Natural Gas Hydrate


Book Description

1. THE BEGINNINGS OF HYDRATE RESEARCH Until very recently, our understanding of hydrate in the natural environment and its impact on seafloor stability, its importance as a sequester of methane, and its potential as an important mechanism in the Earth's climate change system, was masked by our lack of appreciation of the vastness of the hydrate resource. Only a few publications on naturally occurring hydrate existed prior to 1975. The first published reference to oceanic gas hydrate (Bryan and Markl, 1966) and the first publication in the scientific literature (Stoll, et a1., 1971) show how recently it has been since the topic of naturally occurring hydrate has been raised. Recently, however, the number of hydrate publications has increased substantially, reflecting increased research into hydrate topics and the initiation of funding to support the researchers. Awareness of the existence of naturally occurring gas hydrate now has spread beyond the few scientific enthusiasts who pursued knowledge about the elusive hydrate because of simple interest and lurking suspicions that hydrate would prove to be an important topic. The first national conference on gas hydrate in the U.S. was held as recently as April, 1991 at the U.S. National Center of the U.s. Geological Survey in Reston Virginia (Max et al., 1991). The meeting was co-hosted by the U.s. Geological Survey, the Naval Research Laboratory, and the U.S.




Geological Controls for Gas Hydrates and Unconventionals


Book Description

Geological Controls for Gas Hydrate Formations and Unconventionals tells the story of unconventional hydrocarbon resources, especially gas hydrates, tight gas, shale gas, liquid- rich shale, and shale oil, to future generations. It presents the most current research in unconventionals, covering structural constituents of continental margins and their role in generating hydrocarbons. Additionally, this book answers basic questions regarding quantifications and characterizations, distributions, modes of occurrence, physical and chemical properties, and more - in essence, all the information that is necessary to improve the models for precision prediction of the enigma of gas hydrates and other unconventionals. Blending geology, geophysics, geomechanics, petrophysics, and reservoir engineering, it explains in simple language the scientific concepts that are necessary to develop geological and reservoir models for unconventionals. Serving as a focal point for geoscientists and engineers conducting research that focuses on reservoir characteristics of unconventionals, Geological Controls for Gas Hydrate Formations and Unconventionals is a useful resource for a variety of other specialiststies including physicists, geochemists, exploration geologists, and petroleum and reservoir engineers. It details the key factors for successful exploration and development of unconventional reservoirs including discovery, data evaluation, full-field development, production, and abandonment, along with a vivid description ofn the worldwide occurrence of unconventional hydrocarbons.




Chemical and Biogeochemical Processes at Methane and Other Cold Seeps


Book Description

Methane is a strong climate-active gas, the concentration of which is rapidly increasing in the atmosphere. Vast methane reservoirs are hosted in seafloor sediments, both dissolved in pore fluids and trapped in gas hydrate. Cold seeps discharge significant amounts of this methane into the ocean. The rate of seabed methane discharge could be orders of magnitude higher than current estimates, creating considerable uncertainty. The extent of methane transfer from the seafloor to the water column and ultimately to the atmosphere is also uncertain. The seepage of methane and other hydrocarbons drives complex biogeochemical processes in marine sediments and the overlying water column. Seeps support chemosynthesis-based communities and impact the chemistry of the water column. Seeps may also play a critical role in ocean acidification and deoxygenation and can be geohazards, as well as a potential energy resource. Unraveling the complex and dynamic interactions and processes at marine seeps is crucial for our understanding of element cycling in the geo- and hydrosphere.




Gas Hydrates 2


Book Description

Gas hydrates in their natural environment and for potential industrial applications (Volume 2).




Methane Hydrates in Quaternary Climate Change


Book Description

Recent discoveries from ice-core and marine sediments suggest that global climate systems can change from glacial to near-interglacial temperatures within decades. In order to explain this phenomenon, the authors (all affiliated with the Department of Geological Sciences, U. of California) advance a hypothesis that suggests that the massive energy needed for these changes came for the release of "frozen" methane hydrates (clathrates) stored in marine sediments on continental margins. They argue that the release of the methane caused feedback processes that would explain the surprisingly rapid changes. Annotation copyrighted by Book News, Inc., Portland, OR.







