川东气田盐岩、膏盐岩蠕变特性试验研究  

Experimental study of creep characteristics of rock gypsum-salt and rock salt in Chuandong gas field

作　　者：李萍[1] 邓金根[1] 孙焱[2] 闫新江[1] 徐显广 

机构地区：[1]中国石油大学(北京)石油工程学院,北京102249 [2]中石化国际石油勘探开发有限公司,北京100083 [3]中国石油集团公司钻井工程技术研究院,北京100097

出　　处：《岩土力学》2012年第2期444-448,共5页Rock and Soil Mechanics

基　　金：国家863项目资助(No.2006AA06A109)

摘　　要：对川东气田盐岩、膏盐岩进行了矿物组分测定,采用TAW-1000深水孔隙压力伺服试验系统进行了蠕变试验,分析了固有的矿物组分及偏应力、温度、围压对蠕变的影响,结合蠕变曲线和岩石参数,提出了稳态蠕变速率本构方程。研究表明:川东气田盐岩、膏盐岩矿物组分以NaCl、CaSO4为主,其中NaCl含量最高可达93%以上;岩石固有的矿物组分是影响岩石蠕变特性的内因,随NaCl含量增加,瞬态蠕变、稳态蠕变速率相应增大;随偏应力、温度的增加稳态蠕变速率增大,围压对其影响不大;通过试验数据拟合得出赫德(Heard)蠕变本构方程中的参数,求出不同偏应力、温度下盐岩、膏盐岩的稳态蠕变速率,为川东气田盐岩、膏盐岩地层安全钻进泥浆密度窗口计算和套管非正常变形分析提供了理论依据。Through analyzing mineral composition of the rock salt and rock gypsum-salt in Chuandong gas field,the creeping test study is carried out with the TAW-1000 deep pore pressure servo test system.The impacts of mineral compassion,deviator stress,temperature and confining pressure on creep have been analyzed.Based on the creep curve and rock parameters obtained by the experiment,steady-state creep rate constitutive equation is proposed.The results show that the main mineral compassion of rock salt and rock gypsum-salt in Chuandong gas filed are sodium chloride and calcium sulfate;the highest percentage of sodium chloride can be as much as 93%,inherent mineral composition is the internal factors of rock creep.The higher sodium chloride content is,the larger transient creep and steady-state creep rate become;the higher deviator stress and temperature are,the larger steady-state creep rate will be,on which the effect of confining pressure is very small.The parameters of Heard creep constitutive equation are obtained by fitting test data;and then the steady-state creep rates of rock salt and rock gypsum-salt under different deviator stresses and temperatures can be acquired.Eventually,it can provide theoretical basis for safe drilling of rock salt and rock gypsum-salt for Chuandong gas field,mud density calculation and abnormal casing deformation.

关 键 词：川东气田 盐岩 膏盐岩 矿物组分 蠕变试验 本构方程 

分 类 号：TE21[石油与天然气工程—油气井工程]