oa The 3D SEG Salt Model - Dreams and Reality

Wave-equation modeling of 3-D seismic data in non-trivial geologic models is a non-trivial computational problem. While ray-tracing and other simple methods offer advantages in speed and/or simplicity, we are drawn toward using as complete a physical description of wave phenomena as we can aspire to. Typically this means full wave equation finite-difference or finite-element methods. If we are interested in P-wave or "acoustic" data, we have the choice of modeling a zero-offset section directly, or modeling shot records which would simulate a typical field experiment; one can also model other experiments, hypothetical or real, such as plane wave or conical wave sources. From the point of view ofthe numerical simulation, the goal is to get as many wavelengths of some specified frequency into the computational model as possible.