Picking and Epicenter Locating Program Based on Waveform Cross- Correlation and Its Application for Processing Seismic Data in New Mexico

It is widely observed that seismic sources occurring very close to each other can share very similar waveforms. Using this property, an adaptive, automatic phase-picking and epicenter-locating program based on waveform cross-correlation has been developed and applied to process daily seismic data of New Mexico. The core of this program is a reference seismic event database, from which the phase and location information of a new event can be inferred. With a sufficiently complete reference seismic dataset, this program should produce robust initial seismic phase estimates while greatly improving the handling of false triggers due to telemetry or other transient noise. These automatic results are designed to be as precise as the manually processed results. 160 well-picked earthquakes and mining explosions in New Mexico during 1997-2003 were collected as an initial reference event set covering most of the historically active source regions in the state. Each waveform in the reference event set has a high signal-to-noise ratio and accurately-picked P and S phases. Two methods were developed to automatically calculate waveform cross-correlation phase-picking and the location of epicenter. The first, waveform-pair cross-correlation matching method correlates the most similar waveform from the reference dataset to each waveform of a new event station by station and