Results 71 - 79 of 79

• Methane Migration Characteristics of the Pocahontas No. 3 Coalbed
  1/1/1972 - Reports of Investigations
  Methane-flow and pressure data taken from a mine in the Pocahontas No. 3 Coalbed are compared with flow rates from lump coal obtained in laboratory experiments. From this, it is concluded that the main source of gas is the intact coalbed rather than a "...
• Methane Emission Rate Study in a Deep Pocahontas No. 3 Coalbed Mine in Conjunction With Drilling Degasification Holes in the Coalbed
  1/1/1972 - Reports of Investigations
  A degasification experiment was conducted in a Pocahontas No. 3 Coalbed mine in Virginia. It involved (1) drilling holes in the coalbed in the outside headings of a set of five being developed in virgin area and (2) conducting a methane emission rate st...
• Methane Emission in Coal Mines: Effects of Oil and Gas Wells
  1/1/1972 - Reports of Investigations
  The method of moving averages was found useful in assessing the nature of methane emission in coal mines. Emission rates were influenced markedly by the presence of abandoned oil and gas wells in the vicinity of the mine. Such wells appeared to increase...
• The Methane Migration and Storage Characteristics of the Pittsburgh, Pocahontas No. 3, and Oklahoma Hartshorne Coalbeds
  1/1/1972 - Reports of Investigations
  Methane flows and pressures were measured in mines in the Pittsburgh, Hartshorne, and Pocahontas No. 3 Coalbeds. From the data, the permeability of each of these coalbeds was computed.
• Methane Emission Rate Studies in a Central Pennsylvania Mine
  1/1/1971 - Reports of Investigations
  The purpose of this study was to determine the characteristics of methane emissions during coal extraction by a longwall mining system. The study was conducted over 22 consecutive shifts. The average methane emission rate from the Lower Kittanning coalb...
• Methane Emission Rate Studies in a Northern West Virginia Mine
  8/1/1970 - Technical Progress Reports
  Methane emission rates were studied in a Pittsburgh coalbed mine in northern West Virginia. Air volumes and methane percentages were recorded, and time studies of the miner were made during five consecutive operating days, during which a complete cycle...
• Behavior of Coal-Gas Reservoirs
  5/1/1969 - Technical Progress Reports
  Gas occurs in coalbeds in an adsorbed and a free gas state. Adsorbed gas is stored in the micropore structure and its transport is governed by Fick's law. The free gas occurs in the fracture system and flows according to Darcy's law. These two modes of ...
• Gas Migration Characteristics of Coalbeds
  3/1/1969 - Technical Progress Reports
  The Bureau of Mines conducted drilling studies in the Pocahontas No. 3, the Pittsburgh, and a western coalbed to establish the gas migration characteristics for each.
• Removing Methane (Degasification) from the Pittsburgh Coalbed in Northern West Virginia
  1/1/1962 - Reports of Investigations
  A joint investigation by the Bureau of Mines and the Christopher Coal Co. at the Humphrey No. 7 mine, operating in the Pittsburgh coalbed in northern West Virginia, was undertaken to gain more insight concerning the hazardous emission of methane gas in ...