南图尔盖盆地Aryskum坳陷中侏罗统多尚组储层敏感性研究

Study on Reservoir Sensitivity of the Upper Jurassic Duoshang Formation in the Aryskum Depression,South Turgay Basin

南图尔盖盆地Aryskum坳陷油气资源丰富,Aryskum坳陷中侏罗统多尚组作为主力产层,储层非均质性及黏土矿物发育情况不甚理想,储层敏感性对油气开采存在较大影响,因此储层敏感性研究迫在眉睫.根据储层岩石结构、胶结物等基础特征,对Aryskum坳陷中侏罗统多尚组开展敏感性流动实验.结果表明:中侏罗统多尚组储层具有中等偏强水敏感性、弱-中等偏强速敏感性、无-弱碱敏感性及弱酸敏感性.深入研究发现蒙脱石及伊蒙混层相对高含量是造成储层中等偏强水敏感性的直接原因;高岭石含量及孔喉结构决定了储层弱-中等偏强速敏感性;储层酸碱敏感性较弱,另外部分高方解石及白云石充填储层酸化改善效果明显.

The Aryskum depression in the South Turgai Basin is rich in oil and gas resources.The Middle Jurassic Duoshang formation in Aryskum depression is the main production section,the reservoir heterogeneity and clay mineral development are not very good,and the reservoir sensitivity has a great impact on oil and gas production,so the study of reservoir sensitivity is urgent.Based on the characteristics of reservoir rock structure and cements,the core sensitivity flow experiment of Duoshang formation of Middle Jurassic in Aryskum depression is carried out.The results show that the Doshang Formation of Middle Jurassic reservoir has moderate to strong water sensitivity,weak-moderate velocity sensitivity,no-weak alkali-sensitivity and weak acid sensitivity.It is found that the relatively high content of montmorillonite and illite montmorillonite is the direct cause of medium to strong water sensitivity.Kaolinite content and pore-throat structure determine the weak-moderate high-velocity sensitivity of the reservoir.The sensitivity of acid and alkali is weak,and the acidification improvement effect of some high calcite and dolomite filling reservoirs is obvious.