宽/窄方位三维观测系统对地震成像的影响分析——基于地震物理模拟的采集方法研究  

Analysis of influence of 3-D wide/narrow geometry on seismic imaging (1): Acquisition study based on seismic physical simulation

作　　者：狄帮让[1] 孙作兴[2] 顾培成[2] 魏建新[2] 徐秀仓[2] 

机构地区：[1]北京市昌平区中国石油大学资源与信息学院CNPC物探重点实验室,北京102249 [2]中国石油大学CNPC物探重点实验室

出　　处：《石油地球物理勘探》2007年第1期1-6,共6页Oil Geophysical Prospecting

基　　金：中国石油天然气集团公司基础性研究项目(06A10102)。

摘　　要：“在复杂地区采用宽方位还是窄方位观测问题”,成为近十年中三维地震方法研究的一个热点问题。考虑到该问题的复杂性,本文结合中国东部滩海地区的地质特点,选择了一个水退模式扇形薄砂体构建地质模型,设计了16线4炮全方位和6线4炮窄方位两个观测系统,对扇体进行了地震物理模拟分析。通过对三维偏移数据体时间切片的宏观全局分析和偏移剖面的微观局部分析,得出如下认识:在上覆地层相对平缓、速度横向变化不大的地质背景下,通过采用CMP叠加偏移处理,宽方位和窄方位三维采集都能对地下目标实现基本正确的地震成像,且两者的成像分辨率基本相当。The issue of wide-azimuth survey or narrow-azimuth survey in complex area has become a hot spot issue in study of 3-D seismic approaches in recent 10 years. Considering the complexity of the issue and in combination with the geologic feature of beach area in eastern China, the paper selects offlap-based thin fan sand body to construct the geologic model and designs two patterns of geometry: 16L4S full azimuth and 6L4S narrow azimuth to analyze the seismic physical simulation. It yielded following knowledge by macroscopic global analysis of 3-D migrated data volume and microscopic local analysis of migrated sections,under the geologic conditions of relative smooth overburdens and less-changed lateral velocities, the 3-D wide and narrow azimuths acquisition can basically obtain correct seismic imaging of underground targets by using CMP stack migration processing and both imaging resolution is basically equivalent.

关 键 词：宽方位角 窄方位角 三维观测系统 地震分辨率 地震物理模拟 

分 类 号：TE19[石油与天然气工程—油气勘探]