Geologic Conditions Affecting Coal Mine Ground Control in the Western United States, 1988

摘要

The Bureau of Mines recently initiated a study of geologic features that contribute to roof instability in western U.S. underground coal mines to provide information for use in ground control planning and safety hazard reduction in that region. Although the conditions found do not differ in kind from hazardous geologic conditions in the Eastern United States, they do differ in intensity of occurrence and relative importance. Three depositional features dominate where unstable roof occurs in western underground coal mines: paleochannel deposits, crevasse splay deposits, and flood basin deposits. Three structural features identified as hazardous, but not so widespread or common as the depositional hazards, are faulting, jointing, and igneous intrusions. The survey establishes a foundation for future studies aimed at reducing and preventing ground control accidents in western coal mines.