叠前时间偏移在华北地区的应用

Application of Prestack Time Migration in North China Area

从应用的角度较详细地论述了三维叠前克希霍夫时间偏移的过程。在给定合理的偏移孔径下,三维叠前克希霍夫时间偏移利用均方根速度对叠前地震数据进行逐道处理,从而得到准确的归位数据。叠前时间偏移相对叠后时间偏移而言,前者能够进一步提高地下信息的成像质量及归位准确性,信噪比和分辨率也得到了改善,能够满足精细的地震资料的解释。因此,三维叠前克希霍夫时间偏移对于速度变化平缓、地下构造较复杂的地区具有广泛的应用价值。

The authors illustrated in detail the process of 3D prestack Kirchhoff time migration from the point of application.With the improvement of accuracy of field sesmic exploration,the demand on the seismic data processing is more strict.Within a user-controlled aperture,3D prestack Kirchhoff time migration uses the field of root-mean-square velocity to process the sesmic data traces of prestack by trace,thus gets the accurate migration data.Compared to poststack time migration,prestack time migration can further enhance the image quality of subsurface information and the accuracy of migration, also improve signal-to-noise ratio and resolution.All these are necessary to the detailed interpretation of sesmic data.Therefore,3D prestack Kirchhoff time migration is widely applicable to the areas where there is no big variation in velocity and where there are complicated subsurface structures.