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Ronald R. Charpentier

Publications and source records attributed to Ronald R. Charpentier.

At least 91 records · Page 5Linked to original sources
USGS2010

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↗
USGS2010

Assessment of undiscovered oil and gas resources of the North Caspian Basin, Middle Caspian Basin, North Ustyurt Basin, and South Caspian Basin Provinces, Caspian Sea Area, 2010

The U.S. Geological Survey estimated mean volumes of technically recoverable, conventional, undiscovered petroleum resources at 19.6 billion barrels of crude oil, 243 trillion cubic feet of natural gas, and 9.3 billion barrels of natural gas liquids for the Caspian Sea area, using a geology-based assessment methodology.

Fact Sheet↗
USGS2010

Assessment of undiscovered oil and gas resources of the Chad Basin Province, North-Central Africa

The Chad Basin Province located in north-central Africa 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 2.32 billion barrels of oil, 14.65 trillion cubic feet of natural gas, and 391 million barrels of natural gas liquids.

Fact Sheet↗
USGS2010

2010 updated assessment of undiscovered oil and gas resources of the National Petroleum Reserve in Alaska (NPRA)

Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean volumes of 896 million barrels of oil (MMBO) and about 53 trillion cubic feet (TCFG) of nonassociated natural gas in conventional, undiscovered accumulations within the National Petroleum Reserve in Alaska and adjacent State waters. The estimated volume of undiscovered oil is significantly lower than estimates released in 2002, owing primarily to recent exploration drilling that revealed an abrupt transition from oil to gas and reduced reservoir quality in the Alpine sandstone 15-20 miles west of the giant Alpine oil field. The National Petroleum Reserve in Alaska (NPRA) has been the focus of oil exploration during the past decade, stimulated by the mid-1990s discovery of the adjacent Alpine field-the largest onshore oil discovery in the United States during the past 25 years. Recent activities in NPRA, including extensive 3-D seismic surveys, six Federal lease sales totaling more than $250 million in bonus bids, and completion of more than 30 exploration wells on Federal and Native lands, indicate in key formations more gas than oil and poorer reservoir quality than anticipated. In the absence of a gas pipeline from northern Alaska, exploration has waned and several petroleum companies have relinquished assets in the NPRA. This fact sheet updates U.S. Geological Survey (USGS) estimates of undiscovered oil and gas in NPRA, based on publicly released information from exploration wells completed during the past decade and on the results of research that documents significant Cenozoic uplift and erosion in NPRA. The results included in this fact sheet-released in October 2010-supersede those of a previous assessment completed by the USGS in 2002.

Fact Sheet↗
USGS2010

Assembling probabilistic performance parameters of shale-gas wells

Shale-gas well productivity estimates in USGS assessments from 1995 to present are based on studies that require decline curve fits and analysis to a large sample or to all wells within a particular assessment unit. Probabilistic type curves can be created on nearly any size well group and were designed for use within a resource context. The probabilistic type curve was designed to improve on the familiar format of a deterministic type curve by showing the full range of production possibilities for a given group of wells. Additional information was added to make certain components, such as data density and nonproducing wells, more explicit.

Open-File Report↗
USGS2010

Applying probabilistic well-performance parameters to assessments of shale-gas resources

In assessing continuous oil and gas resources, such as shale gas, it is important to describe not only the ultimately producible volumes, but also the expected well performance. This description is critical to any cost analysis or production scheduling. A probabilistic approach facilitates (1) the inclusion of variability in well performance within a continuous accumulation, and (2) the use of data from developed accumulations as analogs for the assessment of undeveloped accumulations. In assessing continuous oil and gas resources of the United States, the U.S. Geological Survey analyzed production data from many shale-gas accumulations. Analyses of four of these accumulations (the Barnett, Woodford, Fayetteville, and Haynesville shales) are presented here as examples of the variability of well performance. For example, the distribution of initial monthly production rates for Barnett vertical wells shows a noticeable change with time, first increasing because of improved completion practices, then decreasing from a combination of decreased reservoir pressure (in infill wells) and drilling in less productive areas. Within a partially developed accumulation, historical production data from that accumulation can be used to estimate production characteristics of undrilled areas. An understanding of the probabilistic relations between variables, such as between initial production and decline rates, can improve estimates of ultimate production. Time trends or spatial trends in production data can be clarified by plots and maps. The data can also be divided into subsets depending on well-drilling or well-completion techniques, such as vertical in relation to horizontal wells. For hypothetical or lightly developed accumulations, one can either make comparisons to a specific well-developed accumulation or to the entire range of available developed accumulations. Comparison of the distributions of initial monthly production rates of the four shale-gas accumulations that were studied shows substantial overlap. However, because of differences in decline rates among them, the resulting estimated ultimate recovery (EUR) distributions are considerably different.

