Download or read book Sensitivity of Seismic Responses to Gas Hydrates written by United States. Department of Energy and published by . This book was released on 1992 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Sensitivity of Seismic Responses to Gas Hydrates written by and published by . This book was released on 1992 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary goal of this project was to determine the sensitivity of seismic responses to gas hydrate and associated free gas saturation within marine sediments. The development of a model to predict the physical properties of sediments containing hydrates was required. This model was used as the basis for predicting the sensitivity of P and S wave seismic velocities and waveform amplitudes to variations in hydrate and free gas saturation. Secondary goals of the project included: assessment of the usefulness of seismic shear waves in characterizing hydrate saturation and a review of potential complications in seismic modeling procedures.

Download or read book The Sensitivity of Seismic Responses to Gas Hydrates Final Report written by and published by . This book was released on 1992 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sensitivity of seismic reflection coefficients and amplitudes, and their variations with changing incidence angles and offsets, was determined with respect to changes in the parameters which characterize marine sediments containing gas hydrates. Using the results of studies of ice saturation effects in permafrost soils, we have introduced rheological effects of hydrate saturation. The replacement of pore fluids in highly porous and unconsolidated marine sediments with crystalline gas hydrates, increases the rigidity of the sediments, and alters the ratio of compressional/shear strength ratio. This causes Vp/Vs ratio variations which have an effect on the amplitudes of P-wave and S-wave reflections. Analysis of reflection coefficient functions has revealed that amplitudes are very sensitive to porosity estimates, and errors in the assumed model porosity can effect the estimates of hydrate saturation. Additionally, we see that the level of free gas saturation is difficult to determine. A review of the effects of free gas and hydrate saturation on shear wave arrivals indicates that far-offset P to S wave converted arrivals may provide a means of characterizing hydrate saturations. Complications in reflection coefficient and amplitude modelling can arise from gradients in hydrate saturation levels and from rough sea floor topography. An increase in hydrate saturation with depth in marine sediments causes rays to bend towards horizontal and increases the reflection incidence angles and subsequent amplitudes. This effect is strongly accentuated when the vertical separation between the source and the hydrate reflection horizon is reduced. The effect on amplitude variations with offset due to a rough sea floor was determined through finite difference wavefield modelling. Strong diffractions in the waveforms add noise to the amplitude versus offset functions.

Download or read book Geophysical Characterization of Gas Hydrates written by Michael Riedel and published by . This book was released on 2010 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of gas hydrates in large quantities worldwide, and their immense energy potential have prompted concerted efforts into their exploration and understanding over the last many years. During this time, geophysical characterization of natural gas hydrate occurrences by seismic and other methods have gained prominence, and such studies have been reported from time to time. However, no compilation of such studies was ever attempted. This SEG publication, Geophysical Characterization of Gas Hydrates (Geophysical Developments No. 14), is the first book on the topic that focuses on documenting various types of geophysical studies that are carried out for the detection and mapping of gas hydrates.

