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James L. Coleman

Publications and source records attributed to James L. Coleman.

26 records · Page 2Linked to original sources

Assessment of undiscovered oil and gas resources of the Devonian Marcellus Shale of the Appalachian Basin Province

Using a geology-based assessment methodology, the U.S. Geological Survey (USGS) estimated a mean undiscovered natural gas resource of 84,198 billion cubic feet and a mean undiscovered natural gas liquids resource of 3,379 million barrels in the Devonian Marcellus Shale within the Appalachian Basin Province. All this resource occurs in continuous accumulations. In 2011, the USGS completed an assessment of the undiscovered oil and gas potential of the Devonian Marcellus Shale within the Appalachian Basin Province of the eastern United States. The Appalachian Basin Province includes parts of Alabama, Georgia, Kentucky, Maryland, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia. The assessment of the Marcellus Shale is based on the geologic elements of this formation's total petroleum system (TPS) as recognized in the characteristics of the TPS as a petroleum source rock (source rock richness, thermal maturation, petroleum generation, and migration) as well as a reservoir rock (stratigraphic position and content and petrophysical properties). Together, these components confirm the Marcellus Shale as a continuous petroleum accumulation. Using the geologic framework, the USGS defined one TPS and three assessment units (AUs) within this TPS and quantitatively estimated the undiscovered oil and gas resources within the three AUs. For the purposes of this assessment, the Marcellus Shale is considered to be that Middle Devonian interval that consists primarily of shale and lesser amounts of bentonite, limestone, and siltstone occurring between the underlying Middle Devonian Onondaga Limestone (or its stratigraphic equivalents, the Needmore Shale and Huntersville Chert) and the overlying Middle Devonian Mahantango Formation (or its stratigraphic equivalents, the upper Millboro Shale and middle Hamilton Group).

Alabama, Georgia, Kentucky, Maryland, New York, Oh↗

A methodology for the assessment of unconventional (continuous) resources with an application to the Greater Natural Buttes gas field, Utah

The Greater Natural Buttes tight natural gas field is an unconventional (continuous) accumulation in the Uinta Basin, Utah, that began production in the early 1950s from the Upper Cretaceous Mesaverde Group. Three years later, production was extended to the Eocene Wasatch Formation. With the exclusion of 1100 non-productive (“dry”) wells, we estimate that the final recovery from the 2500 producing wells existing in 2007 will be about 1.7 trillion standard cubic feet (TSCF) (48.2 billion cubic meters (BCM)). The use of estimated ultimate recovery (EUR) per well is common in assessments of unconventional resources, and it is one of the main sources of information to forecast undiscovered resources. Each calculated recovery value has an associated drainage area that generally varies from well to well and that can be mathematically subdivided into elemental subareas of constant size and shape called cells. Recovery per 5-acre cells at Greater Natural Buttes shows spatial correlation; hence, statistical approaches that ignore this correlation when inferring EUR values for untested cells do not take full advantage of all the information contained in the data. More critically, resulting models do not match the style of spatial EUR fluctuations observed in nature. This study takes a new approach by applying spatial statistics to model geographical variation of cell EUR taking into account spatial correlation and the influence of fractures. We applied sequential indicator simulation to model non-productive cells, while spatial mapping of cell EUR was obtained by applying sequential Gaussian simulation to provide multiple versions of reality (realizations) having equal chances of being the correct model. For each realization, summation of EUR in cells not drained by the existing wells allowed preparation of a stochastic prediction of undiscovered resources, which range between 2.6 and 3.4 TSCF (73.6 and 96.3 BCM) with a mean of 2.9 TSCF (82.1 BCM) for Greater Natural Buttes. A second approach illustrates the application of multiple-point simulation to assess a hypothetical frontier area for which there is no production information but which is regarded as being similar to Greater Natural Buttes.

Utah↗

Assessment of undiscovered natural gas resources of the Arkoma Basin province and geologically related areas

Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean volumes of 38 trillion cubic feet (TCF) of undiscovered natural gas, 159 million barrels of natural gas liquid (MMBNGL), and no oil in accumulations of 0.5 million barrels (MMBO) or larger in the Arkoma Basin Province and related areas. More than 97 percent of the undiscovered gas occurs in continuous accumulations-70 percent in shale gas formations, 18 percent in a basin-centered accumulation with tight sandstone reservoirs, and 9 percent in coal beds. Less than 3 percent of the natural gas occurs in conventional accumulations.

