济阳坳陷古近系深层自生矿物与孔隙演化规律

he clastic rocks in the depth of 2800-6000m of the Paleogene in Jiyang sub-basin are experiencing middle diagenesis and late diagenesis. The reservoirs in main areas of the sub-basin develop 2-6 secondary pores zones. The reservoirs in the stage A of middle diagenesis of Bonan fault zone in Zhanhua depression and the gentle slope belt of Chezhen depression are controlled by the acidic diagenetic medium and develop one secondary pores zone respectively in each diagenetic sub-stage. The contents of autogenic quartz, pyrite and kaolinite are quite high in these reservoirs. The reservoir’s diagenetic environment and authigenic minerals characteristics in the stage A1 of middle diagenesis of Chengnan fault zone in Zhanhua depression are similar to those in the above areas, and develop one secondary pores zone too. The reservoirs in the other areas of Jiyang sub-basin have mulriple diagenetic environments, alternating between acidic and alkali environment, which make the evolution characteristics of authigenic minerals complex. The reservoirs in the middle A diagenesis stage of the steep slope zones of Dongying depression and Chezhen depression and Bonan deep sag of Zhanhua depression develop four secondary pores zones respectively. The reservoir in the stage A2 of middle diagenesis of Chengnan fault zone in Zhanhua depression develops two secondary pores zones. There is one secondary pores zone respectively in the reservoirs of the middle B diagenesis stage of the steep slope belt of Chezhen depression and of the stage from the middle B to the late diagenesis of Minfeng area of Dongying depression.