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Ronald R. Charpentier

Publications and source records attributed to Ronald R. Charpentier.

At least 109 records · Page 6Linked to original sources
USGS2007

Executive Summary — Assessment of undiscovered oil and gas resources of the San Joaquin Basin Province of California, 2003

In 2003, the U.S. Geological Survey (USGS) completed an assessment of the oil and gas resource potential of the San Joaquin Basin Province of California (fig. 1.1). The assessment is based on the geologic elements of each Total Petroleum System defined in the province, including hydrocarbon source rocks (source-rock type and maturation and hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined five total petroleum systems and ten assessment units within these systems. Undiscovered oil and gas resources were quantitatively estimated for the ten assessment units (table 1.1). In addition, the potential was estimated for further growth of reserves in existing oil fields of the San Joaquin Basin.

California↗
USGS2007

Assessment of Undiscovered Natural Gas Resources of the Sacramento Basin Province of California, 2006

The U.S. Geological Survey (USGS) recently completed a new assessment of undiscovered natural gas resources of the Sacramento Basin Province of California. Using a geology-based assessment methodology, the USGS mean estimates of undiscovered, technically recoverable resources are 534 billion cubic feet of natural gas and 323 thousand barrels of natural gas liquids in the Sacramento Basin Province. Additional undiscovered oil accumulations larger than 0.5 million barrels are considered unlikely.

Fact Sheet↗
USGS2007

A Program for Partitioning Shifted Truncated Lognormal Distributions into Size-Class Bins

In recent years, oil and gas accumulation-size frequency distributions have become a standard way to characterize undiscovered conventional oil and gas resources that have been postulated by geologic assessments. The preparation of such distributions requires the assessment geologists to explicitly choose parameters for the probability distribution for the sizes of undiscovered accumulations. The purpose of this report is to present a computational scheme for obtaining a binned size frequency distribution of undiscovered accumulations when the undiscovered accumulation size distribution is shifted truncated lognormal.

Open-File Report↗
USGS2007

U.S. Geological Survey input-data form and operational procedure for the assessment of conventional petroleum accumulations: Chapter 25 in Petroleum systems and geologic assessment of oil and gas in the San Joaquin Basin Province, California

The U.S. Geological Survey model for undiscovered conventional accumulations is designed to aid in the assessment of crude oil, natural gas, and natural gas liquids (collectively called petroleum) resources. Conventional accumulations may be described in terms of discrete fields or pools localized in structural and stratigraphic traps by the buoyancy of oil or natural gas in water. Conventional accumulations are commonly bounded by a down-dip water contact. The assessment model requires estimates of the number and sizes of undiscovered conventional accumulations. Technically recoverable petroleum resources from undiscovered conventional accumulations are calculated by statistically combining probability distributions of the estimated number and sizes of undiscovered accumulations, along with associated risks and coproduct ratios. Probabilistic estimates of petroleum resources are given for oil in oil accumulations, gas (associated/dissolved) in oil accumulations, natural gas liquids in oil accumulations, gas (nonassociated) in gas accumulations, and total liquids (oil and natural gas liquids) in gas accumulations.

Professional Paper↗
USGS2007

A Monte Carlo simulation method for the assessment of undiscovered, conventional oil and gas: Chapter 26 in Petroleum systems and geologic assessment of oil and gas in the San Joaquin Basin Province, California

The U.S. Geological Survey has developed two Monte Carlo programs for assessment of undiscovered conventional oil and gas resources. EMCEE (for Energy Monte Carlo) and Emc2 (for Energy Monte Carlo program 2) are programs that calculate probabilistic estimates of undiscovered resources based on input distributions for numbers and sizes of undiscovered fields. Emc2 uses specific types of distributions for the input, whereas EMCEE allows greater flexibility of the input distribution types.