Download or read book S 33 and H R 1753 the Methane Hydrate Research and Development Act of 1999 written by United States. Congress. House. Committee on Science. Subcommittee on Energy and Environment and published by . This book was released on 1999 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book S 1418 the Methane Hydrate Research and Development Act of 1998 written by United States. Congress. House. Committee on Science. Subcommittee on Energy and Environment and published by . This book was released on 1999 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Basin and Petroleum System Modeling and Global Sensitivity Analyses of Natural Gas Hydrates written by Laura Dafov and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: (I) Topics are broadly defined then followed by chapter highlights: Gas hydrate is a solid, ice-like, form of natural gas that is found in the low temperature, high pressure conditions of shallow sediment in deep marine environments and in permafrost regions. This solid form of natural gas is extensively found offshore every continent on Earth and potentially has a greater amount of energy than all other forms of oil, gas, and coal combined. Therefore, it is of interest for industry, academia, and government sectors, particularly for nations that have limited domestic natural gas resources. Gas hydrates tie in with CO2 sequestration or storage, energy resources, the global carbon cycle, and geohazards. Basin and petroleum system modeling is a quantitative algorithmic approach that utilizes diverse datasets including, but not limited to, well logs, paleontology, stratigraphy, petrophysics, and seismic data to make deterministic, iterative, forward-modeling predictions. It integrates geology, geophysics, geochemistry, engineering, geostatistics, and rock physics to model the sedimentary and tectonic evolution of basins, as well as to model and predict the generation, migration, and accumulation of hydrocarbons in up to three dimensions through geologic time. Though widely used for the modeling of conventional oil and gas systems, basin and petroleum system modeling only recently has been used to study gas hydrate systems, with the first non-proprietary gas hydrate basin and petroleum system model published in 2015. Sensitivity analysis is the study of how variation of uncertain input parameters impacts the response of interest and has great potential application to basin and petroleum system modeling of gas hydrates. A couple of strengths of sensitivity analysis are that it helps determine which data are most important to acquire for reducing uncertainty and it can help simplify a complex problem by identifying less important input parameters. Local sensitivity analysis is a one-at-a-time sensitivity analysis technique that analyzes the effect of one parameter on a function at a time, keeping the other parameters fixed. It explores only a small fraction of the design space, especially when there are many parameters, and is a simple screening method that is widely used across disciplines. Furthermore, the local sensitivity analysis method does not evaluate parameter interactions for non-linear effects. On the other hand, global sensitivity analysis is a powerful tool that has never before been used for gas hydrate basin and petroleum system modeling despite it being effective at evaluating parameter interactions for non-linear effects. Global sensitivity analysis helps understand and simplify the complexity of problems and elucidates what model variables impact data, decisions, and forecasts. (II) Chapter 1 highlights: We built a detailed (more than 25 million cells) quantitative 3D basin and petroleum system model of Terrebonne Basin, Gulf of Mexico, for dynamic gas hydrate studies and to be used to support planning for scientific drilling. Original interpretations of the geology, using seismic imaging and well logs, are presented, including a proposed mechanism for the presence of giant gas mounds. Our model predicts present-day gas and gas hydrate volumes, saturations and distributions of accumulations, marine gas hydrate recycling (by which gas hydrate saturations at the base of the gas hydrate stability zone increase through time due to, for example, sediment burial), and the potential source of gas in the basin (specifically, thermogenic versus biogenic). The source of gas determines whether light or heavy gases likely exist, which have different economic implications, the latter being more valuable. Our model is calibrated to porosity and pressure data and our model-based gas hydrate saturation predictions align with what is observed in well log and seismic data vertically and laterally. We suggest that our 3D model has application to future studies that seek to understand gas hydrates as they relate to faults, fractures, lithologic variations, salt tectonics, erosion, pressures, changing water column conditions, temperature changes, and gas sources, as these Earth system features have all been incorporated into our model. (III) Chapter 2 highlights: By harnessing theoretical 2D basin and petroleum system models and real-world inspired models based on the well-studied salt diapir-associated gas hydrate sites at Green Canyon (Gulf of Mexico) and Blake Ridge (U.S. Atlantic coast), we demonstrate that salt structures provide a heat flow-driven mechanism for marine gas hydrate recycling that results in enhanced saturations. Our work also provides insight into the roles of basal heat flows, salt diapir diameters, and sediment thermal conductivities in controlling optimal gas hydrate accumulations in salt basins. Broadly speaking, we suggest that gas hydrate and associated gas accumulations above salt diapir crests represent attractive targets for hydrocarbon resource exploration and for scientific drilling expeditions aimed at characterizing these systems. It therefore follows that salt basins are compelling localities for studying our newly proposed mechanism of salt diapir heat flow-driven enhanced gas hydrate and gas accumulations. (IV) Chapter 3 highlights: We developed a widely-applicable, novel automated method that results in thousands of unique 2D basin and petroleum system models of gas hydrates and it applies global sensitivity analysis to them. To put this in perspective, only tens of basin and petroleum system models of gas hydrates have been published. Our work is the first time, at least in the public domain, that global sensitivity analysis has been coupled with basin and petroleum system modeling of gas hydrates. This tool improves the efficiency of basin and petroleum system modeling of gas hydrates by ~40 times, as well as eliminating sampling bias by randomly building models using the Monte Carlo approach. We believe our 2D basin and petroleum system model scenarios, as well as their associated organized databases of 10s of thousands of extracted input and output values, can be used as templates and guides for future basin and petroleum system modeling of gas hydrates and of other hydrocarbon systems. Our work provides insight into the relative importance of different geologic properties when assessing gas hydrate stability zone thicknesses, gas hydrate saturations, and gas saturations by utilizing quantitative and objective measures of sensitivity. Furthermore, this powerful tool reveals important geologic input interactions that cannot otherwise be observed using the traditionally used method of local sensitivity analysis. One of our many geologic takeaways or recommendations is that professionals who plan to explore for gas hydrate accumulations should consider shallow to midwater depths more so than deepwater, because our results show that those basin models are more conducive, geologically, for gas hydrate accumulations that have relatively high saturations. Our two distinct sets of models span a wide range of basin scenarios intended to represent: (1) the entire world and (2) the sites where gas hydrates have been found or inferred. We use these results to answer questions about how to improve global map predictions. Our work provides original plots illustrating the relationship between basal heat flow and the gas hydrate stability zone that could be useful in new ventures or other exploration of conventional petroleum systems where a gas hydrate stability zone is observed or inferred. Basal heat flow is among the least known values when gathering information about a basin. Our plots can be used as a guide to determine what the likely range of basal heat flows is acceptable for a basin, which can result in the difference between generation of oil or gas.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Natural Gas Hydrate in Oceanic and Permafrost Environments written by M.D. Max and published by Springer Science & Business Media. This book was released on 2003-05-31 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book published on the emerging research field of naturally occurring gas hydrates (focusing on methane hydrate) that is not primarily a physical chemistry textbook. This book is designed as a broad introduction to the field of hydrate science, demonstrating the significance of the hydrate cycle to energy resource potential, seafloor stability, and global climate and climate change, along with other issues. The best known hydrate localities are described, as are research and laboratory methods and results. The book consists of chapters grouped in related themes that present up-to-date information on methane hydrate. Each of the contributing authors is expert in hydrate science and most have been carrying out research in hydrate for a considerable time. Audience: This book will be an important source of information for marine geologists, geophysicists, geochemists, and petroleum geologists and regulators. It is also intended as a graduate-level textbook.

