by R.C. Milici and T.M. Gathright, II, 8 x 11-inch soft cover book, 13 pages, includes 30 figures, 2 tables, and a glossary, 1985. Examination of geologic features that can and do lead to unsafe underground coal mining conditions. Descriptions of stable and unstable roof conditions depict different rock types, structural conditions, including folds, faults, close-spaced fractures, and slickensides encountered in a coalfield.
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