渐变观测系统的设计原则及其应用

本文根据塔里木盆地孔雀河地区的复杂构造特点，提出了一种渐变观测系统的设计思路——根据工区地质构造变化趋势和日的层埋深变化情况逐点、逐段设计采集参数(最大炮检距、道距、组合基距、覆盖次数等)，其中最大炮检距的选择考虑了动校正拉伸、速度分析精度、有效波和干扰波分离、反射系数稳定、有效压制多次波等因素，所设计的渐变观测系统能满足不同层次物理点位的动校正拉伸、速度分析精度和反射系数的要求。南北向和东西向地震测线采用不同的排列方式。在该区采用渐变观测系统所采集的单炮地震记录品质稳定，信噪比高，浅层多次波、折射波等干扰波减弱，较好地解决了资料处理中的速度分析、动校正拉伸、静校正、叠加及偏移成像问题，取得了明显效果。

Gradually-geometry changed design principle and application.

According to the characteristics of complex structures in Kongquehe area of Tarim basin,the paper presented a designing thought of gradually changed geometry: designing the acquisition parameters ( maximum offset,group interval,geophone separation,folds etc.) point by point and segment by segment according to the trend of geologic structural variation and buried depth of targets,among which the NMO stretching,the accuracy of velocity analysis,separation of useful wave from interference,stable reflectivity and effective multiple suppression etc. are considered in selection of maximum offset,designed gradually changed geometry can meet the needs of NMO stretching,accuracy of velocity analysis and reflectivity at the physical points with different layers.Different spread patterns are used for seismic lines in N S and E W directions separately.Acquired seismic single shot records are characteristics of stable quality,high S/N ratio and reduced shallow multiple and refraction after using designed gradually changed geometry,better solved the problems existed in data processing such as velocity analysis,NMO stretching,static corrections,stack and migration imaging and achieved good effects.