Download or read book Rock Physics and Geofluid Detection written by Jing Ba and published by Frontiers Media SA. This book was released on 2021-10-29 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gas Hydrate written by Umberta Tinivella and published by MDPI. This book was released on 2019-11-28 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue reports research spanning from the analysis of indirect data, modeling, and laboratory and geological data confirming the intrinsic multidisciplinarity of gas hydrate studies. The study areas are (1) Arctic, (2) Brazil, (3) Chile, and (4) the Mediterranean region. The results furnished an important tessera of the knowledge about the relationship of a gas hydrate system with other complex natural phenomena such as climate change, slope stability and earthquakes, and human activities.

Download or read book Study of the Electromagnetic Response of Gas Hydrates Using Forward CSEM 1 dimensional Models from Global Gas Hydrate Deposits written by James A. Lindsay and published by . This book was released on 2012 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Exploration of Gas Hydrates written by Naresh Kumar Thakur and published by Springer Science & Business Media. This book was released on 2010-10-08 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates are ice-like crystalline substances that form a rigid cage of water molecules and entrap hydrocarbon and non-hydrocarbon gas by hydrogen bonding. Natural gas hydrate is primarily composed of water and methane. These are solid, crystalline, ice-like substances found in permafrost areas and deepwater basins around the world. They naturally occur in the pore space of marine sediments, where appropriate high pressure and low temperature conditions exist in an adequate supply of gas (mainly methane). Gas hydrates are considered as a potential non conventional energy resource. 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. The proposed book treats various geophysical techniques in order to quantify the gas hydrate reserves and their impact on environment. The primary goal of this book is to provide the state of art for gas hydrate exploration. The target audiences for this book are non-specialist from different branches of science, graduate students and researchers.

Download or read book Petroleum Abstracts written by and published by . This book was released on 1998 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sensitivity of Piping Seismic Responses to Input Factors written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the sensitivity of peak dynamic seismic responses to input parameters. The responses have been modeled and calculated for the Zion Unit 1 plant as part of a seismic probabilistic risk assessment (PRA) performed by the US NRC Seismic Safety Margins Research Program (SSMRP). The SSMRP was supported by the US NRC Office of Nuclear Regulatory Research. Two sensitivity topics motivated the study. The first is the sensitivity of piping response to the mean value of piping damping. The second is the sensitivity of all the responses to the earthquake and model input parameters including soil, structure and piping parameters; this information is required for another study, the sensitivity of the plant system response (in terms of risk) to these dynamic input parameters and to other input factors. We evaluate the response sensitivities by performing a linear regression analysis (LRA) of the computer code SMACS. With SMACS we have a detailed model of the Zion plant and of the important dynamic processes in the soil, structures and piping systems. The qualitative results change with the location of the individual response. Different responses are in locations where the many potential influences have different effectiveness. The results give an overview of the complexity of the seismic dyanmic response of a plant. Within the diversity trends are evident in the influences of the input variables on the responses.

Download or read book Economic Geology of Natural Gas Hydrate written by Michael D. Max and published by Springer Science & Business Media. This book was released on 2006-07-09 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a companion to “Natural Gas Hydrate in Oceanic and Permafrost Environments” (Max, 2000, 2003), which is the first book on gas hydrate in this series. Although other gases can naturally form clathrate hydrates (referred to after as ‘hydrate’), we are concerned here only with hydrocarbon gases that form hydrates. The most important of these natural gases is methane. Whereas the first book is a general introduction to the subject of natural gas hydrate, this book focuses on the geology and geochemical controls of gas hydrate development and on gas extraction from naturally occurring hydrocarbon hydrates. This is the first broad treatment of gas hydrate as a natural resource within an economic geological framework. This book is written mainly to stand alone for brevity and to minimize duplication. Information in Max (2000; 2003) should also be consulted for completeness. Hydrate is a type of clathrate (Sloan, 1998) that is formed from a cage structure of water molecules in which gas molecules occupying void sites within the cages stabilize the structure through van der Waals or hydrogen bonding.