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Scott A. Kinney

Publications and source records attributed to Scott A. Kinney.

54 records · Page 3Linked to original sources
USGS2014

Coal and petroleum resources in the Appalachian basin: index maps of included studies

This chapter B.1 of U.S. Geological Survey (USGS) Professional Paper 1708 provides index maps for many of the studies described in other chapters of the report. Scientists of the USGS and State geological surveys studied coal and petroleum resources in the central and southern Appalachian structural basins. In the southern Appalachian basin, studies focused on the coal-bearing parts of the Black Warrior basin in Alabama. The scientists used new and existing geologic data sets to create a common spatial geologic framework for the fossil-fuel-bearing strata of the central Appalachian basin and the Black Warrior basin in Alabama. Digital data have been compiled into a geographic information system (GIS) that is included in chapter I.1 (Trippi and others, this volume). Shape files and related metadata for features shown in the index maps of this chapter can be downloaded from chapter I.1. The study area for the Appalachian basin resource framework study includes the fossil-fuel-bearing strata of the following States (listed alphabetically): Alabama, Kentucky, Maryland, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia. The outline of the study area is shown in figure 1; it differs from the boundary of the Appalachian Basin Province (Province 67) defined for the 1995 National Oil and Gas Assessment (NOGA) by the U.S. Geological Survey (1996a). The difference is that the study area includes regions where the Pennsylvanian coal-bearing strata crop out but does not include all of the oil- and gas-bearing strata of the Black Warrior basin, Alabama. The reasons for providing the index maps in this chapter are to show the locations of different studies, to give an overview of topics covered, and to help the user choose which chapter to read. Figures 1 and 2 show the study area outline and county names. Figure 3 shows oil and gas production in 1995 and 2005. Figure 4 shows locations of Upper Devonian sandstone oil and gas fields. Figure 5 shows major coal regions and coal fields. Figure 6 shows coal production by county. Figure 7 shows the locations of 10 cross sections of regional extent through the subsurface of the Appalachian basin. Figure 8 shows conodont alteration index sample locations and interpreted isograds for Ordovician rocks. Figure 9 shows vitrinite-reflectance data for Pennsylvanian coal in the Appalachian basin. Figure 10 shows the locations of coalbed-methane (CBM) assessment units in the study area, and figure 12 shows counties producing CBM. Figure 12 shows sulfur content of coal delivered to powerplants from coal-producing counties in the Appalachian basin and Black Warrior basin. Figure 13 shows locations of wells in Ohio and Pennsylvania where oil and gas were sampled in Lower Silurian reservoirs. Figure 14 shows the Conasauga-Rome/Conasauga Total Petroleum System and selected wells in the Rome trough in Kentucky and West Virginia having oil and gas production and shows. Figure 15 shows the locations of samples from Silurian reservoirs in Kentucky, New York, Ohio, Pennsylvania, and West Virginia; the samples yielded total organic carbon data. Figure 16 shows the locations of the Ben Hur and Rose Hill oil fields, Virginia, and the Swan Creek oil field, Tennessee. The one index map that is not shown is the areal extent of the shale gas plays in the basin. The extents of the plays can be found in Coleman and others (this volume, chap. G.13).

Appalachian basin↗
USGS2014

Geographic information system (GIS)-based maps of Appalachian basin oil and gas fields

