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G.L. Dolton

Publications and source records attributed to G.L. Dolton.

At least 19 recordsLinked to original sources
USGS1995

Annotated bibliography of methodology for assessment of undiscovered oil and gas resources

An annotated bibliography of methodology of assessment of undiscovered oil and gas resources is presented as a useful reference for those engaged in resource assessment. The articles that are included deal only with quantitative assessment of undiscovered or inferred resources. the articles in this bibliography are classified largely according to the major assessment method that was applied in each situation. Major assessment methods include areal and volumetric yield methods, field size distributions, historical extrapolation, deposit modeling, organic geochemical mass balance methods, and direct expert assessment. Other categories include mathematical tools, reserve growth/confirmation, quantitative characterization of undiscovered resources, and general topics. For the purpose of future updates, we solicit contributions of articles that may have been missed in the preparation of this bibliography. ?? 1995 Oxford University Press.

Nonrenewable Resources↗
USGS1995

1995 National assessment of United States oil and gas resources; results, methodology, and supporting data

This report summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States by the U.S. Geological Survey. A parallel study of the Federal offshore is being conducted by the Minerals Management Service. Estimates are made of technically recoverable oil, including measured (proved) reserves, future additions to reserves in existing fields, and undiscovered resources. Estimates are also made of the technically recoverable conventional resources of natural gas in measured reserves, in anticipated growth of reserves in existing fields, and in undiscovered resources. Additionally, an assessment is made of recoverable resources in continuous-type (largely unconventional) accumulations in sandstones, shales, chalks, and coal beds.

Data Series↗
USGS1993

Undiscovered oil and gas resources and leasing status of forestlands in Wyoming

All of four national forests, one national grassland, and parts of four additional forests lie within the State of Wyoming. Some of these National Forest System lands have moderate to high potential for undiscovered oil and gas resources. In the 1989 National Assessment of undiscovered oil and gas and in various Open-File Reports, the U.S. Geological Survey described oil and gas plays and presented estimates of recoverable conventional oil and gas resources for these plays. Estimated resources in plays affecting NFS lands in Wyoming are substantial. Of special significance are undiscovered recoverable conventional resources (mean estimate) of approximately 1,010 million barrels of oil, 10,611 billion cubic feet of gas, and 188 million barrels of natural gas liquids assessed in ten plays that include National Forest System lands in the Thunder Basin National Grassland and the Bridger-Teton, Targhee, Caribou, and Shoshone National Forests in Wyoming. Approximately 5,715,570 acres in the forests and grassland are available for leasing or are expected to be available for leasing by mid-1993. Poor accessibility, environmental concerns, and geologic factors such as complex structure and greater drilling depths to potential reservoirs may cause higher exploration risks and operating costs on NFS lands. However, cooperative arrangements with the U.S. Forest Service, in addition to carefully planned exploration and development programs, can facilitate operations in remote and environmentally sensitive areas, and could result in opening new exploration frontiers in Wyoming.

Book chapter↗
USGS1989

Estimates of undiscovered conventional oil and gas resources in the United States: A part of the Nation's energy endowment

In 1987, the U.S. Geological Survey and the Minerals Management Service completed a new assessment of the undiscovered conventional resources of crude oil and natural gas in the United States. This assessment responded to a national need for such estimates, considered new geological, technologic, and economic information, and used more definitive methods of resource appraisal than previous assessments. The conventional resources assessed were (1) those considered recoverable under current technology and (2) those that could be developed and produced economically under specified price and cost relationships, excluding exploration costs. This study did not include resources from tar deposits, intractable heavy oil deposits, oil shales, gas in low-permeability (less than 0.1 millidarcy in situ) "tight" reservoirs, coal bed methane, gas in geopressured shales and brines, and natural gas hydrates (clathrates). For this study, the United States was divided into 13 regions (9 onshore and 4 offshore), including the Exclusive Economic Zone (EEZ). The 13 regions were further divided into 115 provinces (appendix A, figs. Al and A2). The resource estimates were based fundamentally upon review and analysis of petroleum geology and the exploration history of oil and gas plays in these provinces. Probability procedures were used in their derivation. Because of the uncertainty in estimating undiscovered resources, the estimated quantities are reported as a range of values that correspond to different probability levels. The undiscovered recoverable conventional resources of oil for the United States, as of January, 1, 1987, are estimated to range from 33 to 70 billion barrels, with a mean estimate of 49 billion barrels: the estimates of gas range from 307 to 507 trillion cubic feet, with a mean estimate of 399 trillion cubic feet (table 1). Range estimates correspond to 95-percent probability (19 in 20 chance) and 5-percent probability (1 in 20 chance) of there being more than those amounts, respectively. Corresponding estimates for natural gas liquids (NGL) range from 6 to 12 billion barrels, with a mean estimate of 9 billion barrels. Further, the assessed undiscovered economically recoverable oil and gas resources for the United States, as of January 1, 1987, are estimated to range from 21 to 54 billion barrels of oil and 208 to 326 trillion cubic feet of gas, corresponding to the 95-percent and 5-percent probabilities of there being more than these amounts, respectively (table 1). The mean value for oil is 35 billion barrels and for gas is 263 trillion cubic feet. Corresponding estimates for NGL range from 5 to 8 billion barrels, with a mean of 6 billion barrels. Distribution of these resources by region is shown in figure 1.

Report↗