In order to identify and predict the space distribution of fracturesets and karst caves in carbonate layers, a seismic forward modeling algorithm and a prediction method are presented in this paper. The seismic modeling algorithm includes in two key steps in which one is for calculating effective elastic parameters in a fractured and caved media by using elastic wave equation, the other is for wave extrapolating by using acoustic oneway wave equation based on an equivalent geology model consisting of those effective parameters.
Examples of numerical simulation data and real seismic data show that by combining and correlating the seismic forward modeling section with seismic migration section it is possible to identify and predict the fracturecave zone in carbonate rock layers.