Pickless event detection and location: The Waveform Correlation Event-Detection System (WCEDS) revisited

Arrowsmith, Stephen and Young, Christopher and Ballard, Sanford and Slinkard, Megan and Pankow, Kristine
Bulletin of the Seismological Society of America, 106(5): 2037-2044, 2016

The standard seismic explosion‐monitoring paradigm is based on a sparse, spatially aliased network of stations to monitor either the whole Earth or a region of interest. Under this paradigm, state‐of‐the‐art event‐detection methods are based on seismic phase picks, which are associated at multiple stations and located using 3D Earth models. Here, we revisit a concept for event‐detection that does not require phase picks or 3D models and fuses detection and association into a single algorithm. Our pickless event detector exploits existing catalog and waveform data to build an empirical stack of the full regional seismic wavefield, which is subsequently used to detect and locate events at a network level using correlation techniques. We apply our detector to seismic data from Utah and evaluate our results by comparing them with the earthquake catalog published by the University of Utah Seismograph Stations. The results demonstrate that our pickless detector is a viable alternative technique for detecting events that likely requires less analyst overhead than do the existing methods.