One of the more recent maps of Appalachian basin oil and gas fields (and the adjoining Black Warrior basin) is the U.S. Geological Survey (USGS) compilation by Mast and others (1998) (see Trippi and others, this volume, chap. I.1). This map is part of a larger oil and gas field map for the conterminous United States that was derived by Mast and others (1998) from the Well History Control System (WHCS) database of Petroleum Information, Inc. (now IHS Energy Group). Rather than constructing the map from the approximately 500,000 proprietary wells in the Appalachian and Black Warrior part of the WHCS database, Mast and others (1998) subdivided the region into a grid of 1-mi 2 (square mile) cells and allocated an appropriate type of hydrocarbon production (oil production, gas production, oil and gas production, or explored but no production) to each cell. Each 1-mi 2 cell contains from 0 to 5 or more exploratory and (or) development wells. For example, if the wells in the 1-mi 2 cell consisted of three oil wells, one gas well, and one dry well, then the cell would be characterized on the map as an area of oil and gas production. The map by Mast and others (1998) accurately shows the distribution and types of hydrocarbon accumulation in the Appalachian and Black Warrior basins, but it does not show the names of individual fields. To determine the locality and name of individual oil and gas fields, one must refer to State oil and gas maps (for example, Harper and others, 1982), which are generally published at scales of 1:250,000 or 1:500,000 (see References Cited), and (or) published journal articles. Other recent USGS Appalachian basin oil and gas field maps show the distribution of oil and gas production with a cell size as small as 0.25 mi 2 , such as the maps converted by Trippi and others (this volume, chap. I.1) from proprietary well-location maps used in the USGS 2002 assessment of oil and gas resources of the Appalachian basin (Milici and others, 2003). Another set of Appalachian basin oil and gas cell maps (based on a cell size of 0.25 mi 2 ) was created for the USGS 1995 National Assessment of United States Oil and Gas Resources (Gautier and others, 1995; Beeman and others, 1996). Between 1991 and 1994, R.T. Ryder (with R.E. Mattick, J.B. Roen, and J.R. San Filipo, USGS, Reston, Va.) compiled oil and gas fields on stable-base mylar greenline base maps (scale 1:500,000) for selected plays in the Appalachian basin. These map compilations included field names and field numbers where assigned by State agencies. The purpose of the maps was to provide supporting data for the USGS 1995 National Assessment of United States Oil and Gas Resources (Gautier and others, 1995). In particular, the greenline oil and gas field maps were linked, where possible, with production data from State records and (or) published literature in order to determine ultimate sizes for conventional fields and estimated ultimate recovery (EUR) values for wells in continuous accumulations (for definitions of the conventional and continuous terminology, see USGS National Oil and Gas Assessment Team, 1995; Schmoker, 1997; Schenk and Pollastro, 2002). This approach was used in the 1995 national oil and gas assessment because ultimate field size and EUR data were unavailable in the Appalachian region from Petroleum Information, Inc., and other commercial sources. In 2006 and 2007, the greenline Appalachian basin field maps were digitized under the supervision of Scott Kinney and converted to geographic information system (GIS) files for chapter I.1 (this volume). By converting these oil and gas field maps to a digital format and maintaining the field names where noted, they are now available for a variety of oil and gas and possibly carbon-dioxide sequestration projects. Having historical names assigned to known digitized conventional fields provides a convenient classification scheme into which cumulative production and ultimate field-size databases can be organized. Moreover, as exploratory and development drilling expands across the basin, many previously named fields that were originally treated as conventional fields have evolved into large, commonly unnamed continuous-type accumulations. These new digital maps will facilitate a comparison between EUR values from recently drilled, unnamed parts of continuous accumulations and EUR values from named fields discovered early during the exploration cycle of continuous accumulations.

Appalachian basin↗
USGS2014

Coal and coalbed-methane resources in the Appalachian and Black Warrior basins: maps showing the distribution of coal fields, coal beds, and coalbed-methane fields

The maps contained in this chapter show the locations of coal fields, coal beds assessed by the U.S. Geological Survey (USGS) in 2000, and coalbed-methane fields in the central and southern Appalachian basin study areas, which include the coal-producing parts of the Black Warrior basin. The maps were compiled and modified from a variety of sources such as Tully (1996), Northern and Central Appalachian Basin Coal Regions Assessment Team (2001), Hatch and others (2003), Milici (2004), and unpublished data from the State geological surveys of Pennsylvania, West Virginia, Virginia, and Alabama. The terms “coalbed methane” and “coal-bed gas” are used interchangeably in this report. All of the figures are located at the end of this report. The Appalachian basin historically has been subdivided into three coal regions on the basis of regional geologic structure and stratigraphy: the northern region in western Pennsylvania, eastern Ohio, western Maryland, and northern West Virginia; the central region in west-central and southwestern West Virginia, eastern Kentucky, northern Tennessee, and southwestern Virginia; and the southern region in southern Tennessee, northern Alabama, and northwestern Georgia. The Appalachian basin is one of the most important coal-producing regions in the Nation and the world, and coal has been mined there throughout the last three centuries. The coal is primarily used within the Eastern United States for electrical power generation, but some of it is suitable for metallurgical uses. In 2008, the Appalachian basin produced about 320 million short tons of coal from 1,278 underground and surface coal mines (Energy Information Agency, 2009a). Coalbed-methane production in the Appalachian basin coal regions is an increasingly important resource. In 2008, 247 billion cubic feet (bcf) of coalbed methane was produced in the basin from Alabama (107 bcf), Virginia (101 bcf), West Virginia (28 bcf), and Pennsylvania (11 bcf) (Energy Information Agency, 2009b). Coalbed-methane exploration is ongoing in all of the States in the Appalachian basin coal regions, and production is expected to increase. The study area for most reports in this volume is the Appalachian basin. The term “Appalachian basin study area” (shortened from “Appalachian basin geologic framework study area”) includes all of the Appalachian Basin Province (Province 67) and part of the neighboring Black Warrior Basin Province (Province 65) of Dolton and others (1995). The boundaries for these two provinces and the study area are shown on figure 1.

