零井源距VSP数据地层倾角分析和倾角时差校正  

Dip analysis and DMO correction of strata in zero-offset VSP data.

作　　者：王保利[1] 朱光明[2] 

机构地区：[1]西安交通大学 [2]长安大学,陕西西安710054

出　　处：《石油地球物理勘探》2009年第3期282-287,共6页Oil Geophysical Prospecting

摘　　要：在零井源距VSP数据处理中,由于地层倾斜,按双程时校正后的反射波场并不能被拉平,因而使得上行波双程时排齐剖面中的反射波并不能真正排齐,因此走廊叠加就会出现误差,且地层倾角越大,误差越大。本文从零井源距VSP的观测方式入手,分析了地层界面倾角对走廊叠加剖面上反射同相轴位置的准确性和叠加后反射同相轴的频率的影响,推导出了可用于分析地层倾角和进行走廊叠加倾角时差校正的公式。在此基础上提出了一种改进的走廊叠加方法,同时编制了可用于交互分析地层倾角的软件,分别用模型数据和实际资料对所提方法进行了测试处理,证实了方法的有效性。The primary reflection waves recorded in the receiver point with same depth are not double times of first arrivals at the point because of layer dipping in zero-offset VSP data processing, making the reflection waves on upgoing wave two-way time aligned sections be not truly aligned and corridor stack appear errors. The larger the layer dip, the larger the errors. Starting from the surveying pattern of zero-offset VSP, the paper analyzed the influence of dip of bed interface on the correctness of reflection event position on corridor stack section and frequency of poststack reflection event and analyzed the formula used for analyzing layer dip and DMO correction of corridor stack. On that basis, the paper presented an improved corridor stack method and wrote software used for interactive analysis of layer dip at the same time, which is tested and processed by model data and practical data respectively and proved the effectiveness of the method.

关 键 词：零井源距VSP 走廊叠加 地层倾角 倾角时差校正 倾角分析 

分 类 号：P631.443[天文地球—地质矿产勘探] P631.44[天文地球—地质学]