Method for determining regions for stimulation along two parallel adjacent wellbores in a hydrocarbon formation

Abstract

A method for determining along relatively uniformly spaced apart parallel first and second wellbores situated in an underground hydrocarbon-containing formation, regions within the formation, including in particular regions between such wellbores, to inject a fluid at a pressure above formation dilation pressure, to stimulate production of oil into the second of the two wellbores, and subsequently injecting fluid at pressures above formation dilation pressures at the discrete regions along such wellbores determined to be in need. An initial information-gathering procedure is conducted, wherein fluid is supplied under a pressure less than formation dilation or fracture pressure, to discrete intervals along a first wellbore, and sensors in the second wellbore measure and data is recorded regarding the ease of penetration of such fluid into the various regions of the formation intermediate the two wellbores. Regions of the formation exhibiting poor ease of fluid penetration are thereafter selected for subsequent dilation, at pressures above formation dilation pressures. Where initial fluid pressures and/or formation dilation pressures are provided in cyclic pulses, a downhole tool is disclosed for such purpose.