We examined over the Israel Seismic Network (ISN) the seismogram envelopes vs. group velocity V = R/T, where R is the epicenter distance and T the travel time, and found out a persistent difference between quarry blasts and earthquakes. The data include 53 seismic events occurring in northern Israel with magnitudes of M(L) = 1.0-2.6 and at distances of 15-310 km. Within the 1-4 km/s range we measured the velocity v(ms) at which the envelope reaches its maximum for each ISN station. A simple linear discrimination function c = b + 0.33 a, based on an empirical relationship between the V(ms) and R: V(ms) = a + b In(R) provides effective separation between the regional earthquakes and explosions. These results are attributed to different excitation of regional surface waves from these two types of seismic events.
Bibliographical noteFunding Information:
This study was sponsored by the US DOE and monitored by the Air Force Phillips Laboratory under Contract Number F19628-95-K-0006 and partially by the US Department of Defense, Contract Number DSWA01-97-C-0151 and by the German Israel Foundation for Scientific Research and Development, Contract No.: G 0463-245.08/95.
- Group velocities
- Israel Seismic Network
- Seismic phases
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Physics and Astronomy (miscellaneous)
- Space and Planetary Science