中伊朗盆地地层条件下裂缝性储层岩石力学性质实验分析

EXPERIMENTAL ANALYSIS OF THE ROCK MECHANICAL PROPERTIES OF THE FRACTURED RESERVOIR UNDER FORMATION CONDITIONS IN THE CENTRAL IRAN BASIN

夏在连 刘树根 时华星 周文 朱强 徐国强 徐国盛 雍自权

Xia Zailian Liu Shugen Shi Huaxing Zhou Wen Zhu Qiang Xu Guoqiang Xu Guosheng Yong Ziquan

成都理工大学, 油气藏地质及开发工程国家重点实验室, 成都, 610059 2. 中国石油化工股份有限公司, 胜利油田分公司, 山东, 东营, 257001

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu, Sichuan 610059, China 2. Shengli Oilfield Branch Company, SINOPEC, Dongying, Shandong 257001, China

对中伊朗盆地Arn-2井和Fkh-1井2 300~3 300 m的库姆组灰岩在模拟地层条件下(包括围压、温度、孔隙饱和流体和取样方向)的岩石力学性质进行了测定.所测岩石的压缩变形特征按应力—应变曲线形态可分为2种类型:弹性变形和弹—塑性变形.绝大多数样品表现为脆性,破坏前的总轴向应变一般不超过3%,大多为1%左右.所有岩心样品由于其埋藏深度差异较大,力学参数的变化范围也较宽.所有样品的抗压强度介于46.52~288.31 MPa;杨氏模量介于11.00~286.53 GPa.Fkh-1井库姆组E段抗压强度、杨氏模量和泊松比均大于Arn-2井库姆组E段.同时Fkh-1井库姆组内抗压强度A段大于C段大于E段,反映了岩石抗压强度随深度增大而变大.地层条件下流体对Fkh-1井岩石力学性质的影响主要是岩石饱油抗压强度大于饱水抗压强度,岩石饱油杨氏模量大于饱水杨氏模量.当样品中存在薄弱面时,会显著地降低岩石的抗压强度和杨氏模量;多数样品平行层理方向的抗压强度和杨氏模量与垂直层理方向的抗压强度和杨氏模量不等.

The rock mechanical properties of the limestone samples from the Qum Formation between 2 300 m to 3 300 m in Well Arn-2 and Well Fkh-1,the central Iran Basin have been studied under the simulated formation conditions(including the confining pressure,the temperature,the type of the pore-saturating fluid,and the direction of sampling).The results indicate that the compressional deformation characteristics of the rock samples can be classified into 2 types according to the shape of the stress-strain curves: elastic deformation and elastic-plastic deformation.Almost all samples show brittle failure under the formation conditions,with the total axial pre-failure strain being normally less than 3%,and being mostly about 1%.The change scope of the mechanical parameters of all samples are broad due to the great differences in the burial depth;the compressive strength is 46.52 to 288.31 MPa;and the range of Young's modulus is 11.00 to 286.53 GPa.The compressive strenghty,the Young's modulus and the Poisson's ratio of Member E of the Qum Formation in Well Fkh-1 are all greater than those of Member E of the Qum Formation in Well Arn-2.While within the Qum Formation in Well Fkh-1,the compressive strength is greater in Member A than that in Member C than that in Member E,indicating that the compressive strength increases with depth.The effect of the fluid on the mechanical properties in Well Fkh-1 is as follows: the compressive strength and the Young's modulus of the oil-saturated rocks are greater than the compressive strength and the Young's modulus of the water-simulated rocks respectively.When the weak planes pre-exist in the rocks,the compressive strength and the Young's modulus remarkably decrease.For most samples,the compressive strength and the Young's modulus in the direction parallel to the bedding plane are different to those perpendicular to the bedding plane.

国家重点基础研究发展计划(973计划)项目(2005CB422106)

https://doi.org/10.11781/sysydz200801086