Report issued by the U.S. Bureau of Mines on energy consumption in the western United States. A focus on coal as the primary energy source is presented. This report includes tables, graphs, maps, and illustrations.

Report issued by the U.S. Bureau of Mines on the investigations conducted on the mica deposits found in Latah County, Idaho. Characteristics and properties of the mica deposits are listed. This report includes tables, and maps.

Report from the U.S. Bureau of Mines on exploration of known cobalt ore deposits in Lemhi County, Idaho. Physical features of the area, and properties of the cobalt samples collected are presented. This report includes tables, maps, and illustrations.

Report issued by the U.S. Bureau of Mines on the sampling of chrome ore deposits in the western United States. Physical properties of the samples collected are presented. This report includes tables.

Report of investigations issued by the U.S. Bureau of Mines on the Hermada antimony deposit in southwestern Idaho. The investigations included trenching and drilling. The report contains maps of the area, and tables of data.

Report issued by the Bureau of Mines on the clay-silica deposits found in Bovill, Idaho. As stated in the abstract, "the geology, mineralogy, beneficiation, and potential uses of the clay and quartz fractions of the Bovill deposit are described" (p. 1). This report includes tables, graphs, photographs, and maps.

Report issued by the Bureau of Mines over studies conducted on phosphate resources of Idaho. Advances in the industry are discussed. This report includes tables, maps, photographs, and illustrations.

Report issued by the Bureau of Mines over a study on "stress determinations in an area known to be under high stress concentration induced by prior mining operations" (p. 2). The geology, procedures, and instrumentation are discussed. This report includes tables, illustrations, and photographs.

Report issued by the Bureau of Mines on deep mine tectonic deformities. The deep mine rock was analyzed using a petrofabric technique, and many properties were examined. This report includes photographs and illustrations.

Report issued by the Bureau of Mines on the geochemical anomalies found in the gold-antimony deposits near Stibnite, Idaho. Many samples were collected and tested through an atomic absorption method. This report includes a map.

Abstract: Researchers at the U.S. Bureau of Mines have developed personal-computer-based data acquisition, instrumentation, and mine visualization and modeling techniques to evaluate a mine accessway in a deep hard-rock mine in northern Idaho. These techniques were applied to a mine shaft in a large silver mine that has been in operation for many years. A very deep, rectangular, timber-supported shaft extending to depths exceeding 2.3 km (7,500 ft) had been deforming continuously as a result of nearby mining, resulting in operational problems. Preliminary visual observations and rock and support monitoring confirmed that severe diagonal distortion was occurring. Extensive field measurements and data analysis confirmed initial observations, provided insights into the cause of deformation, and defined a general approach to structural modeling. Computer analysis of the problem was initiated by developing a three-dimensional model of the terrain. This represented a volume of rock approximately 80 km3 (40 x 1010 ft) and an area on the surface surrounding the mine 9 km2 (3 square miles). Based on this model, a three-dimensional, finiteelement analysis was conducted to establish boundary conditions for sequentially more detailed two- and three-dimensional submodels of the shaft area. Results from the computer study are being used to develop new …