Bill Corley

Interpreting Fracture Length From Multi-array Induction Logs

Summary The azimuth and length are two of the most important parameters concerning a hydraulic fracture. The azimuth is often recognized from a borehole image logs. However, it is difficult to determine the length of a fracture. In this paper, a new method is presented to interpret fracture length from array induction log data. Our new method is based on a simple relation between the net apparent resistance and the fracture length. The new method allows rapid calculation of fracture length from the verticalresolution-matched induction log curves. As an input, the method requires a priori information about the resistivity of the unfractured formation which may be derived from a logging-while-drilling measurement or simply taken as the deepest reading induction log as an initial guess. The method has been tested with field data and yields comparable results to those derived from an inversion method.