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January 1, 2011

The National Coal Resource Assessment (NCRA) team of the U.S. Geological Survey (USGS) has assessed the quantity and quality of coal beds and zones that could be mined during the next 20 years or more. Geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States: the Appalachian Basin, Illinois Basin, Northern Rocky Mountains and Great Plains, Colorado Plateau, and the Gulf of Mexico Coastal Plain, (Gulf Coast) (Figure 1). In particular, the NCRA assessed coal-quality information and characterized environmentally significant trace elements, such as arsenic and mercury, that are defined in and administered by 1990 Clean Air Act Amendments (U.S. Environmental Protection Agency, 1990). The results of various USGS coal assessment efforts may be found at:, and a summary of the results from all assessment areas can be found in Ruppert et al. (2002) and Dennen (2009).

Publication Year 2011
Title Introduction
Authors Peter D. Warwick, Robert W. Hook, John R. SanFilipo
Publication Type Book Chapter
Publication Subtype Book Chapter
Series Title AAPG Studies in Geology
Index ID 70192776
Record Source USGS Publications Warehouse
USGS Organization Eastern Energy Resources Science Center