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Richard M. Pollastro

Publications and source records attributed to Richard M. Pollastro.

At least 19 recordsLinked to original sources

Considerations and applications of the illite/smectite geothermometer in hydrocarbon-bearing rocks of Miocene to Mississippian age

Empirical relationships between clay mineral transformations and temperature provide a basis for the use of clay minerals as geothermometers. Clay-mineral geothermometry has been applied mainly to diagenetic, hydrothermal, and contact- and burial-metamorphic settings to better understand the thermal histories of migrating fluids, hydrocarbon source beds, and ore and mineral formation. Quantitatively, the most important diagenetic clay mineral reaction in sedimentary rocks is the progressive transformation of smectite to illite via mixed-layer illite/smectite (I/S). Changes in both the illite/smectite ratio and ordering of I/S, as determined from X-ray powder diffraction profiles, correlate with changes in temperature due to burial depth. Although the smectite-to-illite reaction may be influenced by several factors, reaction progress appears to be strongly controlled by temperature. Studies show that the model proposed by Hoffman and Hower in 1979 is applicable in burial diagenetic settings from about 5 to 330 Ma, and includes most rocks about Miocene to Mississippian in age. Reliability of the I/S geothermometer is, however, dependent upon a good understanding of the rock's original clay-mineral composition. Changes in the ordering of I/S are particularly useful in the exploration for hydrocarbons because of the common coincidence between the temperatures for the conversion from random-to-ordered I/S and those for the onset of peak, or main phase, oil generation. Here, the utility of the I/S geothermometer is reviewed in hydrocarbon-bearing rocks of Miocene to Mississippian age. Using three common applications, the I/S geothermometer is compared to other mineral geothermometers, organic maturation indices, and grades of indigenous hydrocarbons. Good agreement between changes in ordering of I/S and calculated maximum burial temperatures or hydrocarbon maturity suggests that I/S is a reliable semiquantitative geothermometer and an excellent measures of thermal maturity.

Clays and Clay Minerals

Geologic assessment of undiscovered oil and gas resources of the U.S. portion of the Michigan Basin

In 2004, the U.S. Geological Survey (USGS) completed an assessment of the undiscovered oil and gas potential of the U.S. portion of the Michigan Basin. For this assessment, the Michigan Basin includes most of the State of Michigan, as well as parts of Illinois, Indiana, Minnesota, Ohio, and Wisconsin. The assessment was based on the geologic elements of each of the six total petroleum systems defined in the basin, including (1) hydrocarbon source rocks (source-rock maturation and hydrocarbon generation and migration), (2) reservoir rocks (sequence stratigraphy and petrophysical properties), and (3) hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS estimated mean technically recoverable undiscovered continuous and conventional resources that total 990 million barrels of oil, 11.4 trillion cubic feet of natural gas, and 219 million barrels of natural gas liquids. Digital Data Series 69-T (DDS-69-T) is cataloged in the Pubs Warehouse as Data Series 69-T (DS-69-T).

Illinois, Indiana, Michigan, Minnesota, Ohio, Wisc

National Assessment of Oil and Gas Project: geologic assessment of undiscovered gas hydrate resources on the North Slope, Alaska

Scientists with the U.S. Geological Survey have completed the first assessment of the undiscovered, technically recoverable gas hydrate resources beneath the North Slope of Alaska. This assessment indicates the existence of technically recoverable gas hydrate resources—that is, resources that can be discovered, developed, and produced using current technology. The approach used in this assessment followed standard geology-based USGS methodologies developed to assess conventional oil and gas resources. In order to use the USGS conventional assessment approach on gas hydrate resources, three-dimensional industry-acquired seismic data were analyzed. The analyses indicated that the gas hydrates on the North Slope occupy limited, discrete volumes of rock bounded by faults and downdip water contacts. This assessment approach also assumes that the resource can be produced by existing conventional technology, on the basis of limited field testing and numerical production models of gas hydrate-bearing reservoirs. The area assessed in northern Alaska extends from the National Petroleum Reserve in Alaska on the west through the Arctic National Wildlife Refuge on the east and from the Brooks Range northward to the State-Federal offshore boundary (located 3 miles north of the coastline). This area consists mostly of Federal, State, and Native lands covering 55,894 square miles. Using the standard geology-based assessment methodology, the USGS estimated that the total undiscovered technically recoverable natural-gas resources in gas hydrates in northern Alaska range between 25.2 and 157.8 trillion cubic feet, representing 95 percent and 5 percent probabilities of greater than these amounts, respectively, with a mean estimate of 85.4 trillion cubic feet.

Alaska

Assessment of undiscovered oil and gas resources of the Cretaceous-Tertiary Composite Total Petroleum System, Taranaki Basin Assessment Unit, New Zealand

The Cretaceous-Tertiary Composite Total Petroleum System coincident Taranaki Basin Assessment Unit was recently assessed for undiscovered technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey (USGS) World Energy Resources Project, World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 487 million barrels of oil, 9.8 trillion cubic feet of gas, and 408 million barrels of natural gas liquids.

Taranaki Basin

Assessment of undiscovered conventional oil and gas resources of the Arabian Peninsula and Zagros Fold Belt, 2012

Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 86 billion barrels of oil and 336 trillion cubic feet of undiscovered natural gas resources in the Arabian Peninsula and Zagros Fold Belt. The USGS assessed the potential for undiscovered conventional oil and gas accumulations within the Arabian Peninsula and Zagros Fold Belt as part of the USGS World Petroleum Resources Project. Twenty-three assessment units within seven petroleum systems were quantitatively assessed in this study, which represents a reassessment of this area last published in 2000.

