Pressure interference data between fractured wells in tight formations during hydraulic fracturing (fracing) has been shown to reflect the geometry of propagating fractures. Interpretation of such data can be used to estimate fracture parameters such as azimuth, length, width and height of the fracture. This pressure interference is ascribed to the poroelastic impact of the propagating fracture’s stress shadow. Numerical modeling of this observation using fully-coupled geomechanical simulators has been shown to capture field observations. Numerical modeling, however, can be time consuming and not feasible for application to on-the-fly solutions during the frac treatment. There is a need for fast simple models or simulation tools that can provide a very quick, near real-time interpretations of the position and geometry of the propagating fractures. In this work, we present a new analytical model that provides a quick method of fracture diagnostics during a frac treatment.

This new analytical model uses the fundamental stress shadow equations for simple fracture geometries and computes the impact of fracture opening on the pressure response at pressure gauge locations in surrounding wells. The model captures critical characteristics observed in field pressure interference observations. For example, the model predicts the downward slope of the observed pressure data and associates it with the region of lower compression ahead of the propagating fracture. A reduction in the observed pressure response with increasing distance from the observation well is also observed. Such predictions allow us to quickly and quantitatively interpret pressure interference data in terms of estimates of fracture location, orientation and geometry so that changes to a fracture pumping schedule can be made in near real-time.