复杂介质最小二乘叠前深度偏移成像方法

The least square pre-stack depth migration on complex media

随着勘探开发的逐步深入,成像精度要求也越来越高,许多高精度偏移成像方法应运而生.本文推导并实现了最小二乘偏移(LSM)方法的理论及算法,通过对SEG-EAGE盐丘模型的偏移试算,证实了LSM方法对复杂构造模型具有较好的适应性和较高的成像精度.通过对LSM成像结果与傅立叶有限差分(FFD)方法和带误差补偿的频率-空间域有限差分(XWFD)方法及高阶广义屏(GSP)方法成像结果对比表明:LSM方法对复杂模型具有较好的适应性,尤其对中深部储层成像精度有了一定的提高.

As the development of the exploratory, more and more complexity for the background setting of the exploratory area, as well as the image resolution. As a result, many high resolution image methods arise like mushrooms after rain. In this paper, we deduced the theory of Least Square Migration （LSM） method, and then, we test our LSM method via the SEG-EAGE salt velocity model. The image result suggests that the LSM has a good adaptability and high image resolution for the complex media. At the same time, the comparison image result of our method and other traditional image methods, such as Fourier Finite Difference （FFD） migration method, XWFD pre-stack migration with error compensation and the General Screen Method （GSM） shows that LSM method has a better adaptive for the complex media, especially for the deeper part of the model.