广安地区侏罗系凉高山组粘土矿物研究

四川广安地区侏罗系粘土矿物类型主要为绿泥石、高岭石、伊蒙混层和伊利石;同一口井随着深度的增加,伊利石、绿泥石含量增加,伊蒙混层中的蒙脱石混层比降低。粘土矿物特征与储集层物性的相关性分析认为:伊蒙混层含量、伊利石含量均与储集层孔渗性能呈负相关,绿泥石与高岭石含量与储集层孔渗性呈正相关;通过对伊蒙混层中蒙脱石的混层比的计算,大多数为有序混层,说明该区凉高山组处于生油高峰期,这与岩石中TOC(%)介于0.8与1.3,Ro(%)介于0.7与1.2相吻合。

Clay Mineralogy of the Jurassic Lianggaoshan Formation in the Guang'an Region

The clay minerals in the Jurassic Lianggaoshan Formation in the Guang＇an region, Sichuan consist of chlorite, kaolinite, illite/smectite mixed layer and illite based on the X-ray diffraction and SEM observation. Illite and chlorite increase with the depth, while smectite of illite/smectite mixed layer decreases with the depth, Study of correlation of clay mineral with petrophysical property indicates that content of illite and illite/smectite mixed layer shows an inverse correlation to the porosity and permeability of the reservoir, while content of chlorite and kaolinite shows a positive correlation to the porosity and permeability. According to the calculation of smectite mixed layer ratio of illite/smectite mixed layer, the Lianggaoshan Formation with TOC of 0.8-1.3 and Ro of 0.7-1.2 in the Guang＇an region is in the peak oil period.