碳酸盐岩裂缝型储层最小二乘偏移成像方法研究

碳酸盐岩裂缝型储层是海相油气储层以及西部探区的重要储层类型之一,多表现为缝洞储集体形态,埋藏深度大,地震反射波信号复杂,波场特征分析困难,因而对其进行高分辨成像具有一定的难度.本文推导并实现了基于最小二乘理论的偏移成像(LSM)方法,并将LSM用于西部探区碳酸盐岩裂缝型储层等效地震地质模型的偏移成像工作,成像结果表明:在理论上,LSM方法能够较好地分辨出埋藏深度在3000 m以下的中深部20 m尺度碳酸盐岩裂缝型储层,在西部碳酸盐岩裂缝型储集体地震勘探中,具有较好的适应性.

A study of least-squares migration imaging method for fractured-type carbonate reservoir

As an important type of marine oil-gas reservoirs, especially in western exploration area, fractured carbonate reservoir often has many special features, including a fracture-cave formation, a deep buried depth, complex reflection wave components and difficult analysis of its wave field characteristics. Due to such features, it is difficult to image fractured-type carbonate reservoir with high-resolution. In this paper, the basic theory of least-squares migration (LSM) is deduced and then we implemented this migration approach. The imaging results of equivalent seismo-geological models of fractured carbonate reservoir have showed that LSM had a good resolution on 20-meter scale fractured carbonate reservoir with a depth of more than 3000 meters, and it is well adaptable when used to prospect fractured-type carbonate reservoir in the western exploration area.