FDM computation of seismic wavefield for an axisymmetric earth with a moment tensor point source
© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2006
Received: 28 April 2006
Accepted: 4 July 2006
Published: 15 September 2006
Axisymmetric modeling has been playing an important role in global seismic waveform modeling since it can correctly model geometrical spreading effects in 3-D within computational resources comparable to 2-D modeling. However, in the previous investigations on axisymmetric modeling, seismic sources were restricted to axisymmetric sources such as an explosive source. In this paper, we propose implementation of an arbitrary moment tensor point source to axisymmetric modeling using the finite-difference method (FDM). The validity and efficiency of this technique are demonstrated by comparing synthetic seismograms with analytical solutions for a homogeneous earth model, as well as with the DSM synthetics for a spherically symmetric earth. We also show a numerical example with a subducting slab structure.