基于双重孔隙结构的煤层气储层震波速度预测研究  

Study on prediction on seismic wave velocity in coalbed methane reservoir based on dual pore structure

作　　者：唐志远 杨延强 刘国昌[2] TANG Zhiyuan;YANG Yanqiang;LIU Guochang(School of Information and Engineering,Hebet GEO University,Shifiazhuang 050031,China;School of Geophysics and Information Engineering,China Untversity of Petroleum-Beijing,Beijing 102249,China;School of Mathematics and Physics,Hebei GEO University,Shijiazhuaag 050031,China)

机构地区：[1]河北地质大学信息工程学院,河北石家庄050031 [2]中国石油大学(北京)地球物理与信息工程学院,北京102249 [3]河北地质大学数理学院,河北石家庄050031

出　　处：《煤炭科学技术》2018年第12期187-191,共5页Coal Science and Technology

基　　金：国家自然科学基金资助项目(41404099);河北地质大学博士科研启动基金资助项目(BQ2017036)

摘　　要：为了解决煤层气储层具有吸附赋存和裂缝发育特征导致的煤层气储层地震波速度预测较困难的问题,在对煤层气储层基础和速度影响详细分析基础上,结合储层双重孔隙结构、胀缩效应,考虑煤层饱和含气时,气体主要吸附于微孔隙中,大孔隙主要储集水,将煤层气当成基质矿物以求取煤层气的平均弹性模量和平均密度代替干岩石模量和密度,用Gassmann方程进行流体替代,建立了一种煤层气储层震波速度预测方法。经岩心数据推算结果表明,该方法能够提高煤层气储层速度预测准确性,煤层气储层气体含量差异能够引起地震波速度较大变化,从而导致地震资料的响应差异。In order to solve the difficult prediction of the seismic wave velocity in the coal reservoir caused by the adsorption occurrence and the crack development features of the coal reservoir based on the detail analysis on the coalbed methane base and the velocity influences,in combination with the dual pore structure and the expansion and shrink effect in consideration of the saturation gas,the gas was mainly adsorbed in the micro pores and the large pores would mainly store water. The coalbed methane was taken as the matrix minerals in order to have the average elastic modulus and the average density of the coalbed methane to replace the rock modulus and density,a Gassmann Equation was applied to the fluid replacement. Thus a prediction methane of the seismic wave velocity in the coalbed methane reservoir was established. The calculation results of the core data showed that the method could improve the prediction accuracy of the velocity in the coalbed methane reservoir. The gas difference of the coalbed methane reservoir could cause a high variation of the seismic wave velocity and thus could cause the response difference of the seismic information.

关 键 词：煤层气 双重孔隙结构 胀缩效应 GASSMANN方程 速度预测 

分 类 号：TE122.1[石油与天然气工程—油气勘探]