In areas with complex geological condition near surface, traveltime tomography is not able image near surface model accurately, so that used joint seismic gravity inversion method. This method combines traveltime tomography and gravity inversion. Velocity model from joint seismic gravity inversion had better resolution than velocity model from traveltime tomography. It can be seen from reflector continuity at PSTM section with joint seismic gravity inversion is better than the traveltime tomography.