Fact Sheet↗

Geology and assessment of undiscovered oil and gas resources in Mesozoic (Jurassic and Cretaceous) rocks of the onshore and state waters of the Gulf of Mexico Region, U.S.A

The U.S. Geological Survey (USGS) is in the final phase of the most recent assessment of the undiscovered technically recoverable oil and gas resources of the U.S. Gulf of Mexico coastal plain and state waters. Ongoing geologic, geochemical, and petrophysical framework studies have defined the total petroleum systems and assessment units (AUs) in the Gulf Coast region. Current studies examine the Mesozoic (Jurassic and Cretaceous) source rocks and reservoir units, and recent studies have assessed the undiscovered resources in Tertiary and certain Jurassic and Cretaceous units. The Upper Jurassic and Lower Cretaceous Cotton Valley Group and Lower Cretaceous Hosston and Travis Peak formations, as well as the Upper Cretaceous Taylor and Navarro groups and the Tuscaloosa and Woodbine groups downdip shelf-margin deltas, were assessed in 2006. Tertiary strata were assessed in 2007. Jurassic strata presently under evaluation include the Upper Jurassic Norphlet, Smackover, Haynesville, and Bossier formations. Lower Cretaceous units to be assessed in the present study include the Knowles Limestone, Sligo Formation, Trinity Group, Fredericksburg Group, and lower part of the Washita Group. Upper Cretaceous rocks being assessed include the Buda Limestone of the Washita Group, Eagle Ford Group (Eagle Ford shale, and the updip Tuscaloosa and Woodbine groups), Austin Chalk (Group), and Tokio and Eutaw formations. For each AU, a geologic model is developed to define hydrocarbon source, charge, migration, trap, and reservoir, and to estimate technically recoverable undiscovered oil and gas resources. The USGS assessment is focused on evaluating conventional clastic and carbonate deposystems, as well as resource volumes in emerging unconventional gas, shale gas, and shale oil plays currently attracting global attention.

Texas, Louisiana, Alabama, Mississippi, Florida↗

USGS assessment of undiscovered oil and gas resources in Paleogene strata of the U.S. Gulf of Mexico coastal plain and state waters

This report presents a review of the U.S. Geological Survey ( USGS ) 2007 assessment of the undiscovered oil and gas resources in Paleogene strata underlying the U.S. Gulf of Mexico Coastal Plain and state waters. Geochemical, geologic, geophysical, thermal maturation, burial history, and paleontologic studies have been combined with regional cross sections and data from previous USGS petroleum assessments have helped to define the major petroleum systems and assessment units. Accumulations of both conventional oil and gas and continuous coal-bed gas within these petroleum systems have been digitally mapped and evaluated, and undiscovered resources have been assessed following USGS methodology. The primary source intervals for oil and gas in Paleogene (and Cenozoic) reservoirs are coal and shale rich in organic matter within the Wilcox Group (Paleocene-Eocene) and Sparta Formation of the Claiborne Group (Eocene); in addition, Cretaceous and Jurassic source rocks probably have contributed substantial petroleum to Paleogene (and Cenozoic) reservoirs. For the purposes of the assessment, Paleogene strata have divided into the following four stratigraphic study intervals: (1) Wilcox Group (including the Midway Group and the basal Carrizo Sand of the Claiborne Group; Paleocene-Eocene); (2) Claiborne Group (Eocene); (3) Jackson and Vicksburg Groups (Eocene-Oligocene); and (4) the Frio-Anahuac Formations (Oligocene). Recent discoveries of coal-bed gas in Paleocene strata confirm a new petroleum system that was not recognized in previous USGS assessments. In total, 26 conventional Paleogene assessment units are defined. In addition, four Cretaceous-Paleogene continuous (coal-bed gas) assessment units are included in this report. Initial results of the assessment will be released as USGS Fact Sheets (not available at the time of this writing). Comprehensive reports for each assessment unit are planned to be released via the internet and distributed on CD-ROMs within the next year.

U.S. Gulf Coast↗

Undiscovered oil and gas resources underlying the U.S. portions of the Great Lakes, 2005

The U.S. Geological Survey (USGS) completed an assessment of the undiscovered oil and gas potential of the U.S. portions of the Appalachian Basin and the Michigan Basin in 2002 and 2004, respectively. Following the assessments of these two basins, oil and gas allocations were assigned to the U.S. portions of the Great Lakes - Lake Superior (Michigan, Minnesota, and Wisconsin), Lake Michigan (Illinois, Indiana, Michigan, and Wisconsin), Lake Huron (Michigan), Lake Erie (Michigan, New York, Ohio, and Pennsylvania), and Lake Ontario (New York). Allocations for Lake St. Clair (Michigan) were included with those of Lake Erie. The allocations are based on the geologic elements of each total petroleum system defined in the region and the projected extent of those elements from onshore beneath each of the lakes. These geologic elements include the hydrocarbon source rocks, reservoir rocks, and traps. By using this geologic framework, the USGS defined 8 total petroleum systems and 21 assessment units within the Great Lakes and estimated the quantity of undiscovered technically recoverable oil and gas resources within 16 of the 21 assessment units in the Great Lakes.

Fact Sheet↗