Professional Paper↗
USGS2006

Geology and total petroleum systems of the West-Central Coastal province (7203), West Africa

The West-Central Coastal Province of the Sub-Saharan Africa Region consists of the coastal and offshore areas of Cameroon, Equatorial Guinea, Gabon, Democratic Republic of the Congo, Republic of the Congo, Angola (including the disputed Cabinda Province), and Namibia. The area stretches from the east edge of the Niger Delta south to the Walvis Ridge. The West-Central Coastal Province includes the Douala, Kribi-Campo, Rio Muni, Gabon, Congo, Kwanza, Benguela, and Namibe Basins, which together form the Aptian salt basin of equatorial west Africa. The area has had significant exploration for petroleum; more than 295 oil fields have been discovered since 1954. Since 1995, several giant oil fields have been discovered, especially in the deep-water area of the Congo Basin. Although many total petroleum systems may exist in the West-Central Coastal Province, only four major total petroleum systems have been defined. The area of the province north of the Congo Basin contains two total petroleum systems: the Melania-Gamba Total Petroleum System, consisting of Lower Cretaceous source and reservoir rocks, and the Azile-Senonian Total Petroleum System, consisting of Albian to Turonian source rocks and Cretaceous reservoir rocks. Two assessment units are defined in the West-Central Coastal Province north of the Congo Basin: the Gabon Subsalt and the Gabon Suprasalt Assessment Units. The Congo Basin contains the Congo Delta Composite Total Petroleum System, consisting of Lower Cretaceous to Tertiary source and reservoir rocks. The Central Congo Delta and Carbonate Platform and the Central Congo Turbidites Assessment Units are defined in the Congo Delta Composite Total Petroleum System. The area south of the Congo Basin contains the Cuanza Composite Total Petroleum System, consisting of Lower Cretaceous to Tertiary source and reservoir rocks. The Cuanza-Namibe Assessment Unit is defined in the Cuanza Composite Total Petroleum System. The U.S. Geological Survey (USGS) assessed the potential for undiscovered conventional oil and gas resources in this province as part of its World Petroleum Assessment 2000. The USGS estimated a mean of 29.7 billion barrels of undiscovered conventional oil, 88.0 trillion cubic feet of gas, and 4.2 billion barrels of natural gas liquids. Most of the hydrocarbon potential remains in the offshore waters of the province in the Central Congo Turbidites Assessment Unit. Large areas of the offshore parts of the Kwanza, Douala, Kribi-Campo, and Rio Muni Basins are underexplored, considering their size, and current exploration activity suggests that the basins have hydrocarbon potential. Since about 1995, the offshore part of the Congo Basin has become a major area for new field discoveries and for hydrocarbon exploration, and many deeper water areas in the basin have excellent hydrocarbon potential. Gas resources may be significant and accessible in areas where the zone of oil generation is relatively shallow.

Bulletin↗
USGS2006

Geology and total petroleum systems of the Gulf of Guinea province of West Africa

The U.S. Geological Survey (USGS) assessed the potential for undiscovered conventional oil and gas resources in the Gulf of Guinea Province, west-central Africa, as part of its World Petroleum Assessment 2000. The USGS estimated a mean of 1,004 million barrels of conventional undiscovered oil, 10,071 billion cubic feet of gas, and 282 million barrels of natural gas liquids. Most of the hydrocarbon potential is postulated to be in the offshore, deeper waters of the province.

Bulletin↗
USGS2006

Assessment of undiscovered oil and gas resources of the Mackenzie Delta province, North America, 2004

Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 40 trillion cubic feet of undiscovered nonassociated gas, a mean of 10.5 billion barrels of undiscovered oil (with 46.6 trillion cubic feet of associated gas), and a mean of 4.0 billion barrels of undiscovered natural gas liquids in the Mackenzie Delta Province of North America, exclusive of the unassessed deep-water portion of the province.

Fact Sheet↗
USGS2006

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↗
USGS2006

Assessment of Undiscovered Gas Resources of the Eastern Oregon and Washington Province, 2006

Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 2.4 trillion cubic feet (TCF) of undiscovered natural gas in the Eastern Oregon and Washington Province. More than 90 percent, or 2.1 TCF, of the estimated undiscovered natural gas is continuous gas estimated to be trapped in Tertiary rocks overlain by the Columbia River Basalt Group.

