Patent ID: 7748458
Filing Date: 2010-07-06
Classification: E21B

Abstract:
1. A method for creating a vertical hydraulic fracture in a formation of unconsolidated and weakly cemented sediments, comprising: a. drilling a bore hole in the formation to a predetermined depth; b. installing an injection casing having at least two passages individually connected to a fracture fluid pumping system in the bore hole at the predetermined depth; c. establishing at least two pipes through which a fracture fluid can be separately injected into a corresponding number of passages within the injection casing; d. injecting a fracture fluid separately and independently into one or both of said pipes and into the passages within the injection casing and into individual opposing wings of a fracture or into only one of two wings with sufficient fracturing pressure to dilate the formation in a preferential direction and thereby initiating a vertical fracture at an azimuth orthogonal to the direction of dilation; and e. individually controlling a rate of fracture fluid injection into said pipes and through the passages into each individual opposing wing or into only one of the two wings of the initiated and propagating hydraulic fracture thereby controlling a geometry of the hydraulic fracture in either a symmetrical or an asymmetrical fashion.