A Joint Waveform Inversion Strategy - Combing Full Waveform Inversion with Prismatic Waveform Inversion

Prismatic wave contains a lot of subsurface information that primary can not reach. In this paper, prismatic wave is used alone for imaging in order to improve the inversion speed of high and steep structure. Under the guidance of this idea, a prismatic waveform inversion (PWI) method is proposed. PWI has a significant drawback that an iteration time of PWI is more than twice as that of PWI, and in the meantime it can not use full wave field information, so prismatic waveform inversion is combined with full waveform inversion to propose a joint inversion method. In this method, FWI and PWI are applied alternately in the process of previous iterations, and only FWI is applied in the process of later iterations. Model test suggests that the joint inversion method is relatively less dependence on the initial model with high inversion efficiency and accuracy for the model with steep dip angle structure.