World Atlas of Submarine Gas Hydrates in Continental Margins


Book Description

This world atlas presents a comprehensive overview of the gas-hydrate systems of our planet with contributions from esteemed international researchers from academia, governmental institutions and hydrocarbon industries. The book illustrates, describes and discusses gas hydrate systems, their geophysical evidence and their future prospects for climate change and continental margin geohazards from passive to active margins. This includes passive volcanic to non-volcanic margins including glaciated and non-glaciated margins from high to low latitudes. Shallow submarine gas hydrates allow a glimpse into the past from the Last Glacial Maximum (LGM) to modern environmental conditions to predict potential changes in future stability conditions while deep submarine gas hydrates remained more stable. This demonstrates their potential for rapid reactions for some gas hydrate provinces to a warming world, as well as helping to identify future prospects for environmental research. Three-dimensional and high-resolution seismic imaging technologies provide new insights into fluid flow systems in continental margins, enabling the identification of gas and gas escape routes to the seabed within gas hydrate environments, where seabed habitats may flourish. The volume contains a method section detailing the seismic imaging and logging while drilling techniques used to characterize gas hydrates and related dynamic processes in the sub seabed. This book is unique, as it goes well beyond the geophysical monograph series of natural gas hydrates and textbooks on marine geophysics. It also emphasizes the potential for gas hydrate research across a variety of disciplines. Observations of bottom simulating reflectors (BSRs) in 2D and 3D seismic reflection data combined with velocity analysis, electromagnetic investigations and gas-hydrate stability zone (GHSZ) modelling, provide the necessary insights for academic interests and hydrocarbon industries to understand the potential extent and volume of gas hydrates in a wide range of tectonic settings of continental margins. Gas hydrates control the largest and most dynamic reservoir of global carbon. Especially 4D, 3D seismic but also 2D seismic data provide compelling sub-seabed images of their dynamical behavior. Sub-seabed imaging techniques increase our understanding of the controlling mechanisms for the distribution and migration of gas before it enters the gas-hydrate stability zone. As methane hydrate stability depends mainly on pressure, temperature, gas composition and pore water chemistry, gas hydrates are usually found in ocean margin settings where water depth is more than 300 m and gas migrates upward from deeper geological formations. This highly dynamic environment may precondition the stability of continental slopes as evidenced by geohazards and gas expelled from the sea floor. This book provides new insights into variations in the character and existence of gas hydrates and BSRs in various geological environments, as well as their dynamics. The potentially dynamic behavior of this natural carbon system in a warming world, its current and future impacts on a variety of Earth environments can now be adequately evaluated by using the information provided in the world atlas. This book is relevant for students, researchers, governmental agencies and oil and gas professionals. Some familiarity with seismic data and some basic understanding of geology and tectonics are recommended.







Natural Gas Seepage


Book Description

The book offers a modern, comprehensive, and holistic view of natural gas seepage, defined as the visible or invisible flow of gaseous hydrocarbons from subsurface sources to Earth’s surface. Beginning with definitions, classifications for onshore and offshore seepage, and fundamentals on gas migration mechanisms, the book reports the latest findings for the global distribution of gas seepage and describes detection methods. Seepage implications are discussed in relation to petroleum exploration, environmental impacts (hazards, pollution, atmospheric emissions, and past climate change), emerging scientific issues (abiotic gas and methane on Mars), and the role of seeps in ancient cultures. With an updated bibliography and an integrated analysis of available data, the book offers a new fundamental awareness - gas seepage is more widespread than previously thought and influences all of Earth’s external “spheres”, including the hydrosphere, atmosphere, biosphere, and anthroposphere.