摘要：Shale gas reservoirs contain a large number of natural fractures. When shear slip occurs during hydraulic fracturing, it will increase reservoir permeability and improve the reservoir stimulation performance. Because shale contains a large amount of clay and organic matter, its shear slip behavior differs from that of other rocks. In this study, the shear behavior of different shale blocks is experimentally studied, and the proportion of clay and organic matter in the shale dominates the shear slip behavior. Specifically, the friction coefficient and shear strength decrease with the increasing content of clay and organic matter. A microscopic support model was developed to describe the different shear slip behaviors for different contents of clay and organic matter. When the clay and organic matter content is lower than a critical threshold (35%), shale is microscopically grain supported and brittle shear occurs and the material is prone to shear dilation. When this content is greater than a critical content (43%), the microscopic structure is a matrix-supported fabric and plastic shear occurs, which is prone to shear contraction. Shale with contents between these two critical thresholds has a mixed-support fabric, which is a transition type between brittle and plastic shear. If the proportion of clay and organic matter is less than 35%, the natural fracture tends to dilate and retain a certain degree of opening after shearing, improving stimulation performance. When the proportion is more than 43%, shear contraction occurs on the natural fracture surface, which is not conductive and cannot increase reservoir permeability.

关键字：shale clay and TOC friction coefficient shear dilation packing model

ISSN号：2169-9313

卷、期、页：卷: 124 期: 9 页: 9505-9525

发表日期：2019-09-01

期刊分区（SCI为中科院分区）：二区

收录情况：SCI（科学引文索引印刷版）,ESI（基本科学指标数据库）,SCIE（科学引文索引网络版）

发表期刊名称：JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH

参与作者：Meng, Fanbao

通讯作者：王剑波,刘桐源,张衍君

第一作者：葛洪魁,王小琼,申颍浩

论文类型：期刊论文

论文概要：王剑波,葛洪魁,王小琼,申颍浩,刘桐源,张衍君,Meng, Fanbao，Effect of Clay and Organic Matter Content on the Shear Slip Properties of Shale，JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH，2019，卷: 124 期: 9 页: 9505-9525

论文题目：Effect of Clay and Organic Matter Content on the Shear Slip Properties of Shale