高含黏土岩心有效孔隙度实验新方法——以准噶尔盆地玛湖凹陷上乌尔禾组砾岩储层为例  

New experimental method for effective porosity of high clay content cores:a case study on conglomerate reservoirs of Upper Urho Formation in Mahu sag,Junggar Basin

作　　者：张浩[1] 毛锐[2] 金力新 申子明 ZHANG Hao;MAO Rui;JIN LiXin;SHEN ZiMing(Exploration Department of Xinjiang Oilfield Company,PetroChina,Karamay 834000,China;Research Institute of Exploration and Development of Xinjiang Oilfield Company,PetroChina,Karamay 834000,China)

机构地区：[1]中国石油新疆油田公司勘探事业部,克拉玛依834000 [2]中国石油新疆油田公司勘探开发研究院,克拉玛依834000

出　　处：《地球物理学进展》2022年第4期1669-1676,共8页Progress in Geophysics

基　　金：国家科技重大专项“准噶尔盆地岩性地层油气藏富集规律与目标评价”(2017ZX05001-004)资助。

摘　　要：准噶尔盆地玛湖凹陷二叠系砾岩储层黏土矿物含量高,行业标准测量法的烘干温度过高、烘干时间过长、烘干湿度不适宜,会造成高含黏土岩心黏土束缚水被烘干,进而导致有效孔隙度测量不准.为此,通过对比不同测量环境下核磁共振实验结果,明确高含黏土岩心在低温(55℃)、保湿(相对湿度65%)的环境下测量有效孔隙度,黏土束缚水不被烘干.利用烘干过程中电阻增大率的拐点确定可动流体孔隙、毛管束缚流体孔隙的烘干时间,进而确定了岩心的有效孔隙度.与行标测量法相比,本文的方法更能反映目标区地质特征,展现出良好的应用效果.Due to the high content of clay minerals in the Permian clastic reservoirs in Mahu sag, Junggar basin, too high drying temperature, too long drying time and unsuitable drying humidity of the standard porosity measurement method will result in the drying of the clay-bound-water with high clay content cores, which leads to the inaccurate measurement of the effective porosity. Therefore, by comparing the results of NMR experiments in different measurement environments, it is clear that the measurement environment of effective porosity of high clay content core is low temperature(55℃) and wet(relative humidity 65%), which can ensure that the clay-bound-water does not dry. The inflection point of the resistance index during the drying process is used to determine the drying time of the movable fluid pores, capillary bound fluid pores and clay-bound-water pores, and then the effective porosity of the core is determined. Compared with the line standard survey method, the method presented in this paper can better reflect the geological characteristics of the target area and show good effect.

关 键 词：高含黏土岩心 有效孔隙度 测量环境 黏土束缚水 核磁共振T2谱 电阻增大率 

分 类 号：P631[天文地球—地质矿产勘探]