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Passive seismic source location using group sparsity constrained two-way waveform inversion

Passive seismic source location plays an important role in the seismological community for it is commonly used in retrieving the epicenter of earthquakes and evaluating the effectiveness of hydraulic fracturing. Time reversal imaging is one of the most popular methods for source imaging. This method back-propagates seismic recordings into medium and focuses energy at source locations. However, events often can’t be fully focused leading to inadequate resolution of sources from a limited observing aperture. To solve this problem, this paper illustrate a source location method that adopts group sparsity constrained waveform inversion. This method can retrieve source locations and origin time simultaneously and the adopted group sparsity constraint is capable of yielding spatially sparse results while the source function is smooth in time axis .