Locating Small Aftershocks Using a Small-Aperture Temporary Seismic Array |
| |
Authors: | Hongyi Li Lupei Zhu |
| |
Institution: | (1) Key Laboratory of Geo-detection, Ministry of Education, China University of Geosciences, Beijing, 100083, China;(2) School of Geophysics and Information Technology, China University of Geosciences, Beijing, 100083, China;(3) Department of Earth and Atmospheric Sciences, Saint Louis University, St Louis, MO 63108, USA |
| |
Abstract: | In this paper, we developed a specialized method to locate small aftershocks using a small-aperture temporary seismic array.
The array location technique uses the first P arrival times to determine the horizontal slowness vector of the incoming P wave, then combines it with S–P times to determine the event location. In order to reduce the influence of lateral velocity variation on the location determinations,
we generated slowness corrections using events well-located by the permanent broadband network as calibration events, then
we applied the corrections to the estimated slownesses. Applications of slowness corrections significantly improved event
locations. This method can be a useful tool to locate events recorded by temporary fault-zone arrays in the near field but
unlocated by the regional permanent seismic network. As a test, we first applied this method to 64 well-located aftershocks
of the 1992 Landers, California, earthquake, recorded by both the Caltech/USGS Southern California Seismic Network and a small-aperture,
temporary seismic array. The average horizontal and vertical separations between our locations and the well-determined catalogue
locations are 1.35 and 1.75 km, respectively. We then applied this method to 132 unlocated aftershocks recorded only by the
temporary seismic array. The locations show a clear tendency to follow the surface traces of the mainshock rupture. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|