Patent ID: 7784545
Filing Date: 2010-08-31
Classification: E21B,F24T,Y02E

Abstract:
1. A method of forming fractures in a subsurface formation having a substantially vertical borehole, at least one substantially horizontal fracturing borehole selectively in fluid communication with the substantially vertical borehole, at least one substantially horizontal injection borehole selectively in fluid communication with the substantially vertical borehole, and at least one substantially horizontal production borehole selectively in fluid communication with the substantially vertical borehole, wherein the substantially horizontal boreholes are spaced apart from one another, the method comprising the steps of: preventing substantial fluid communication between the substantially vertical borehole and each of the at least one substantially horizontal injection borehole and the at least one substantially horizontal production borehole; permitting substantial fluid communication between the substantially vertical borehole and the at least one substantially horizontal fracturing borehole; providing an initial quantity of liquified gas into the at least one substantially horizontal fracturing borehole such that the liquified gas communicates with the formation; and allowing the initial quantity of liquified gas to vaporize in a portion of the at least one substantially horizontal fracturing borehole whereby a resulting increase in pressure in the at least one fracturing borehole forms fractures in a portion of the formation.