Abstract: System and methods for creating shaped, non-circular boreholes in rocks especially for use with geothermal heat pump applications and for increasing wellbore support in applications such as horizontal oil and gas drilling are described. The systems and methods when applied to geothermal heat pumps create an elliptical shaped hole that is optimized for placing heat transfer tubes with a minimum of grout used. The significantly reduced cross-sectional area of the elliptical borehole also increases the overall drilling rate in rock and especially in hard rocks. In horizontal hard-rock drilling, creation of a horizontal non-circular borehole or modification of a circular borehole to a non-circular geometry is used to stabilize the borehole prior to casing insertion, and may also allow the use of lower mud pressures improving drilling rates. The system uses a non-contacting drilling system which in one embodiment uses a supersonic flame jet drilling system with a movable nozzle that swings between pivot points.

Abstract: A compression cell for rock or soil core samples applies and restores lithostatic or overburden pressure to core samples extracted from wells drilled deep into the earth. A method of applying lithostatic pressure to a core sample is disclosed along with the apparatus which effects the application. The cell construction that maintains the litho static pressure and the process of utilizing the cell and sample under essentially deep earth ambient conditions are set forth.