Appalachian basin↗
USGS2014

Digital data in support of studies and assessments of coal and petroleum resources in the Appalachian basin

The Appalachian basin is a mature basin containing abundant oil, gas, and coal resources. Its fossil-fuel-bearing strata range in age from Cambrian to Permian and extend over the States of New York, Pennsylvania, Maryland, Ohio, West Virginia, Virginia, Kentucky, Tennessee, Georgia, and Alabama. The basin has provided abundant fossil fuels to support the Nation’s economic growth for at least 150 years and U.S. Geological Survey (USGS) assessments suggest that substantial untapped resources remain. A merger of new and old geologic data and ideas is required to locate and extract those remaining resources. This chapter brings together abundant existing datasets in a common and integrated spatial format to advance our understanding of the distribution, geologic framework, burial history, and geochemical character of the basin’s oil, gas, and coal resources. These datasets support the information and findings in chapters B through G of this volume, which include (1) geologic cross sections, seismic profiles, and burial history models that document the depositional and structural framework of the basin; (2) assessments of Carboniferous coal-bed gas and Devonian shale gas; (3) studies about the distribution of oil, gas, and coal fields and the geochemistry of natural gas and oil; and (4) a history of fossil-fuel production in the basin. The data that supported these studies were refined and made more accessible using geographic information system (GIS) tools. The following types of data are included: (1) the bedrock geology of States included within the boundary of the Appalachian basin, (2) the locations of oil and gas wells and fields, (3) data produced for the National Oil and Gas Assessment, and (4) the stratigraphy, geochemistry, and production of coal. Data layers are available in shapefile and Zipped Keyhole Markup Language (KMZ) formats, which can be viewed using ArcGIS, Google Earth, or any software package that supports these data formats. Metadata for these datasets are available in HTML and XML formats. Metadata files contain information about the sources of data used to create the dataset, the creation process steps, the data quality, the geographic coordinate system and horizontal datum used for the dataset, the values of attributes used in the dataset table, information about the publication and the publishing organization, and other information that may be useful to the reader. All links in the metadata were valid at the time of compilation. Some of these links may no longer be valid. No attempt has been made to determine the new online location (if one exists) for the data.

Appalachian basin↗
USGS2013

Regional maps of subsurface geopressure gradients of the onshore and offshore Gulf of Mexico basin

The U.S. Geological Survey created a comprehensive geopressure-gradient model of the regional pressure system spanning the onshore and offshore Gulf of Mexico basin, USA. This model was used to generate ten maps that included (1) five contour maps characterizing the depth to the surface defined by the first occurrence of isopressure gradients ranging from 0.60 psi/ft to 1.00 psi/ft, in 0.10-psi/ft increments; and (2) five supporting maps illustrating the spatial density of the data used to construct the contour maps. These contour maps of isopressure-gradients at various increments enable the identification and quantification of the occurrence, magnitude, location, and depth of the subsurface pressure system, which allows for the broad characterization of regions exhibiting overpressured, underpressured, and normally pressured strata. Identification of overpressured regions is critical for exploration and evaluation of potential undiscovered hydrocarbon accumulations based on petroleum-generation pressure signatures and pressure-retention properties of reservoir seals. Characterization of normally pressured regions is essential for field development decisions such as determining the dominant production drive mechanisms, evaluating well placement and drainage patterns, and deciding on well stimulation methods such as hydraulic fracturing. Identification of underpressured regions is essential for evaluating the feasibility of geological sequestration and long-term containment of fluids such as supercritical carbon dioxide for alternative disposal methods of greenhouse gases. This study is the first, quantitative investigation of the regional pressure systems of one of the most important petroleum provinces in the United States. Although this methodology was developed for pressure studies in the Gulf of Mexico basin, it is applicable to any basin worldwide.

