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Claire E. Aubourg

Publications and source records attributed to Claire E. Aubourg.

8 recordsLinked to original sources
USGS2011

A review of Alabama lignite deposits

This review of Alabama lignite deposits is a part of the U.S. Geological Survey (USGS) National Coal Resource Assessment (NCRA) of the Gulf Coast region (see Ruppert et al., 2002; Dennen, 2009; and other chapters of this publication). Because lignite is not currently mined in Alabama, a detailed assessment of the state was not made, and only a review is presented in this chapter. Lignite beds are found in several stratigraphic horizons within the Paleocene Midway and Paleocene to Eocene Wilcox Groups in the Gulf Coastal Plain of Alabama (Figure 1). There are three main near-surface (less than 250 ft of overburden) lignite deposits in Alabama. In the Midway Group, the Oak Hill lignite deposit occurs in the upper part of the Oak Hill Member of the Naheola Formation (Figure 2). In the Wilcox Group, the Gravel Creek and the Tuscahoma lignite deposits occur in the Coal Bluff Marl Member of the Nanafalia Formation and the Tuscahoma Sand Member of the Tuscahoma Sand Formation, respectively (Figure 2). The Gravel Creek lignite occurs in central and eastern Alabama, and the Oak Hill and Tuscahoma Sand lignites occur in southwest Alabama. Eighty-five percent of this lignite may be recoverable by surface mining methods (Tolson, 1985). The total amount of lignite reported as a reserve by the state is over 4.7 billion short tons (Self et al., 1978).

Alabama↗
USGS2011

Coal resources for part of the Wilcox group (Paleocene through Eocene), central Texas

The Wilcox Group of central Texas contains shallow (less than 500 ft) coal deposits that are mined for use in mine-mouth electric power generating plants. These coal deposits range in apparent rank from lignite to sub-bituminous (Pierce et al., 2011) and are similar in rank and composition to shallow coal deposits in the northeast and south Texas areas (Figure 1). The coal zones and associated strata in the central Texas assessment area generally dip to the southeast toward the Gulf of Mexico coastline and basin center. The central Texas resource assessment area includes parts of eight counties (Figure 2). The assessment area was selected to encompass current mining areas and areas with available subsurface stratigraphic data. The assessment area is roughly 160 miles long and 5 to 25 miles wide and generally follows the outcrop of the Paleocene to Eocene Wilcox Group in central Texas (Figures 1, 2). Approximately 1800 subsurface stratigraphic records from rotary and core drill holes were used to assess the resources of the central Texas assessment area. Of the 1800 drill holes, only 167 are public data points and are primarily located in the areas that have been permitted for surface mining (Figure 2; Appendix 1). The remaining 1632 drill holes, which are distributed throughout the assessment area, were provided to the U.S. Geological Survey (USGS) on a confidential basis by various coal companies for use in regional studies.

Texas↗
USGS2011

Coal resources for part of the Wilcox group (Paleocene-Eocene), northeast Texas

The Wilcox Group of northeast Texas contains shallow (less than 500 ft) coal deposits that are mined for use in mine-mouth electric power generating plants. The coal deposits, which are lignite in apparent rank (Pierce et al., 2011), are separated from similar shallow coal deposits in the Sabine uplift area by the East Texas Basin (Figure 1). The coal zones and associated strata in the northeast assessment area generally dip to the south and southeast at 28 or less toward the axis of the East Texas Basin. The northeast Texas resource assessment area includes parts of nine counties (Figure 2).

Texas↗
USGS2002

Preliminary evaluation of the coal resources for part of the Wilcox Group (Paleocene through Eocene), central Texas

The Wilcox Group of central Texas contains shallow (<500 ft) coal deposits that are mined for use in mine-mouth electric power generating plants. These coal deposits range in apparent rank from lignite to sub-bituminous (Tewalt, 1986), and are similar in rank and composition to shallow coal deposits in the northeast and south Texas areas (fig. 1). The coal zones and associated strata in the central Texas study area generally dip to the southeast toward the Gulf of Mexico coastline and basin center. The central Texas resource assessment area includes parts of eight counties (fig. 2). The assessment area was selected to encompass current mining areas and because of the availability of subsurface stratigraphic data in the area. The assessment area is roughly 160 miles long and 5 to 25 miles wide and generally follows the outcrop of the Paleocene - Eocene Wilcox Group in central Texas (figs. 1 and 2). Approximately 1,800 subsurface stratigraphic records from rotary and core drill holes were used to assess the resources of the central Texas assessment area. Of the 1,800 drill holes, only 168 are public data points and are primarily located in the areas that have been permitted for surface mining (fig. 2; Appendix 1). The remaining 1632 drill holes, which are distributed throughout the assessment area, were provided to the U.S. Geological Survey (USGS) on a confidential basis by various coal companies for use in regional studies. Nine coal zones were identified and assessed in the central Texas assessment area. Several other coal zones (as many as 9 unassessed zones) were identified but were not assessed due to the thinness of the coal beds or the lack of deep stratigraphic data (fig. 3). A total of 7.7 billion short tons of coal was identified in this assessment that excluded the resources within current coal mine lease areas (fig. 2). Corresponding maps were constructed to show the overburden, structure contour of the top of the coal zone, and cumulative coal-zone thickness for each of the nine coal zones. Warwick and Crowley (1995) offer a discussion of the general geologic setting and stratigraphy of the central Texas study area, and Tewalt (1986) presents a discussion of the coal quality aspects of the central Texas study area.

Open-File Report↗