Deformation Characteristics of Low Permeability Rocks under Confining Pressure
In the study of percolation mechanics of deformable media,permeability modulus is used bymany researchers to take stress sensitivity into account．Permeability modulus is defined followinglinear poroelastic theory,thus permeability varies exponentially with pressure．However,for lowperrneability and tight reservoir rocks,the hypothesis of linear poroelastic deformation dose not fit wellwith experimental data. In this Paper,CMS300,rock mechanics measurement system,mercury iniectionmethod and cast thin section identification are used to study the deformation characteristics of lowpermeability and tight reservoir rocks．Experimental data show that the deformation process is formslightly plastic deformation to elastic deformation．and to plastic deformation. The slightly plasticdeformation at the lnitial stage of effective stress increase is the major reason which causes dramaticpermeability reduction,namely,strong stress sensitivity. This deformation characteristic is relative tohigh content of clay and cement,and narrow pore throat．Base on experimental results,a new stresssensitive coefficient is defined to express the relationship of permeability and effective stress,which fitswell wlth experimental data．By this method,routine core data could be conveniently convened intoin-situ condition．
low permeability rock confining pressure deformation characteristics stress sensitivity
LUO Ruilan FENG Jinde
Research Institute of Petroleum Exploration&Development-Langfang, China National Petroleum Corporati Research Institute of Petroleum Exploration&Development, China National Petroleum Corporation, Beiji
国际会议
2009 International Forum on Porous Flow and Applications(第十届全国渗流力学学术会议)
武汉
英文
21-26
2009-04-26（万方平台首次上网日期，不代表论文的发表时间）