Pre-stack elastic parameter inversion of ray parameters

Abstract

P is a ray parameter. Seismic wave path of P gather spreads nearly along the ray path. Compared with angle gather, P gather can be obtained directly from seismic data and is independent of overlying strata velocity, which avoids the inversion error caused by inaccurate velocity models. Based on P stacked gather, ray elastic impedance of different P values and pre-stack elastic parameters have been computed using Bayesian sparse pulse inversion and constrained search method, respectively. The method has been applied to reservoir prediction of the Yuanba area in the north of Sichuan depression. Exploration results indicated that P stacked data can better delineate the geological body compared with angle stacked data. In addition, stable solutions are easier to be obtained by Bayesian sparse pulse inversion and constrained search method. The pre-stack elastic parameters of P gather showed higher precision and more authenticity than that of angle gather. This methodology has achieved excellent results in reservoir prediction of the Yuanba area and has huge potential for future application in exploration and development.