Contributions to economic geology in Utah 1986 (SS-69)

By: M. D. Bunnell and T. W. Taylor

In the past, the coal industry used geology primarily for exploration and delineation of coal tracts prior to mining, but in detailed mine planning and mine development, the science played a relatively minor role. With increased demands for efficient and cost-effective coal extraction, however, an understanding of the geology and depositional environments of coal bodies is crucial. Exploratory drilling can provide coal companies with limited data on roof conditions and coal characteristics in a proposed mining area, but it cannot be used to effectively map local, yet relevant, lithologic or coal quality patterns only a few meters in lateral extent. These local irregularities commonly have the greatest influence on roof stability and local changes in coal quality and recoverability. Production in the No. 3 mine has occasionally been hampered by such localized irregularities. Abrupt local variations in roof stability occur, as do localized coal bed discontinuities. In-mine geologic analyses of the roof and coal were undertaken to gain an understanding of why these local changes occur, where they occur, and what effect geologic parameters of the mine area have on roof and coal conditions.

The procedures of this study were: 1) to map roof lithology and to delineate and describe the depositional environments evidenced in rocks exposed in the mine roof; 2) to relate the roof geology to existing mine roof conditions and project expected roof conditions into proposed mine development areas; 3) to study the megascopic characteristics of the coal seam, including such characteristics as lithotype banding, methane content, cleat, rock interbeds, and coal seam discontinuities; and 4) to make a brief petrographic analysis of the coal and relate it to megascopic characteristics of the seam. This study should provide a significant addition to the existing geologic database of the No. 3 mine, as well as provide insights into the geologic considerations of coal mine roof conditions and coal seam characteristics of the area.

Other Information:
Published: 1987
Pages: 30 p.
Location: Beaver and Carbon Counties
Media Type: Paper Publication