Elements of Petroleum Geology, Fourth Edition is a useful primer for geophysicists, geologists and petroleum engineers in the oil industry who wish to expand their knowledge beyond their specialized ...area. It is also an excellent introductory text for a university course in petroleum geoscience. This updated edition includes new case studies on non-conventional exploration, including tight oil and shale gas exploration, as well as coverage of the impacts on petroleum geology on the environment. Sections on shale reservoirs, flow units and containers, IOR and EOR, giant petroleum provinces, halo reservoirs, and resource estimation methods are also expanded.
UK shale gas: The story so far Selley, Richard C.
Marine and petroleum geology,
March 2012, 2012-3-00, Letnik:
31, Številka:
1
Journal Article
Recenzirano
The UK’s first well to encounter shale gas was drilled into the Upper Jurassic Kimmeridge Clay in 1875, but its significance was not realised at the time. 25 years ago research at Imperial College ...applied the US shale gas paradigm to evaluate the UK’s shale gas potential. Shale sequences with potential for gas production were identified in Carboniferous strata in the Midlands, and in Jurassic strata, particularly in the Weald. Without encouragement from Her Majesty’s Government no exploration resulted from this initial research. Publication of the results of the project was rejected by many UK journals. It was finally published in the USA in 1987. Subsequent evaluations of UK petroleum resources by the Department of Energy and its descendants published in 2001 and 2003 omitted any mention of shale gas resources. Recent timely re-evaluations of the UK’s shale gas potential have been carried out by the British Geological Survey and the Department for Energy & Climate Change. In 2008 the 13th Round of Onshore Licensing resulted in the award of several blocks for shale gas exploration, though bids were often based on a quest for both shale gas and conventional prospects. Cuadrilla Resource’s Preese Hall No. 1 well drilled in 2010 was the first well drilled to specifically test for UK shale gas. The same drilling and fracturing techniques that led to the shale gas renaissance in the USA are now being applied to extracting oil from organic-rich shales that are currently in the oil window. It is interesting to speculate that oil may be produced by such techniques from the thermally mature Jurassic shales in the Wessex and Weald basins in the southern UK.
► The UK’s first well to find shale gas was drilled in 1875. ► 25 years ago Imperial College evaluated the UK’s shale gas potential. ► Without encouragement from HMG no exploration resulted from this initial research. ► The BGS and DECC have recently re-evaluated UK shale gas resources. ► In 2010 the first well was drilled to specifically test for UK shale gas.
This Third Edition of Elements of Petroleum Geology is completely updated and revised to reflect the vast changes in the field since publication of the Second Edition. This book is a usefulprimer for ...geophysicists, geologists, and petroleum engineers in the oil industry who wish to expand their knowledge beyond their specialized area. It is also an excellent introductory text for a university course in petroleum geoscience.Elements of Petroleum Geology begins with an account of the physical and chemical properties of petroleum, reviewing methods of petroleum exploration and production. These methods include drilling, geophysical exploration techniques, wireline logging, and subsurface geological mapping. After describing the temperatures and pressures of the subsurface environment and the hydrodynamics of connate fluids, Selley examines the generation and migration of petroleum, reservoir rocks and trapping mechanisms, and the habit of petroleum in sedimentary basins. The book contains an account of the composition and formation of tar sands and oil shales, and concludes with a brief review of prospect risk analysis, reserve estimation, and other economic topics.
Updates the Second Edition completelyReviews the concepts and methodology of petroleum exploration and productionWritten by a preeminent petroleum geologist and sedimentologist with decades of petroleum exploration in remote corners of the worldContains information pertinent to geophysicists, geologists, and petroleum reservoir engineers New to this Edition: Updated statistics throughoutAdditional figures to illustrate key points and new developmentsNew information on drilling activity and production methods including crude oil, directional drilling, thermal techniques, and gas playsAdded coverage of 3D seismic interpretationNew section on pressure compartmentsNew section on hydrocarbon adsorption and absorption in source rocksCoverage of The Orinoco Heavy Oil Belt of VenezuelaUpdated chapter on unconventional petroleum
There are three types of rock-igneous, metamorphic and sedimentary. Sedimentary rocks form from the weathering, erosion, transportation and deposition of older rocks. Applied Sedimentology describes ...the formation, transportation and deposition of sediment, and the post-depositional processes that change soft sediment into sedimentary rock. Sedimentary rocks include sandstones, limestones and mudstones. All the world's coal, most of its water and fossil fuels, and many mineral deposits occur in sedimentary rocks. Applied Sedimentology shows how the study of sediments aids the exploration for and exploitation of natural resources, including water, ores and hydrocarbons.
* Completely revised edition; Like its precursor, it describes sediments from sand grains to sedimentary basins; Features up-to date account and critique of sequence and cyclostratigraphy * Extensively illustrated with photos and remotely sensed sea bed images describing sedimentary processes, products and depositional systems; Color plates illustrate sediment textures, lithologies, pore types, diagenetic textures, and carbonate and clastic sequence stratigraphic models* Emphasises the applications of sedimentology to the exploration for and exploitation of natural resources, including water, ores and hydrocarbons* Extensive references and up-to-date bibliography for further study
Any theory of petroleum generation must explain the following geological observations: most accumulations of hydrocarbons occur in sedimentary basins; in many cases, hydrocarbon accumulations are ...completely encased by impermeable sedimentary rocks, and commercial accumulations in the basement are always in lateral continuity with sedimentary rocks. Thus, the majority of commercial quantities of petroleum are formed by the thermal maturation of organic matter. The major groups of chemicals that occur in organic matter in plants and animals are proteins, carbohydrates, lipids, and lignins. These chemicals constitute organic matter, which is transformed into kerogen with burial diagenesis.
The amount of organic matter buried in the sediments is related to the ratio of organic productivity and destruction. The preservation of organic matter in seas and oceans is favored by anoxic bottom water conditions and rapid sedimentation rates. The four major anoxic environments favorable for the preservation of organic matter in sediments are stratified lakes, barred basins, continental shelves with upwelling, and ocean basin anoxic environments. Organic productivity and preservation in continental environments occur mainly in swamps.
Kerogen formation occurs in the shallow subsurface at near-normal temperatures and pressures. It involves the biogenic decay of organic matter. Methane, carbon dioxide, and water are given off by organic matter, leaving a complex hydrocarbon termed kerogen. This major phase in the evolution of organic matter in response to burial is called diagenesis. Three types of kerogen are identifiable: type I (algal), type II (liptinitic), and type III (humic). Type I tends to generate oil, type II generates oil and gas, and type III generates gas.
This stage is followed by the catagenesis stage, which occurs in the deeper subsurface as burial continues and pressures increase. Petroleum is released from kerogen during catagenesis. Oil generation occurs between 60 and 120 °C, and gas generation occurs between 120 and 225 °C. An empirical relationship between oil occurrence and clay dehydration suggests that the flushing of water from compacting clays plays an important role in primary migration.
The third stage, verging metamorphism, is called metagenesis and is a stage in which only methane is expelled.
Petroleum migration involves primary and secondary migration. Primary migration is the migration of hydrocarbons from the source rock (shales) into permeable carrier beds (sandstones and limestones). Secondary migration refers to the subsequent movement of oil and gas within permeable carrier beds and reservoirs. Primary migration theories are debated but include expulsion as protopetroleum, expulsion as petroleum in solution, expulsion as globules of oil in water, and expulsion as a continuous phase.
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