04299295 is referenced by 52 patents and cites 11 patents.

A process for drilling spaced horizontal boreholes in a coal or other mineral deposit in excess of 1500 feet in length in a pattern determined to maximize gas removal. Directional guidance is provided by a continuous downhole survey tool connected to data display devices by an internal drill rod cable system. Directional drilling control is provided by a positive displacement motor positioned at the end of the drill string and operated by a flow of drilling fluid through the drill string from the drilling rig. The mineral strata surrounding the borehole is periodically hydrofractured to permit effective removal of the gas. The hydrofractionation is effected without removal of the drill string or survey instruments from the borehole. Upon completion of the borehole, the drill string is removed and gas which enters the borehole from the surrounding deposit is withdrawn.

Title
Process for degasification of subterranean mineral deposits
Application Number
6/119744
Publication Number
4299295
Application Date
February 8, 1980
Publication Date
November 10, 1981
Inventor
Amzi Gossard
Oklahoma City
OK, US
Agent
William G Addison
Assignee
Kerr McGee Coal Corporation
OK, US
IPC
E21B 43/26
E21B 47/024
E21B 7/08
E21B 7/04
E21B 4/02
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