Open-File Report↗
USGS2012

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↗
USGS2012

Geology and sequence stratigraphy of undiscovered oil and gas resources in conventional and continuous petroleum systems in the Upper Cretaceous Eagle Ford Group and related strata, U.S. Gulf Coast Region

The U.S. Geological Survey (USGS) recently assessed the technically recoverable undiscovered oil and gas onshore and in State waters of the Gulf Coast region of the United States. The USGS defined three assessment units (AUs) with potential undiscovered conventional and continuous oil and gas resources in Upper Cretaceous (Cenomanian to Turonian) strata of the Eagle Ford Group and correlative rocks. The assessment is based on geologic elements of a total petroleum system, including hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and traps (formation, timing, and seals). Conventional oil and gas undiscovered resources are in updip sandstone reservoirs in the Upper Cretaceous Tuscaloosa and Woodbine Formations (or Groups) in Louisiana and Texas, respectively, whereas continuous oil and continuous gas undiscovered resources reside in the middip and downdip Upper Cretaceous Eagle Ford Shale in Texas and the Tuscaloosa marine shale in Louisiana. Conventional resources in the Tuscaloosa and Woodbine are included in the Eagle Ford Updip Sandstone Oil and Gas AU, in an area where the Eagle Ford Shale and Tuscaloosa marine shale display vitrinite reflectance (Ro) values less than 0.6%. The continuous Eagle Ford Shale Oil AU lies generally south of the conventional AU, is primarily updip of the Lower Cretaceous shelf edge, and is defined by thermal maturity values within shales of the Eagle Ford and Tuscaloosa that range from 0.6 to 1.2% Ro. Similarly, the Eagle Ford Shale Gas AU is defined downdip of the shelf edge where source rocks have Ro values greater than 1.2%. For undiscovered oil and gas resources, the USGS assessed means of: 1) 141 million barrels of oil (MMBO), 502 billion cubic feet of natural gas (BCFG), and 4 million barrels of natural gas liquids (MMBNGL) in the Eagle Ford Updip Sandstone Oil and Gas AU; 2) 853 MMBO, 1707 BCFG, and 34 MMBNGL in the Eagle Ford Shale Oil AU; and 3) 50,219 BCFG and 2009 MMBNGL in the Eagle Ford Shale Gas AU.

Louisiana;Texas↗
USGS2012

Distribution of regional pressure in the onshore and offshore Gulf of Mexico basin, USA

The U.S. Geological Survey (USGS) has created a comprehensive geopressure-gradient model of the regional pressure system spanning the onshore and offshore portions of the Gulf of Mexico, USA. The model was used to generate ten maps: five contour maps (Maps 1A - 5A) characterize the depth to the surface defined by the first occurrence of isopressure-gradients ranging from 0.60 psi/ft to 1.00 psi/ft, in 0.10-psi/ft increments, and five supporting maps (Maps 1B - 5B) display the spatial density of the data used to construct the isopressure-gradient maps. The boundary of the geopressure-gradient model represents the maximum extent of the calculated pressure-gradient data. The regional investigation, however, encompassed an area defined by the USGS Upper Jurassic-Cretaceous-Tertiary Composite Total Petroleum System Boundary, and the availability of offshore data. A description of the geopressure-gradient model, including related mathematical derivations, the data-quality control methodology, linear pressure interpolation calculations, and contouring algorithms is provided by Burke et al. (in press [a]; in press [b]); these references, as well as a summary of the geopressure-gradient model, are supplied in the online documentation .

Gulf of Mexico↗
USGS2012

Regional map of the 0.70 psi/ft pressure gradient and development of the regional geopressure-gradient model for the onshore and offshore Gulf of Mexico basin, USA

Characterization of the regional pressure system in the Gulf of Mexico basin is critical for assessing the occurrence of undiscovered petroleum resources, evaluating areas with potential pressure-related production, identifying potential pressure-related geohazard issues, evaluating hydrocarbon reservoir-seal integrity, and determining the feasibility of geological sequestration and long-term containment of fluids.

Gulf of Mexico↗
USGS2011

Coal database for Cook Inlet and North Slope, Alaska

This database is a compilation of published and nonconfidential unpublished coal data from Alaska. Although coal occurs in isolated areas throughout Alaska, this study includes data only from the Cook Inlet and North Slope areas. The data include entries from and interpretations of oil and gas well logs, coal-core geophysical logs (such as density, gamma, and resistivity), seismic shot hole lithology descriptions, measured coal sections, and isolated coal outcrops.

