中江气田沙溪庙组“暗点”型薄砂岩储层隐蔽机理分析及识别对策  

Concealed mechanism analysis and identification countermeasures of dim-spot thin sandstone reservoirin Shaximiao formation of Zhongjiang gas field

作　　者：陈思远 丁蔚楠[2] 曹俊兴[1] 谭峰[1] CHEN Siyuan;DING Weinan;CAO Junxing;TAN Feng(Key Laboratory of Earth Exploration and Information Technology of Ministry of Education,Chengdu University of Technology,Chengdu 610059,China;Research Institute of Exploration and Development,Exploration and Development Research Institute,Sinopec Southwest Oil and Gas Branch Company,Chengdu 610041,China)

机构地区：[1]成都理工大学地球勘探与信息技术教育部重点实验室,成都610059 [2]中国石化西南油气分公司勘探开发研究院,成都610041

出　　处：《物探化探计算技术》2023年第3期281-288,共8页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(42030812,41974160);中国石化科技部项目(P20055-6)。

摘　　要：砂岩油气储层在地震剖面上一般表现为“亮点”,但钻探发现四川盆地中江气田的一些砂岩储层在地震剖面上表现为“暗点”,不易识别。这里依据钻测井资料,采用地震正演模拟方法分析了这些储层地震响应表现为“暗点”的机制,认为是Ⅱb类AVO(Amplitude variation with offset)响应砂岩在特定厚度的薄层调谐作用下,在叠前道集中发生了极性反转,从而使得原本在叠后剖面上应为较“亮点”的反射变成了“暗点”。针对这种储层隐蔽机制,采用高分辨处理与AVO分析相结合的方法,成功识别出了消隐的河道砂储层,为“暗点”型薄砂岩储层的识别提供了可参考的成功范例。Gas Sandstone reservoirs generally appear as bright spots on seismic profiles.However,drilling has discovered that some sandstones of the Shaximiao Formation in the Zhongjiang Gas Field in the Sichuan Basin are dim spots that are difficult to identify.Based on logging data,the paper uses the seismic forward model to analyze the mechanism of the seismic response of these dim spot reservoirs.It is believed that polarity reversal occurs in the pre-stack gathers for the TypeⅡb sandstone under the influence of thin-bed tuning of a certain thickness,making the bright amplitude on the post-stack profile dark.Aiming at this kind of reservoir,combining high-resolution processing and AVO analysis was used to successfully identify hidden channel sand reservoirs.This provided a successful example for identifying thin dim spot reservoirs.

关 键 词：储层预测 暗点 薄储层 隐蔽砂体 沙溪庙组 

分 类 号：P631.4[天文地球—地质矿产勘探]