Analyses of 64 samples collected in 1975 includes tabulated whole-coal elemental compositions, oxide and trace-element analyses of ash, proximate and ultimate analyses, BTU values, forms of sulfur, index map. Available while supplies last. 112 pages. 23 figures. 11 tables. Digital PDF download. IS-07D
Beginning in 1975, the Colorado Geological Survey, in cooperation with the U.S. Geological Survey, has had an on-going project to evaluate the chemical composition of Colorado coals. This project entailed sampling of active and inactive mines and cores from drilling projects throughout the state.
This report contains data for 64 samples from 1975. A total of 64 samples (48 coal, 6 roof-rock, 7 floor-rock, and 3 partings within the coal beds) were collected, as follows: four from Canon City, five from Boulder-Weld, 29 from Yampa (Green River region), and 24 from North Park fields. A total of eight surface (strip) and two underground mines were sampled during 1975. In total, seven different coal beds, ranging in age from Late Cretaceous to early Tertiary, were sampled; all consisted of channel samples from working faces of mines.
For each sample analyses included ultimate and proximate analyses, heat values, forms of sulfur, major, minor, and trace element concentrations in both the whole coal and the ash, etc. Ranges, arithmetic and geometric means, and geometric deviations have been calculated for much of the data presented. Where available, stratigraphic information is included to aid in estimating, evaluating, and classifying Colorado coals.
This publication was supplemented by IS-10 Colorado Coal Analyses, 1976-1979, which includes an additional 295 samples from 100 locations.