Locating micro-events in Long Beach, CA urban environment with a dense array
نویسندگان
چکیده
Micro-earthquake activity is reported for the first 6 months of 2011 in Long Beach, CA using a density urban exploration seismic network. Detected events include at least four times as many man-made events as possible real earthquakes indicated by repeated locations, and distinct patterns in the hour-of-day and day-of-week origin times. Some discrimination appears possible utilized the earthquake spectral behavior in the wavelet transform domain. The back-projection of the seismic data onto a prescribed fault plane of the Newport-Inglewood fault produces interesting slip patterns over a time window spanning a small earthquake.
منابع مشابه
Imaging widespread seismicity at midlower crustal depths beneath Long Beach, CA, with a dense seismic array: Evidence for a depth-dependent earthquake size distribution
We use a dense seismic array composed of 5200 vertical geophones to monitor microseismicity in Long Beach, California. Poor signal-to-noise ratio due to anthropogenic activity is mitigated via downward-continuation of the recorded wavefield. The downward-continued data are continuously back projected to search for coherent arrivals from sources beneath the array, which reveals numerous, previou...
متن کاملSupporting Information for ”Imaging widespread seismicity at mid-lower crustal depths beneath Long Beach, CA, with a dense seismic array: Evidence for a depth-dependent earthquake size
We present supporting material for the manuscript ”Imaging widespread seismicity at mid-lower crustal depths beneath Long Beach, CA, with a dense seismic array: Evidence for a depth-dependent earthquake size distribution”. The material contains three figures. The purpose of the figures is to illustrate the advantages of downward-continuing the data prior to back-projection, and to provide detai...
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