Data Series↗
USGS2011

Digital archive of drilling mud weight pressures and wellbore temperatures from 49 regional cross sections of 967 well logs in Louisiana and Texas, onshore Gulf of Mexico basin

This document provides the digital archive of in-situ temperature and drilling mud weight pressure data that were compiled from several historical sources. The data coverage includes the states of Texas and Louisiana in the Gulf of Mexico basin. Data are also provided graphically, for both Texas and Louisiana, as plots of temperature as a function of depth and pressure as a function of depth. The minimum, arithmetic average, and maximum values are tabulated for each 1,000-foot depth increment for temperature as well as pressure in the Texas and Louisiana data.

Open-File Report↗
USGS2010

After a century: Revised Paleogene coal stratigraphy, correlation, and deposition, Powder River Basin, Wyoming and Montana

The stratigraphy, correlation, mapping, and depositional history of coal-bearing strata in the Paleogene Fort Union and Wasatch Formations in the Powder River Basin were mainly based on measurement and description of outcrops during the early 20th century. Subsequently, the quality and quantity of data improved with (1) exploration and development of oil, gas, and coal during the middle 20th century and (2) the onset of coalbed methane (CBM) development during the late 20th and early 21st centuries that resulted in the drilling of more than 26,000 closely spaced wells with accompanying geophysical logs. The closeness of the data control points, which average 0.5 mi (805 m) apart, made for better accuracy in the subsurface delineation and correlation of coal beds that greatly facilitated the construction of regional stratigraphic cross sections and the assessment of resources. The drillhole data show that coal beds previously mapped as merged coal zones, such as the Wyodak coal zone in the Wyoming part of the Powder River Basin, gradually thinned into several discontinuous beds and sequentially split into as many as 7 hierarchical orders westward and northward. The thinning and splitting of coal beds in these directions were accompanied by as much as a ten-fold increase in the thicknesses of sandstone-dominated intervals within the Wyodak coal zone. This probably resulted from thrust loading by the eastern front of the Bighorn uplift accompanied by vertical displacement along lineaments that caused subsidence of the western axial part of the Powder River Basin during Laramide deformation in Late Cretaceous and early Tertiary time. Accommodation space was thereby created for synsedimentary alluvial infilling that controlled thickening, thinning, splitting, pinching out, and areal distribution of coal beds. Equally important was differential subsidence between this main accommodation space and adjoining areas, which influenced the overlapping, for example, of the Dietz coal zone in Montana, over the Wyodak coal zone in Wyoming. Correlation in a circular track of the Wyodak coal zone in the southern part of the basin also demonstrates overlapping with lower coal zones. Recognition of this stratigraphic relationship has led to revision of the correlations and nomenclature of coal beds because of inconsistency within these zones as well as those below and above them, which have long been subjects of controversy. Also, it significantly changes the traditional coal bed-to-bed correlations, and estimates of coal and coalbed methane resources of these coal zones due to thinning and pinching out of beds. More notably, thickness isopach, orientation, and distribution of the merged Wyodak coal bodies in the south-southeast part of the basin suggest that differential movement of lineament zones active during the Cretaceous was not a major influence on coal accumulation during the Paleocene. Improved knowledge of alluvial depositional environments as influenced by external and internal paleotectonic conditions within the Powder River Basin permits more accurate correlation, mapping, and resource estimation of the Fort Union and Wasatch coal beds. The result is a better understanding of the sedimentology of the basin infill deposits in relation to peat bog accumulation.

Montana, Wyoming↗
USGS2008

GIS Representation of Coal-Bearing Areas in North, Central, and South America

Worldwide coal consumption and international coal trade are projected to increase in the next several decades (Energy Information Administration, 2007). A search of existing literature indicates that in the Western Hemisphere, coal resources are known to occur in about 30 countries. The need exists to be able to depict these areas in a digital format for use in Geographic Information System (GIS) applications at small scales (large areas) and in visual presentations. Existing surficial geology GIS layers of the appropriate geologic age have been used as an approximation to depict the extent of coal-bearing areas in North, Central, and South America, as well as Greenland (fig. 1). Global surficial geology GIS data were created by the U.S. Geological Survey (USGS) for use in world petroleum assessments (Hearn and others, 2003). These USGS publications served as the major sources for the selection and creation of polygons to represent coal-bearing areas. Additional publications and maps by various countries and agencies were also used as sources of coal locations. GIS geologic polygons were truncated where literature or hardcopy maps did not indicate the presence of coal. The depicted areas are not adequate for use in coal resource calculations, as they were not adjusted for geologic structure and do not include coal at depth. Additionally, some coal areas in Central America could not be represented by the mapped surficial geology and are shown only as points based on descriptions or depictions from scientific publications or available maps. The provided GIS files are intended to serve as a backdrop for display of coal information. Three attributes of the coal that are represented by the polygons or points include geologic age (or range of ages), published rank (or range of ranks), and information source (published sources for age, rank, or physical location, or GIS geology base).

