrate Core Repository in Mumbai (India), which is associated with the ONGC Gas Hydrate Research and Technology Centre (GHRTC). The necessary data for characterizing the occurrence of Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, pressure core and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-02. Almost all the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites established during NGHP-02 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with coarser grained (sand-rich) sediments. This paper presents the operational and technical summary of NGHP-02.
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india national Gas Hydrate program expedition 02 summary of scientific results Gas Hydrate systems along the eastern continental margin of india
Marine and Petroleum Geology, 2019Co-Authors: Timothy S Collett, Ray Boswell, Pushpendra Kumar, William F Waite, Krishan Chopra, Sunil Kumar Singh, Yasuhiro Yamada, Norio Tenma, John W Pohlman, Margarita V ZyrianovaAbstract:Abstract The primary objectives of the India National Gas Hydrate Program Expedition 02 (NGHP-02) were to obtain new data on the occurrence of Gas Hydrate systems and to advance the understanding of the controls on the formation of Gas Hydrate accumulations in the offshore of India. In accordance with the ultimate overall goal of the NGHP effort to assess the energy resource potential of marine Gas Hydrates in India, particular focus was placed on the exploration and evaluation of Gas Hydrate occurrences at high saturations in sand-rich systems. NGHP-02 operations were conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India and included logging while drilling (LWD) operations at 25 locations, and coring and wireline logging operations at 10 locations, in the Krishna-Godavari and Mahanadi Basins. The formation of highly concentrated Gas Hydrate accumulations, which are more suitable for energy extraction, requires the presence of relatively coarse-grained sediments with porosity needed to support the migration and accumulation of Gas, and the nucleation of Gas Hydrate. The results of downhole logging, coring and formation pressure testing operations during NGHP-02 have confirmed the presence of extensive sand-rich depositional systems throughout the deepwater portions of the Krishna-Godavari and Mahanadi Basins. Two areas of the Krishna-Godavari Basin, referred to as Areas B and C, contain substantial Gas Hydrate accumulations in sand-rich systems and therefore represent ideal candidate sites for future Gas Hydrate production testing. This summary and technical report includes a comprehensive synthesis of the geologic, geophysical, geochemical, and physical property data acquired during NGHP-02 as it relates to the controls on Gas Hydrate occurrence, particularly with regards to sand-hosted accumulations. In the Mahanadi Basin, despite the confirmation of extensive reservoir capacity, Gas supply at the NGHP-02 sites was insufficient to charge the reservoirs with Gas Hydrates. In the Krishna-Godavari Basin, extensive reservoir systems were confirmed with sediment grain-sizes ranging from coarse-silts to gravels. These reservoirs range from fully- to partially-filled with Gas Hydrate. The Gas is determined to be from only microbial sources, and in part migrated into the reservoirs from deeper systems. The controls on Gas Hydrate occurrence are complex and varied; and include substantial reservoir heterogeneity and sufficient permeability throughout the reservoirs and seals that allowed pervasive fluid flow into and through the Hydrate-bearing systems. These discoveries are the most significant confirmation of the exploration approach that focuses on direct detection of Hydrate reservoirs supported by comprehensive petroleum systems analyses.
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geologic implications of Gas Hydrates in the offshore of india results of the national Gas Hydrate program expedition 01
Marine and Petroleum Geology, 2014Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, M V Lall, A Mazumdar, M V Ramana, T Ramprasad, Kalachand SainAbstract:Abstract The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of Gas Hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of Gas Hydrate in these two diverse settings. The NGHP-01 expedition established the presence of Gas Hydrates in the Krishna–Godavari and Mahanadi Basins, and the Andaman Sea. The expedition discovered in the Krishna–Godavari Basin one of the thickest Gas Hydrate accumulations ever documented, in the Andaman Sea one of the thickest and deepest Gas Hydrate stability zones in the world, and established the existence of a fully developed Gas Hydrate petroleum system in all three basins. The primary goal of NGHP-01 was to conduct scientific ocean drilling/coring, logging, and analytical activities to assess the geologic occurrence, regional context, and characteristics of Gas Hydrate deposits along the continental margins of India. This was done in order to meet the long-term goal of exploiting Gas Hydrate as a potential energy resource in a cost effective and safe manner. During its 113.5-day voyage, the D/V JOIDES Resolution cored and/or drilled 39 holes at 21 sites (1 site in Kerala–Konkan, 15 sites in Krishna–Godavari, 4 sites in Mahanadi, and 1 site in the Andaman deep offshore area), penetrated more than 9250 m of sedimentary section, and recovered nearly 2850 m of core. Twelve holes were logged with logging-while-drilling (LWD) tools and an additional 13 holes were wireline logged. The science team utilized extensive on-board laboratory facilities to examine and prepare preliminary reports on the physical properties, geochemistry, and sedimentology of all the data collected prior to the end of the expedition. Samples were also analyzed in additional post-expedition shore-based studies conducted in leading laboratories around the world. One of the specific objectives of this expedition was to test Gas Hydrate formation models and constrain model parameters, especially those that account for the formation of concentrated Gas Hydrate accumulations. The necessary data for characterizing the occurrence of in situ Gas Hydrate, such as interstitial water chlorinities, core-derived Gas chemistry, physical and sedimentological properties, thermal images of the recovered cores, and downhole measured logging data (LWD and/or conventional wireline log data), were obtained from most of the drill sites established during NGHP-01. Almost all of the drill sites yielded evidence for the occurrence of Gas Hydrate; however, the inferred in situ concentration of Gas Hydrate varied substantially from site to site. For the most part, the interpretation of downhole logging data, core thermal images, interstitial water analyses, and pressure core images from the sites drilled during NGHP-01 indicate that the occurrence of concentrated Gas Hydrate is mostly associated with the presence of fractures in the sediments, and in some limited cases, by coarser grained (mostly sand-rich) sediments.
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INDIAN CONTINENTAL MARGIN Gas Hydrate PROSPECTS: RESULTS OF THE INDIAN NATIONAL Gas Hydrate PROGRAM (NGHP) EXPEDITION 01
2008Co-Authors: Timothy S Collett, Michael Riedel, James R. Cochran, Ray Boswell, Pushpendra Kumar, A. V. SatheAbstract: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 controls on the occurrence of Gas Hydrate in these two diverse settings. NGHP Expedition 01 established the presence of Gas Hydrates in KrishnaGodavari, Mahanadi and Andaman basins. The expedition discovered one of the richest Gas Hydrate accumulations yet documented (Site 10 in the Krishna-Godavari Basin), documented the thickest and deepest Gas Hydrate stability zone yet known (Site 17 in Andaman Sea), and established the existence of a fully-developed Gas Hydrate system in the Mahanadi Basin (Site 19).