Open-File Report↗
USGS2010

Improved USGS methodology for assessing continuous petroleum resources using analogs

The currently used U.S. Geological Survey methodology for assessing continuous (unconventional) petroleum resources of the United States was developed in the 1990s. This methodology poorly incorporates uncertainty about the estimated ultimate recoveries (EURs). This is especially problematic for hypothetical assessment units where this may be the largest source of uncertainty that needs to be reflected in the estimates. An improved methodology estimates the uncertainty of mean EUR directly. It uses analog data that have been compiled from production histories of many developed U.S. continuous assessment units. The analog databases provide a way of estimating the variability of not just EURs but other production parameters useful in assessing continuous resources.

Open-File Report↗
USGS2009

Assessment of undiscovered oil and gas in the Arctic

Among the greatest uncertainties in future energy supply and a subject of considerable environmental concern is the amount of oil and gas yet to be found in the Arctic. By using a probabilistic geology-based methodology, the United States Geological Survey has assessed the area north of the Arctic Circle and concluded that about 30% of the world’s undiscovered gas and 13% of the world’s undiscovered oil may be found there, mostly offshore under less than 500 meters of water. Undiscovered natural gas is three times more abundant than oil in the Arctic and is largely concentrated in Russia. Oil resources, although important to the interests of Arctic countries, are probably not sufficient to substantially shift the current geographic pattern of world oil production.

Science↗
USGS2009

An estimate of recoverable heavy oil resources of the Orinoco Oil Belt, Venezuela

The Orinoco Oil Belt Assessment Unit of the La Luna-Quercual Total Petroleum System encompasses approximately 50,000 km2 of the East Venezuela Basin Province that is underlain by more than 1 trillion barrels of heavy oil-in-place. As part of a program directed at estimating the technically recoverable oil and gas resources of priority petroleum basins worldwide, the U.S. Geological Survey estimated the recoverable oil resources of the Orinoco Oil Belt Assessment Unit. This estimate relied mainly on published geologic and engineering data for reservoirs (net oil-saturated sandstone thickness and extent), petrophysical properties (porosity, water saturation, and formation volume factors), recovery factors determined by pilot projects, and estimates of volumes of oil-in-place. The U.S. Geological Survey estimated a mean volume of 513 billion barrels of technically recoverable heavy oil in the Orinoco Oil Belt Assessment Unit of the East Venezuela Basin Province; the range is 380 to 652 billion barrels. The Orinoco Oil Belt Assessment Unit thus contains one of the largest recoverable oil accumulations in the world.

Fact Sheet↗
USGS2008

Assessment of Undiscovered Oil and Gas Resources of the Permian Basin Province of West Texas and Southeast New Mexico, 2007

The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the Permian Basin Province of west Texas and southeast New Mexico. The assessment was geology based and used the total petroleum system concept. The geologic elements of a total petroleum system are petroleum source rocks (quality, source rock maturation, generation, and migration), reservoir rocks (sequence stratigraphy, petrophysical properties), and traps (trap formation and timing). This study assessed potential for technically recoverable resources in new field discoveries only; field growth (or reserve growth) of conventional oil and gas fields was not included. Using this methodology, the U.S. Geological Survey estimated a mean of 41 trillion cubic feet of undiscovered natural gas and a mean of 1.3 billion barrels of undiscovered oil in the Permian Basin Province.

Fact Sheet↗
USGS2008

Assessment of undiscovered oil and gas resources of the West Greenland-East Canada Province, 2008

The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the West Greenland-East Canada Province as part of the USGS Circum-Arctic Oil and Gas Resource Appraisal effort. The West Greenland-East Canada Province is essentially the offshore area between west Greenland and east Canada and includes Baffin Bay, Davis Strait, Lancaster Sound, and Nares Strait west of and including Kane Basin. The tectonic evolution of the West Greenland-East Canada Province led to the formation of several major structural domains that are the geologic basis for the five assessment units (AU) defined in this study. The five AUs encompass the entire province. Each AU was assessed in its entirety for undiscovered, technically recoverable (assuming absence of sea ice) oil and gas resources, but the assessment results reported here are only for those portions of each AU that are north of the Arctic Circle, as that latitude defines the area of the Circum-Arctic oil and gas assessment.

