Locate Microseismicity by Seismic Interferometry

We present a new seismic interferometry method to locate microseismicity by crosscorrelating the direct P- and S-waves from repeating sources, e.g., hydro-fracture. Typically microseismic data by surface array are below signal-to-noise ratio for a migration-type approach, and barely pickable for a traveltime-base approach. The repeating sources inside a resolution zone give high signal-to-noise ratio arrivals after stacking in a virtual source gather. This gives us superiority over traditional microseismic processing to remove noises, reflections and surface waves in the virtual source gather. Knowledge of the source excitation time is not needed and more reliability is provided. Numerical tests on an elastic model and noisy field microseismic surface array data partly demonstrate its superiority over the traditional microseismic processing.