川东北地区地层条件下致密储层力学性质实验分析  

THE EXPERIMENTAL ANALYSIS OF MECHANICAL PROPERTIES OF COMPACT REVERIVOR ROCKS UNDER FORMATION CONDITIONS,NORTHEAST OF SICHUAN BASIN,CHINA

作　　者：李智武[1] 罗玉宏[2] 刘树根[1] 龚昌明[2] 单钰铭[1] 刘维国[1] 刘顺[1] 雍自权[1] 孙玮[1] 

机构地区：[1]成都理工大学"油气藏地质及开发工程"国家重点实验室,四川成都610059 [2]中国石油西南油气田分公司川中油气矿,四川遂宁629000

出　　处：《矿物岩石》2005年第4期52-60,共9页Mineralogy and Petrology

摘　　要：利用“MTS岩石物理参数测试系统”对四川盆地东北部埋藏深度3200m～4200m的上三叠统须六段以及中侏罗统凉高山组和沙一段储层垂直和平行层理方向的岩石样品进行了模拟地层条件(包括围压、孔压、温度、孔隙饱和介质等)下的力学性质测试。实验结果显示,所有样品都表现为脆性特征,破坏前轴向总应变均小于2%。须六段、凉高山组和沙一段的抗压强度均值分别为394.2MPa,173.5MPa和524.6MPa;杨氏模量均值分别为57.0GPa,35.6GPa和53.7GPa;泊松比均值分别为0.219,0.275和0.208。岩石组成和结构是决定岩石力学性质的内在因素,随着岩石中泥质含量和孔隙度的降低,以及石英类碎屑含量的增加,岩石抗压强度和杨氏模量均增加,而泊松比的变化较为复杂;当岩样中含有先存薄弱面时,其抗压强度和杨氏模量明显降低。多数情况下,平行层理方向样品的抗压强度和杨氏模量大于垂直层理方向,而泊松比则刚好相反。孔隙水对岩石力学性质具有显著影响,饱水样品的泊松比明显大于干燥样品。The mechanical properties of reservoir rocks are important basic data for oil and gas exploration and exploitation. This paper presents the mechanical parameters （including compressive strength,Young＇s modulus and Poisson＇s ratio） and stress-strain curves measured under simulated formation conditions （including temperature, pore pressure ,confining pressure ,dry or saturated by water,and different directions of samples） of compact reservoir rocks of Xujiahe Formation, Triassic, and Lianggaoshan Formation and Shaximiao Formation, Juriassic, northeast of Sichuan Basin. A variety of rocks, including sandstone, siltstone and mudstone, with current depths of burial ranging from 3 200 m to 4 200 m,are tested using “Rock Physical Parameter Automatic Testing System” maded by MTS Corporation. Results of tests on rock mechanical properties under formation conditions and analysis of factors influenced them are summarized as follows：1） All samples show brittle failure under formation condition,and their total axial pre-failure strains are less than 20/4o with three types of stress-strain curves of elastic,elastic-plastic,and plastic-elastic. 2） The average compressive strengths of rock samples under formation condition are 394.2 MPa, 173.5 MPa,and 524.6 MPa,respectively for Section VI of Xujiahe Formation, Lianggaoshan Formation and Section I of Shaximiao Formation; average Young＇s moduli are 57.0 GPa,35.6 GPa and 53.7 GPa; and average Poisson＇s ratios are 0. 219,0. 275 and 0. 208. 3） The composition and structure of rock are the inherent factors determining the mechanical properties of rock. With the increases in clay content and porosity,the compressive strength and Young＇ s modulus decrease,while the Poisson＇s ratios increase for the former and decrease for the latter, especially when saturated by water. With the increase in siliceous clasts in rock,the compressive strength and Young＇s modulus increase,while the Poissonrs ratio show only slight increases or no changes. When sample contain

关 键 词：地层条件 储层 岩石力学性质 抗压强度 杨氏模量 泊松比 

分 类 号：P618.130.21[天文地球—矿床学]