Velocity inversion and velocity model of complex structures in layer heterogeneous media

Abstract

In conventional velocity inversion, we assume that the reflector is continuous and the medium homogeneous. To meet the requirements for velocity inversion and modeling in a complex area, we present in this paper a velocity inversion method which can be suitable for any arbitrary structural model in heterogeneous media. The method first partitions a subsurface geologic body into a number of velocity blocks according to the exhibition characteristics of interpreted horizons and faults in the time domain, then it derives a local initial interval velocity model by inversing and modeling the selected single‐point velocity, as well as converting the horizons from the time domain to the depth domain so as to form an accurate velocity model by ray depth migration. The inversion and modeling are conducted in a top‐bottom and interactive manner. The theoretical model and real data show that the method improves the accuracy of the velocity model in complex structural areas.