MOMENT TENSOR INVERSION OF NEAR SOURCE SEISMOGRAMS
Authors: Yuji YAGI, Naoki NISHIMURA
We
constructed a program set for estimating moment tensor solutions using near
source seismograms. We take the effect of the
source time function into account, which has been neglected in predominant
program sets of the moment tensor analysis with near source seismograms. In our
program set, we approximate the horizontal location of the centroid to be
epicenter, and then estimate a seismic source duration and depth of centroid in
the moment tensor inversion procedure. To evaluate our program set, we applied
it to three earthquakes: an aftershock (MJMA
6.4) of the 2003 Tokachi-oki great earthquake, the 2004 Nemuro-oki earthquake (MJMA 7.1) and its aftershock
(MJMA 4.2). The results
show that the obtained moment tensor solutions for large earthquakes are consistent with those in other studies. We also found that the neglect of the
source time duration will result in an underestimation of the seismic moment.
Citation: | Yuji YAGI, Naoki NISHIMURA (2011). MOMENT TENSOR INVERSION OF NEAR SOURCE SEISMOGRAMS. Bulletion of IISEE, 45, 133-138. |