Estimated resources of non-leased federal coal, Powder River Basin, Montana and Wyoming

Maps are generated by combining digital ownership data with geologic resource estimates and other spatial coal data in a geographic information system (GIS). For example, we merged the newly compiled Federal coal ownership files with resource calculations from the 1970's for the Powder River Basin (Trent, 1986). For the first time, we are able to visually display the location of Federally owned coal in each 7.5' quadrangle along with the published coal resource estimates for those areas (fig. 8).