Abstract: A composition and method for drilling a well into a subterranean formation containing a geothermal fluid utilizing a gas-containing aqueous drilling fluid containing both lignite and a salt of a high molecular weight acrylic polymer.

Abstract: Disclosed is a method of opening carbon-bearing beds with production wells for underground gasification wherein a production well is drilled until the top of a bed is opened up. As soon as the drilling tool enters the upper layer of the bed, the drilling is ceased and the depths of both the top and bottom of the bed are determined. Next, the drilling is resumed so as to leave a pillar of the bed at a depth where the possibility of communication between the adjacent wells by means of a fluid is assured through the bulk of the bed. On fitting a string of casing pipes in the well, the drilling of the pillar left between the shoe of the casing pipe string and the bottom of the bed goes on.Unlike the known methods, the method disclosed assures the possibility of drilling production wells in a single run without unnecessary lowering and lifting operations, and also enables an increase in the spacing of production wells, reducing at the same time the consumption of fluid per well sunk.

Abstract: The casing of a drill motor is provided with a deflection barrel free to turn thereon to position the barrel relative to the motor to apply lateral force to the side of the motor directed along any desired radius. A gravity actuated mercury potentiometer connected to the barrel provides a barrel orientation responsive electric transmitter for remote indication of the barrel orientation in the hole being drilled. An annular piston drives a key longitudinally between a straight keyway carried by the barrel and a helical keyway carried by the motor to position the barrel azimuthally about the motor axis. A manifold connected to the motor provides means for making connection to fluid and electric conduits for operating the motor, the piston, and the transmitter.

Abstract: A method of conducting foam drilling and workover operations in a bore hole penetrating a subterranean formation, particularly a high-temperature formation such as a geothermal formation, employing an aqueous solution of a N-acyl-N-methyltaurate foaming agent having the formula: ##STR1## wherein R is a straight chain alkyl group having from 9 to 15 carbon atoms; and M is an alkali metal or ammonium cation, with sodium being preferred. A particularly preferred foaming agent is sodium N-palmitoyl-N-methyltaurate.

Abstract: Laser drilling of subterranean earth formations is efficiently accomplished by directing a collimated laser beam into a bore hole in registry with the earth formation and transversely directing the laser beam into the earth formation with a suitable reflector. In accordance with the present invention, the bore hole is highly pressurized with a gas so that as the laser beam penetrates the earth formation the high pressure gas forces the fluids resulting from the drilling operation into fissures and pores surrounding the laser-drilled bore so as to inhibit deleterious occlusion of the laser beam. Also, the laser beam may be dynamically programmed with some time dependent wave form, e.g., pulsed, to thermally shock the earth formation for forming or enlarging fluid-receiving fissures in the bore.