Results 211 - 220 of 270

• Methane Accumulations in Coal Mine Roof Cavities
  1/1/1978 - Reports of Investigations
  The Bureau of Mines investigated the presence and extent of methane accumulations in mine roof cavities using a full-scale mine model. Methane was released at a constant rate into the roof of a cavity built onto a 700-ft wind tunnel.
• Directionally Controlled Drilling To Horizontally Intercept Selected Strata, Upper Freeport Coalbed, Greene County, Pa.
  1/1/1977 - Reports of Investigations
  A 3-inch pilot hole was directionally drilled to intercept the Freeport coalbed horizon horizontally at Mather, Pennsylvania, as part of a Bureau of Mines degasification project. The original concept was to continue the horizontal drilling into the coal...
• Estimating Methane Content of Bituminous Coalbeds From Adsorption Data
  1/1/1977 - Reports of Investigations
  The Bureau of Mines estimated the methane content of a coal, which depends primarily upon rank and pressure, from the adsorption equation V = kPn, where k and n are constants related to rank.
• Methane Absorption in Oil Shale and Its Potential Mine Hazard
  1/1/1977 - Reports of Investigations
  The Bureau of Mines made laboratory absorption measurements on oil shale samples, which showed that the amount of methane absorbed is proportional to pressure and oil yield, and can be much larger than would be predicted based solely on porosity. Oil sh...
• Geology and Methane Content of the Upper Freeport Coalbed in Fayette County, Pa.
  1/1/1977 - Reports of Investigations
  The Upper Freeport coalbed was studied in Fayette County, Pennsylvania. This coalbed lies about 650 feet below the Pittsburgh coalbed and contains the largest remaining reserves of any coalbed in the county.
• Effects of Hydraulic Stimulation on Coalbeds and Associated Strata
  1/1/1977 - Reports of Investigations
  In studies conducted by the Bureau of Mines, two test areas were hydraulically stimulated and exposed by mining: one in the Pittsburgh coalbed at the Vesta No. 5 Mine, Washington County, Pennsylvania; and one in the Illinois No. 6 Coalbed at the Inland ...
• Methane Emissions from Four Working Places in the Beckley Mine, Raleigh County, W. Va.
  1/1/1977 - Reports of Investigations
  The Beckley Mine is one of five new mines in a heretofore unmined portion of the Beckley coalbed. The remoteness of these new mines from prior mining and their greater overburden preclude applying methane emission experience obtained in the old mines. F...
• Hydraulic Stimulation of a Surface Borehole for Gob Degasification
  1/1/1977 - Reports of Investigations
  The Bureau of Mines evaluated the hydraulic stimulation of a gob degasification borehole to determine if this procedure would aid in degasifying a longwall panel.
• Methods of Determining the Orientations of Bedrock Fracture Systems in Southwestern Pennsylvania and Northern West Virginia
  1/1/1977 - Reports of Investigations
  This Bureau of Mines report describes photo-lineaments obtained from stereoscopic examination of vertical aerial photographs and by the ronchi grating study of aerial photoindex sheets. The photo- lineaments are compared with the trends of oriented frac...
• Water Infusion of Coalbeds for Methane and Dust Control
  1/1/1977 - Reports of Investigations
  This Bureau of Mines report deals with water infusion of coalbeds, which can control methane emission at face areas during developmental mining and which may sometimes suppress dust. Studies show that water infused into the coalbed flows through the fra...