Fact Sheet

Assessment of undiscovered oil and gas resources of the Amu Darya Basin and Afghan-Tajik Basin Provinces, Afghanistan, Iran, Tajikistan, Turkmenistan, and Uzbekistan, 2011

Using a geology-based assessment methodology, the U.S. Geological Survey estimated volumes of undiscovered, technically recoverable, conventional petroleum resources for the Amu Darya Basin and Afghan–Tajik Basin Provinces of Afghanistan, Iran, Tajikistan, Turkmenistan, and Uzbekistan. The mean volumes were estimated at 962 million barrels of crude oil, 52 trillion cubic feet of natural gas, and 582 million barrels of natural gas liquids for the Amu Darya Basin Province and at 946 million barrels of crude oil, 7 trillion cubic feet of natural gas, and 85 million barrels of natural gas liquids for the Afghan–Tajik Basin Province.

Amu Darya Basin;Afghan-tajik Basin Provinces

Assessment of undiscovered oil and gas resources of the southern Siberian craton (Baykit High, Nepa--Botuoba High, Angara--Lena Terrace, and Cis--Patom Foredeep Provinces), Russia, 2011

Using a geology-based assessment methodology, the U.S. Geological Survey estimated volumes of undiscovered, technically recoverable, conventional petroleum resources for the southern Siberian craton provinces of Russia. The mean volumes were estimated at 3.0 billion barrels of crude oil, 63.3 trillion cubic feet of natural gas, and 1.2 billion barrels of natural gas liquids.

Fact Sheet

Assessment of undiscovered oil and gas resources in conventional and continuous petroleum systems in the Upper Cretaceous Eagle Ford Group, U.S. Gulf Coast region, 2011

Using a geology-based assessment methodology, the U.S. Geological Survey assessed means of (1) 141 million barrels of oil (MMBO), 502 billion cubic feet of natural gas (BCFG), and 16 million barrels of natural gas liquids (MMBNGL) in the conventional Eagle Ford Updip Sandstone Oil and Gas Assessment Unit (AU); (2) 853 MMBO, 1,707 BCFG, and 34 MMBNGL in the continuous Eagle Ford Shale Oil AU; and (3) 50,219 BCFG and 2,009 MMBNGL in the continuous Eagle Ford Shale Gas AU in onshore lands and State waters of the Gulf Coast.

Gulf Coast Region

Assessment of undiscovered conventional oil and gas resources of Bonaparte Basin, Browse Basin, Northwest Shelf, and Gippsland Basin Provinces, Australia, 2011

Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 4.7 billion barrels of undiscovered oil and 227 trillion cubic feet of undiscovered natural gas in three major offshore petroleum basins of northwest Australia and in the Gippsland Basin of southeast Australia.

Bonaparte Basin;Browse Basin;Northwest Shelf;Gipps

Assessment of undiscovered oil and gas resources of the South Africa Coastal Province, Africa

The South Africa Coastal Province along the South Africa coast recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 2.13 billion barrels of oil, 35.96 trillion cubic feet of natural gas, and 1,115 million barrels of natural gas liquids.

Fact Sheet

Assessment of undiscovered oil and gas resources of four East Africa Geologic Provinces

Four geologic provinces along the east coast of Africa recently were assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 27.6 billion barrels of oil, 441.1 trillion cubic feet of natural gas, and 13.77 billion barrels of natural gas liquids.

Fact Sheet

Assessment of undiscovered oil and gas resources of the Assam, Bombay, Cauvery, and Krishna-Godavari Provinces, South Asia, 2011

Using a geology-based assessment methodology, the U.S. Geological Survey estimated volumes of undiscovered, technically recoverable, conventional petroleum resources for the Assam, Bombay, Cauvery, and Krishna–Godavari Provinces, South Asia. The estimated mean volumes are as follows: (1) Assam Province, 273 million barrels of crude oil, 1,559 billion cubic feet of natural gas, and 43 million barrels of natural gas liquids; (2) Bombay Province, 1,854 million barrels of crude oil, 15,417 billion cubic feet of natural gas, and 498 million barrels of natural gas liquids; (3) Cauvery Province, 941 million barrels of crude oil, 25,208 billion cubic feet of natural gas, and 654 million barrels of natural gas liquids; and (4) Krishna–Godavari Province, 466 million barrels of crude oil, 37,168 billion cubic feet of natural gas, and 484 million barrels of natural gas liquids. The totals for the four provinces are 3,534 million barrels of crude oil, 79,352 billion cubic feet of natural gas, and 1,679 million barrels of natural gas liquids.

Assam Province;Bombay Province;Cauvery Province;Kr

Assessment of undiscovered oil and gas resources of the East Coast Mesozoic basins of the Piedmont, Blue Ridge Thrust Belt, Atlantic Coastal Plain, and New England Provinces, 2011

During the early opening of the Atlantic Ocean in the Mesozoic Era, numerous extensional basins formed along the eastern margin of the North American continent from Florida northward to New England and parts of adjacent Canada. The basins extend generally from the offshore Atlantic continental margin westward beneath the Atlantic Coastal Plain to the Appalachian Mountains. Using a geology-based assessment method, the U.S. Geological Survey estimated a mean undiscovered natural gas resource of 3,860 billion cubic feet and a mean undiscovered natural gas liquids resource of 135 million barrels in continuous accumulations within five of the East Coast Mesozoic basins: the Deep River, Dan River-Danville, and Richmond basins, which are within the Piedmont Province of North Carolina and Virginia; the Taylorsville basin, which is almost entirely within the Atlantic Coastal Plain Province of Virginia and Maryland; and the southern part of the Newark basin (herein referred to as the South Newark basin), which is within the Blue Ridge Thrust Belt Province of New Jersey. The provinces, which contain these extensional basins, extend across parts of Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, and Massachusetts.

East Coast Mesozoic Basins