Comparative Study on Applicability of Prestack AVO Inversion and Prestack Elastic Parameter Inversion for Reservoir Prediction

Abstract

Prestack AVO inversion and prestack elastic parameter inversion are the common technical methods for reservoir prediction. Finding the direction to improve the reliability of inversion results and selecting the appropriate inversion method are the key points of prognosis of reservoir. Based on the basic data of shale reservoir in Zigui area, such as logging P-wave, S-wave, density, seismic prestack gathers, this study aims to analyze the influence of prestack gathers on inversion results and the applicability of different inversion methods by comparing the two reservoir inversion results. The results show that: (1) For the gas-bearing reservoir interface with less obvious AVO characteristics, the gather angle range (the maximum offset range of seismic acquisition) is of great significance for identifying AVO response characteristics; (2) In the case of general prestack gathers quality, prestack AVO inversion results can only preliminarily indicate the reservoir distribution range, and prestack elastic parameter inversion quantitative research takes gas logging interpretation results as samples, which can clarify its more precise gas-bearing distribution characteristics; (3) It is necessary to optimize prestack gathers to improve the reliability of inversion results.