Application of Facial Controlled Seismic Inversion in Predicting Heterogeneous Carbonate Reservoir

Fault controlled carbonate reservoir is a new type of oil and gas reservoir put forward in the practice of oil and gas exploration in Tarim Basin in the past 20 years. The reservoir space is mainly composed of various scale faults and fractures formed by fault activity, as well as various caves and pores formed by fluid flow, corrosion and expansion along the faults, with strong spatial heterogeneity. The fault controlled reservoir is very complex in both external morphology and internal structure, but most of it exhibits beaded reflection characteristics in seismic. How to achieve precise reservoir description has always been an urgent scientific research and production problem to be solved. This article proposes a method for facies controlled seismic inversion, which utilizes the predicted results of faults and fractures, as well as conventional inversion results of cave and pore reservoirs, to establish a fault controlled carbonate reservoir facies model. Based on this, inversion is carried out to achieve the goal of integrated prediction of faults and reservoirs. Compared to conventional facies controlled inversion, this method improves the reservoir model and can more comprehensively reflect the structural characteristics of fault controlled carbonate reservoirs, resulting in clearer fault reservoir relationships in the inversion results. This method was tried in Tazhong area of Tarim basin, and 28 wells were used for evaluation. The coincidence rate of reservoir prediction reached 89.3%.