三维观测系统参数的退化性处理试验

Degradation processing experiment based on 3-D geometry parameters

（1.西南石油大学，四川成都 610500；2.中国石油天然气集团公司四川石油管理局地球物理勘探公司，四川成都 610213）

Southwest Petroleum University, Chengdu 610500, China

地震观测系统参数对资料处理的结果和解释精度有很大的影响，而往往由于客观条件的限制以及对地下地质特征认识的不足，有些采集参数不能满足资料处理和解释的要求。利用新疆准噶尔盆地的一块高分辨率三维地震资料，进行了面元、炮数和排列长度等采集参数“退化性”处理试验，探讨了由于这些参数的改变对最终叠加剖面产生的影响。通过对试验结果的分析发现：①面元大小的改变会造成覆盖次数降低，影响叠加剖面的信噪比和分辨率；②激发炮数的减少，会造成覆盖次数降低，影响叠加剖面的信噪比，同时由于炮检距的分布发生了变化，使浅层反射信息的接收受到了影响；③排列长度的改变使炮检距发生了变化，对地震反射的能量会造成一定影响，同时还会影响速度分析的精度。

The geometry parameters greatly affect the data processing and interpretation. Unfortunately, being limited by some objective conditions and by the understanding on underground geological characteristics, some acquisition parameters can not satisfy the requirement of data processing and interpretation. By using the 3D high-resolution seismic data from the Junggar basin, the degradation processing experiment of the acquisition parameters such as the bin, the number of shot, and the array length was performed and the effect of these parameters on the final stack profile was discussed. The results show that 1) changing the size of bin will result in a decrease of fold, affecting the signal-to-noise ratio and resolution, 2) reducing the number of shot will also decrease the fold number and affect the signal-to-noise ratio and, at the same time, the receiving of reflection information at shallow layers will be affected because of the change in the distribution of offset, and 3) changing the array length will shift the offset, affecting the reflection amplitude and the accuracy of velocity analysis.