Imaging hydraulic fracture zones from surface passive microseismic data

Vladimir A. Kochnev, Ilya V. Goz, Vitaly S. Polyakov, Issa S. Murtayev, Vladimir G. Savin, Boris K. Zommer, and Ilya V. Bryksin provide some Russian examples of passive microseismic applications for imaging hydraulic fracture zones. Most of the current microseismic methods for hydraulic fracture imaging employ multi-level receiver systems deployed on a wireline array in one or more offset wellbores. A high frequency range (over 100 Hz) of receivers is required (Rutledge et al., 2003, Li et al., 1998, Block et al., 1994, Meadows et al., 1994). Locations of microseisms are calculated from the direction of arrived elastic waves and delays of S-waves from corresponding P-waves. To determine the direction of arrival of separate waves is not a trivial task, further complicated by a large numbers of microseismic events (microearthquakes). For robustness, multiple receiver locations are necessary.