Chemical analyses of coal from the Tongue River Member of the Fort Union Formation, Moorhead and southeastern part of the northward extension of the Sheridan coal fields, Powder River and Big Horn counties, Montana

As part of a continuing program by the U.S. Geological Survey to collect and chemically analyze representative samples of U.S. coals, 83 samples were collected from 23 core holes in the Paleocene Tongue River Member of the Fort Union Formation in Big Horn and Powder River counties, Montana. These holes are located in the Montana part of the Powder River coal region, specifically in the western part of the Moorhead coal field and on the eastern margin of the Northward Extension of the Sheridan coal field (fig. 1)