A Method for Determining the Orientation of A Water Injection Induced Fracture

The objective of most all waterfloods is to inject water at rates as high as possible without fracturing the formation. Sometimes fractures of limited length are required to reach beyond near wellbore damage of an injection well. However, a fracture that grows to larger distances may drastically affect the volumetric sweep efficiency of a waterflood pattern. As waterflood projects mature, increasingly higher water rates are necessary to maintain oil rates. Increasing water injection rates may exceed the fracture gradient and start or extend a fracture. A pressure falloff test conducted on an injection well provides an estimate of the fracture half-length, but the orientation of the fracture cannot be distinguished. A trial and error procedure is shown to determine the fracture orientation and possible affect on the volumetric sweep efficiency on Levelland area waterfloods by using the fracture half-length from a falloff test and a reservoir simulation program.