Title

Study on seismic rock physics computational method for shale reservoir

单位

(1.中国石油化工股份有限公司石油勘探开发研究院,北京100083;2.中国石油化工股份有限公司页岩油气勘探开发重点实验室,北京100083;3.国家能源页岩油研发中心,北京100083;4.中国科学院地质与地球物理研究所,北京100029)

Organization

(1.Petroleum Exploration and Production Research Institute,SINOPEC,Beijing 100083,China;2.Sinopec Key Laboratory of Shale Oil/Gas Exploration and Production Technology，Beijing 100083,China;3.National Energy Research & Development Center of Shale Oil，Beijing 100083，China;4.Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China)

摘要

研究通过数值计算地震波场特征直接获得地震波长尺度岩石物理参数及其响应特征的计算岩石物理方法。基于岩心资料,从页岩沉积的随机过程出发,以“层”和“纹层”为基本单元,构建厘米—毫米(cm—mm)级页岩小尺度数值地质模型,并随机加入有机质、有机孔、层间缝、垂直缝和基质孔隙。在小尺度网格应用宏观岩石物理等效介质模型,充分考虑介质的非均匀性,将小尺度地质模型转化为地球物理参数模型。基于小尺度地质模型与小网格地球物理参数模型,进行不同角度平面非均匀地震波传播模拟,提取传播时差,直接计算得到地震波长尺度的岩石物理参数。以胜利油田罗家地区页岩油层为例,改变TOC含量、层与纹层不同厚度和组合、裂隙分布,分别计算弹性参数,并甄选敏感弹性参数,验证了方法的有效性。

Abstract

A new scheme for shale rock physics study is presented.Firstly,Small-scale shale geological model is computed by considering layer,fine-layer,TOC,crack and porosity.Then,Geophysical properties are computed on non-uniform small grids by effective medium theory with heterogeneity being considered.Finally,seismic modeling is utilized to compute seismic elastic parameters by traveltime difference based on the small-scale geological model and the small grid geophysical parameters model.The methods are applied to shale oil area in Shengli Oilfield and seismic responses are variation of TOC and crack density.The results demonstrate the effectiveness of the proposed method,which have the similar trends with lab data and theoretical data by cross plot for variation of TOC and crack density with elastic parameters,especially with anisotropic parameters.

关键词：

小尺度地质建模; 等效介质理论; 格子法地震波场模拟; 计算岩石物理;

Keywords:

small-scale geological modeling,; effective medium theory,; grid method seismic modeling,; computational rock physics;

基金项目

国家重点基础研究发展计划(973计划)项目(2014CB239104和2012CB214806)资助。

DOI

10.3969/j.issn.1000-1441.2016.01.002

页岩油气层地震岩石物理计算方法研究