Understanding hydraulic fracture variability through a penny shaped crack model for pre-rupture faults

David Cho, Gary F. Margrave, Shawn Maxwell, Mark Norton

A study was conducted to investigate the large variations in the hydraulic fracture behavior in the vicinity of faults. The process of failure was illustrated through laboratory experiments that demonstrate the formation of aligned microcracks throughout the deformation process. Using a penny shaped crack model, associated properties can be computed to investigate the response of media containing a fault that has yet to rupture. The reflectivity response for the detection of pre-rupture faults is discussed in addition to the presentation of an effective stress model for a medium containing aligned penny shaped cracks. Using the effective stress model, the observed variations can be understood from the response of the aligned cracks to a uniform normal traction applied by a pore fluid.