Open-File Report↗
USGS2005

Preliminary integrated geologic map databases for the United States: Delaware, Maryland, New York, Pennsylvania, and Virginia

The growth in the use of Geographic Information Systems (GIS) has highlighted the need for regional and national digital geologic maps attributed with age and lithology information. Such maps can be conveniently used to generate derivative maps for purposes including mineral-resource assessment, metallogenic studies, tectonic studies, and environmental research. This Open-File Report is a preliminary version of part of a series of integrated state geologic map databases that cover the entire United States. The only national-scale digital geologic maps that portray most or all of the United States for the conterminous U.S. are the digital version of the King and Beikman (1974a, b) map at a scale of 1:2,500,000, as digitized by Schruben and others (1994) and the generalized digital version (Reed and Bush, 2004) of the Geologic Map of North America (Reed and others, 2005a, b) compiled at a scale of 1:5,000,000. The present series of maps is intended to provide the next step in increased detail. State geologic maps that range in scale from 1:100,000 to 1:1,000,000 are available for most of the country, and digital versions of these state maps are the basis for this product. In a few cases, new digital compilations were prepared (e.g. Ohio, South Carloina, South Dakota) or existing paper maps were digitized (e.g. Kentucky, Texas). Also as part of this series, new regional maps for Alaska and Hawaii are being compiled and ultimately new state maps will be produced. The digital geologic maps are presented in standardized formats as ARC/INFO export (.e00) files and as ArcView shape (.shp) files. Accompanying these spatial databases are a set of five supplemental attribute tables that relate the map units to detailed lithologic and age information. The maps for the CONUS have been fitted to a common set of state boundaries based on the 1:100,000 topographic map series of the United States Geological Survey (USGS). When the individual state maps are merged, the combined attribute tables can be used directly with the merged maps to make derivative maps. No attempt has been made to reconcile differences in mapped geology across state lines.

Delaware, Maryland, New York, Pennsylvania, Virgin↗
USGS2004

Alaska coal geology, resources, and coalbed methane potential

Estimated Alaska coal resources are largely in Cretaceous and Tertiary rocks distributed in three major provinces. Northern Alaska-Slope, Central Alaska-Nenana, and Southern Alaska-Cook Inlet. Cretaceous resources, predominantly bituminous coal and lignite, are in the Northern Alaska-Slope coal province. Most of the Tertiary resources, mainly lignite to subbituminous coal with minor amounts of bituminous and semianthracite coals, are in the other two provinces. The combined measured, indicated, inferred, and hypothetical coal resources in the three areas are estimated to be 5,526 billion short tons (5,012 billion metric tons), which constitutes about 87 percent of Alaska's coal and surpasses the total coal resources of the conterminous United States by 40 percent. Coal mining has been intermittent in the Central Alaskan-Nenana and Southern Alaska-Cook Inlet coal provinces, with only a small fraction of the identified coal resource having been produced from some dozen underground and strip mines in these two provinces. Alaskan coal resources have a lower sulfur content (averaging 0.3 percent) than most coals in the conterminous United States are within or below the minimum sulfur value mandated by the 1990 Clean Air Act amendments. The identified resources are near existing and planned infrastructure to promote development, transportation, and marketing of this low-sulfur coal. The relatively short distances to countries in the west Pacific Rim make them more exportable to these countries than to the lower 48 States of the United States. Another untapped but potential resource of large magnitude is coalbed methane, which has been estimated to total 1,000 trillion cubic feet (28 trillion cubic meters) by T.N. Smith 1995, Coalbed methane potential for Alaska and drilling results for the upper Cook Inlet Basin: Intergas, May 15 - 19, 1995, Tuscaloosa, University of Alabama, p. 1 - 21.

Data Series↗