Fact Sheet↗
USGS2006

Assessment of coalbed gas resources in Cretaceous and Tertiary rocks on the North Slope, Alaska, 2006

The North Slope of Alaska is a vast area of land north of the Brooks Range, extending from the Chukchi Sea eastward to the Canadian border. This Arctic region is known to contain extensive coal deposits; hypothetical coal resource estimates indicate that nearly 4 trillion short tons of coal are in Cretaceous and Tertiary rocks. Because of the large volume of coal, other studies have indicated that this region might also have potential for significant coalbed gas resources. The present study represents the first detailed assessment of undiscovered coalbed gas resources beneath the North Slope by the USGS. The assessment is based on the total petroleum system (TPS) concept. Geologic elements within a TPS relate to hydrocarbon source rocks (maturity, hydrocarbon generation, migration), the characteristics of reservoir rocks, and trap and seal formation. In the case of coalbed gas, the coal beds serve as both source rock and reservoir. The Brookian Coalbed Gas Composite TPS includes coal-bearing rocks in Cretaceous and Tertiary strata underlying the North Slope and adjacent Alaska State waters. Assessment units (AUs) within the TPS (from oldest to youngest) include the Nanushuk Formation Coalbed Gas AU, the Prince Creek and Tuluvak Formations Coalbed Gas AU, and the Sagavanirktok Formation Coalbed Gas AU.

Alaska↗
USGS2006

An allocation of undiscovered oil and gas resources to Big South Fork National Recreation Area and Obed Wild and Scenic River, Kentucky and Tennessee

The U.S. Geological Survey (USGS) estimated volumes of undiscovered oil and gas resources that may underlie Big South Fork National Recreation Area and Obed Wild and Scenic River in Kentucky and Tennessee. Applying the results of existing assessments of undiscovered resources from three assessment units in the Appalachian Basin Province and three plays in the Cincinnati Arch Province that include these land parcels, the USGS allocated approximately (1) 16 billion cubic feet of gas, 15 thousand barrels of oil, and 232 thousand barrels of natural gas liquids to Big South Fork National Recreation Area; and (2) 0.5 billion cubic feet of gas, 0.6 thousand barrels of oil, and 10 thousand barrels of natural gas liquids to Obed Wild and Scenic River. These estimated volumes of undiscovered resources represent potential volumes in new undiscovered fields, but do not include potential additions to reserves within existing fields.

Open-File Report↗
USGS2005

Guiding principles of USGS methodology for assessment of undiscovered conventional oil and gas resources

During the last 30 years, the methodology for assessment of undiscovered conventional oil and gas resources used by the Geological Survey has undergone considerable change. This evolution has been based on five major principles. First, the U.S. Geological Survey has responsibility for a wide range of U.S. and world assessments and requires a robust methodology suitable for immaturely explored as well as maturely explored areas. Second, the assessments should be based on as comprehensive a set of geological and exploration history data as possible. Third, the perils of methods that solely use statistical methods without geological analysis are recognized. Fourth, the methodology and course of the assessment should be documented as transparently as possible, within the limits imposed by the inevitable use of subjective judgement. Fifth, the multiple uses of the assessments require a continuing effort to provide the documentation in such ways as to increase utility to the many types of users. Undiscovered conventional oil and gas resources are those recoverable volumes in undiscovered, discrete, conventional structural or stratigraphic traps. The USGS 2000 methodology for these resources is based on a framework of assessing numbers and sizes of undiscovered oil and gas accumulations and the associated risks. The input is standardized on a form termed the Seventh Approximation Data Form for Conventional Assessment Units. Volumes of resource are then calculated using a Monte Carlo program named Emc2, but an alternative analytic (non-Monte Carlo) program named ASSESS also can be used. The resource assessment methodology continues to change. Accumulation-size distributions are being examined to determine how sensitive the results are to size-distribution assumptions. The resource assessment output is changing to provide better applicability for economic analysis. The separate methodology for assessing continuous (unconventional) resources also has been evolving. Further studies of the relationship between geologic models of conventional and continuous resources will likely impact the respective resource assessment methodologies. ?? 2005 International Association for Mathematical Geology.

Conference Paper↗