Baffin Bay, Davis Strait, Kane Basin, Lancaster So↗
USGS2008

Circum-Arctic resource appraisal: Estimates of undiscovered oil and gas north of the Arctic Circle

The U.S. Geological Survey (USGS) has completed an assessment of undiscovered conventional oil and gas resources in all areas north of the Arctic Circle. Using a geology-based probabilistic methodology, the USGS estimated the occurrence of undiscovered oil and gas in 33 geologic provinces thought to be prospective for petroleum. The sum of the mean estimates for each province indicates that 90 billion barrels of oil, 1,669 trillion cubic feet of natural gas, and 44 billion barrels of natural gas liquids may remain to be found in the Arctic, of which approximately 84 percent is expected to occur in offshore areas.

Fact Sheet↗
USGS2008

Assessment of undiscovered oil and gas resources of the Timan-Pechora Basin Province, Russia, 2008

The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the Timan-Pechora Basin Province in Russia as part of the USGS Circum-Arctic Oil and Gas Resource Appraisal program. Geologically, the Timan-Pechora Basin Province is a triangular-shaped cratonic block bounded by the northeast-southwest trending Ural Mountains and the northwest-southeast trending Timan Ridge. The northern boundary is shared with the South Barents Sea Province (fig.1). The Timan-Pechora Basin Province has a long history of oil and gas exploration and production. The first field was discovered in 1930 and, after 75 years of exploration, more than 230 fields have been discovered and more than 5,400 wells have been drilled. This has resulted in the discovery of more than 16 billion barrels of oil and 40 trillion cubic feet of gas.

Timan-Pechora Basin Province↗
USGS2008

Assessment of undiscovered oil and gas resources of the West Siberian Basin Province, Russia, 2008

The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the West Siberian Basin Province in Russia as part of the USGS Circum-Arctic Resource Appraisal program. This province is the largest petroleum basin in the world and has an areal extent of about 2.2 million square kilometers. It is a large rift-sag feature bounded to the west by the Ural fold belt, to the north by the Novaya Zemlya fold belt and North Siberian Sill, to the south by the Turgay Depression and Altay-Sayan fold belt, and to the east by the Yenisey Ridge, Turukhan-Igarka uplift, Yenisey-Khatanga Basin, and Taimyr High. The West Siberian Basin Province has a total discovered oil and gas volume of more than 360 billion barrels of oil equivalent (Ulmishek, 2000). Exploration has led to the discovery of tens of giant oil and gas fields, including the Urengoy gas field with more than 3500 trillion cubic feet of gas reserves and Samotlar oil field with reserves of nearly 28 billion barrels of oil (Ulmishek, 2003). This report summarizes the results of a reassessment of the undiscovered oil and gas potential of that part of the province north of the Arctic Circle; a previous assessment that included the entire province was completed in 2000 (Ulmishek, 2000). The total petroleum system (TPS) and assessment units (AU) defined by the USGS for the assessments in 2000 were adopted for this assessment. However, only those parts of the Aus lying wholly or partially north of the Arctic Circle were assessed for this study.

West Siberian Basin Province↗
USGS2008

Assessment of gas hydrate resources on the North Slope, Alaska, 2008

The U.S. Geological Survey (USGS) recently completed the first assessment of the undiscovered technically recoverable gas-hydrate resources on the North Slope of Alaska. Using a geology-based assessment methodology, the USGS estimates that there are about 85 trillion cubic feet (TCF) of undiscovered, technically recoverable gas resources within gas hydrates in northern Alaska.

Alaska↗
USGS2008

Assessment of undiscovered oil and gas resources of the Williston Basin Province of North Dakota, Montana, and South Dakota, 2008

Using a geology-based assessment method, the U.S. Geological Survey estimated mean undiscovered volumes of 3.8 billion barrels of undiscovered oil, 3.7 trillion cubic feet of associated/dissolved natural gas, and 0.2 billion barrels of undiscovered natural gas liquids in the Williston Basin Province, North Dakota, Montana, and South Dakota. (See “Introduction” in Fact Sheet for additional information.)

Montana, North Dakota, South Dakota↗
USGS2008

Database for Assessment Unit-Scale Analogs (Exclusive of the United States)

This publication presents a database of geologic analogs useful for the assessment of undiscovered oil and gas resources. Particularly in frontier areas, where few oil and gas fields have been discovered, assessment methods such as discovery process models may not be usable. In such cases, comparison of the assessment area to geologically similar but more maturely explored areas may be more appropriate. This analog database consists of 246 assessment units, based on the U.S. Geological Survey 2000 World Petroleum Assessment. Besides geologic data to facilitate comparisons, the database includes data pertaining to numbers and sizes of oil and gas fields and the properties of their produced fluids.

Open-File Report↗