各向异性叠前偏移技术及应用

Technique and Application of Anisotropic Prestack Migration

以塔里木盆地碳酸盐岩实际地震资料为例,论述了各向异性叠前偏移技术、各向异性参数的求取方法以及各向异性偏移的处理流程。应用效果证实,相对保幅的各向异性叠前偏移技术,通过求取更为准确的各向异性速度和保留丰富的远偏移距振幅信息,提高了偏移速度和偏移算子的精度,有效提高了塔里木盆地碳酸盐岩地震成像品质,使"串珠"反射特征更清楚,断层和断点刻画更加清晰,从而提高地震储集层描述的精度。

The carbonate rocks in Tarim basin are of the obvious anisotropy.Using the conventional isotropic migration method may not only result in error of imaging position,but also affect the quality of seismic imaging,the precision of time-depth transformation and AVO analysis,etc.Taking the actual seismic data of carbonate rocks in Tarim basin as an example,this paper mainly discussed the anisotropic prestack migration technique,the method for evaluating anisotropic parameters and the processing flow of anisotropic prestack migration.The more accurate anisotropic velocity and the preserved abundant far-offset trace information allowed the precision of migration velocity and migration operator to be improved by evaluating the more accurate migration velocity field and reserving far-offset trace information.At the same time,the seismic imaging quality of the carbonate rocks can be effectively increased,and the ＂bead＂ reflectance,the faults and the break points appeared more clearly,thus providing a better gather for AVO inversion and the precision of reservoir description.