Method of generating prestack synthetic seismograms of spherical wave

Key words:  spherical wave  prestack synthetic seismogram  reflectivity method  forward modeling

Abstract:

The inversion of prestack seismic data was conducted on the basis of some forward algorithms. The reflectivity method was adopted to compute the prestack synthetic seismograms in layered medium. Formulas for calculating reflection and transmission coefficients of P and S waves in frequency-slowness domain were derived on the assumptions of plane P-wave incidence and full solid medium. Method of generating plane-wave synthetic seismograms in the intercept-time ray-parameter (z~p) domain was developed. Reflectivity function in frequency-slowness domain was transformed to time-space domain by generalized Filon integration method and prestack synthetic seismograms were generated. The solution to critical problem and truncation effect was presented and the quality of record was improved. The modeling of full wave field including the primary reflection, multiple and converted wave was got. The numerical test and real application show that the computation speed and accuracy can be increased by the reflectivity method, and which lays solid foundation for prestack inversion.