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Steven M. Podwysocki

Publications and source records attributed to Steven M. Podwysocki.

10 recordsLinked to original sources
USGS2011

Coal resources for the Chemard Lake (Naborton No. 2) coal zone of the lower Wilcox group (Paleocene), northwestern Louisiana

The lower part of the Wilcox Group of northwest Louisiana 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 A in apparent rank (Pierce et al., 2011), occur on the eastern part of the Sabine uplift (Figure 1). The coal zones and associated strata in the assessment area generally dip away from the axis of the Red River-Bull Bayou dome that is located in the north-central part of the Louisiana Sabine assessment area (Figure 1). This assessment area includes parts of four parishes: De Soto, Red River, Natchitoches, and Sabine (Figure 2). The assessment area was selected because of its proximity to current mining areas and the availability of stratigraphic data in the area. The assessment area is roughly 60 miles long and 15 miles wide and generally extends across the central-eastern part of the Sabine uplift in northwest Louisiana (Figure 2). More than 950 stratigraphic records from rotary and core drill holes were used to assess the coal resources of the Louisiana Sabine area. Of these, 210 are public data points and are located in or near the areas that have been permitted or proposed for surface mining (Figure 2; Appendix 1). Most of the stratigraphic data used for this assessment were provided to the U.S. Geological Survey (USGS) on a confidential basis by various coal companies for use in regional studies.

Louisiana↗
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↗