东营凹陷古近系孔店组成岩特征及对储层的控制

Diagenetic character and controling factor of reservoir of Kongdian Formation of Paleogene in Dongying basin

通过岩石薄片、扫描电镜、镜质体反射率、X衍射、物性分析等资料,对东营断陷盆地古近系孔店组成岩作用进行研究。结果表明:原始碎屑组分和化学沉积分异作用引起的早期胶结物性质决定了后期的成岩演化;典型成岩现象有强烈压实作用、硬石膏胶结、多期次碳酸盐胶结、多期次粘土矿物胶结、硅质强烈胶结、矿物强烈穿插交代、碎屑颗粒和胶结物的溶解作用,各种成岩现象对深部碎屑岩储层均产生重要影响。同时也证实:压实作用是引起深部碎屑岩强烈致密化的主要原因;硬石膏胶结、碳酸盐胶结和硅质胶结是引起致密化的又一重要原因;长石、碳酸盐胶结物的溶解作用是引起该地区储层改善的主要成岩因素。

Based on the analysis of thin-section,scanning electron microscopic observation,vitrinite reflectance,X-diffraction and physical quality,the paper studied in detail the diagenesis of Kongdian Formation in Dongying sag.It is indicated that the original clastic component and the early cementation generated by the sedimentary dif-ferentiation determined the prost diagenetic process.The typical diagenetic phenomenon includes the intensive compaction,anhydrite cementation,multiperiod carborate cementation,multiperiod clay minerals cementation,in-tensive siliceous cement,intensive interpenetration replacement between minerals,solution of calstic and cementa-tion,which influences deeply the reservoir of the deep-seated clastic rocks.The conclusion has been verified that compaction was the main cause of high pyknosis of the deep-seated clastic rocks,another cause was the cementa-tions of anhydrite,carborate and siliceous,solution of feldspar and carbonate cementation was the main diagentic cause of improved reservoir.