多波时移地震AVO反演研究

A study on multiple time-lapse seismic AVO inversion

数值模拟了油藏含油饱和度与有效压力变化时移地震AVO的响应,确定利用时移地震AVO区分油藏参数的变化、实现油藏定量解释的可行性.从Aki等AVO近似方程出发,详细推导了P_P波和P_S转换波时移地震AVO计算公式.结合岩石物理近似关系和本文推导的时移地震AVO计算公式,推导了利用多波时移地震AVO反演油藏含油饱和度和压力变化的方程.数据试验表明,文中推导的多波时移地震AVO方程能较好地反演油藏含油饱和度变化和有效压力变化,实现油藏定量解释.

The seismic responses caused by different reservoir parameter variations are numerically simulated, and then the feasibility of discriminating different reservoir parameters and realizing quantitative interpretation using the time_lapse seismic AVO technique is determined. Based on Aki and Richards' simplified AVO equation, the formula of P_P wave and P_S wave for time_lapse seismic AVO is derived in detail. According to the rock physical model and the formula acquired, the multiple time_lapse seismic AVO inversion equations are achieved to discriminate the changes of oil saturation and effective pressure. The simulated data experiment shows that the time_lapse seismic AVO inversion is feasible, and the formula derived in this paper is effective to discriminate changes of oil saturation and effective pressure, and to improve the precision of time-lapse seismic interpretation.