Source-Scanning based on Navigated Automatic Phase-Picking (S-SNAP) for Delineating the Spatiotemporal Distribution of Earthquake Sequence in Real Time: Application to the 2019 Ridgecrest, California Sequence

Session: Leveraging Advanced Detection, Association and Source Characterization in Network Seismology
Type: Oral
Date: 4/30/2020
Time: 04:00 PM
Room: 120 + 130
Description: 

Recent improvements in seismic data processing techniques have enhanced our ability to detail the evolution of major earthquake sequences in space and time. One such advance is new scanning algorithms that allow large volumes of waveform data to be analyzed automatically, removing human biases and inefficiencies that may inhibit standardized monitoring efforts. The Seismicity-Scanning based on Navigated Automatic Phase-Picking (S-SNAP) workflow has been demonstrated to be an excellent tool in producing high-quality earthquake catalogs for injection-induced seismicity monitoring. S-SNAP differs from the match filtering algorithm in that it requires no templates and detects earthquakes as individual events, regardless of waveform similarities. In this study, we modify the original S-SNAP workflow to make it capable of delineating the spatiotemporal distribution of major earthquake sequences in real time. We take the July 2019 Ridgecrest, southern California earthquake sequence as an example to demonstrate the advantages of S-SNAP over Seiscomp3, one of the most popular automatic earthquake detection and location software. The final catalog reported by the USGS more than six months after the mainshock event is used as the reference in our comparison. Our results indicate that the S-SNAP catalog reaches comparable completeness and accuracy as the USGS catalog yet requires no human inspection and much less processing time. If S-SNAP is used in routine network operations, it is technically feasible to provide real-time information on aftershock-related hazard assessment during major earthquake sequences.

Presenting Author: Fengzhou Tan

Authors