1-D VELOCITY MODEL FOR SYRIA FROM LOCAL EARTHQUAKE DATA AND NEW SEISMICITY MAP
IN SYRIA
Authors: Rami Ibrahim, Hiroshi Takenaka, Mohamad Daoud and Tatsuhiko Hara
We performed inversion of P and S wave arrival time
data from a set of 542 events recorded by the Syrian National Seismological
Network during 1995-2004 to determine 1-D velocity structure beneath Syria. We
determined both P and S wave velocity structures with a set of station
corrections. The P wave velocity in the shallow part in the new model is faster
than the current model, while the P wave velocity in the lower part of crust in
the new model is slower than that in the current model. We performed hypocenter
determination using this new velocity model and compared the relocated
hypocenters to hypocenters determined for the current crustal model used by National
Earthquake Center of Syria. There is a significant difference in the
distributions of their focal depths. When the new velocity model is used, the
number of the events in the depth range between 0 and 5 km increases, while
that in the depth range between 10 and 15 km decreases.
The RMSs of the arrival time residuals obtained by the new model are significantly
smaller than those obtained by the current model, which suggests that it is
possible to improve the accuracy of hypocenter determination using this new velocity
model. We find qualitative correlations between the obtained station
corrections and surface geology.
| Citation: | Rami Ibrahim, Hiroshi Takenaka, Mohamad Daoud and Tatsuhiko Hara (2012). 1-D VELOCITY MODEL FOR SYRIA FROM LOCAL EARTHQUAKE DATA AND NEW SEISMICITY MAP IN SYRIA. Bulletin of IISEE, 46, 121-137. |