济阳孔店转型期识别标志及盆地特征

The recognition indicator of Kongdian transformation period and the characteristics of basin in Jiyang area

济阳地区孔店组与上覆地层的分界线,一直是困扰着孔店组构造层序石油地质研究与勘探的关键问题,笔者通过区域地震大剖面的研究,首次从地震剖面找到了孔店组顶、底不整合界面,为研究孔店组原型盆地奠定了基础.研究发现东营凹陷孔店组盆地与沙河街组盆地同受北部控盆断层控制,控盆断层东部为北西向,向西转为近东西向,东部可见小角度的角度不整合;而惠民凹陷孔店组盆地受北掉的南部北东向断层系控制,形成南断北超的半地堑,与上覆沙河街组北断南超半地堑叠置,孔店组与沙四段之间有明显跷跷板现象,沙四段向南翘倾作用使得孔店组根部地层大幅度剥蚀,产生孔店组与上覆地层之间明显角度不整合.东营与惠民凹陷的孔店组盆地通过林樊家～青城构造调节带衔接,济阳地区北部沾化凹陷、车镇凹陷孔店期为零星小盆地,孔店组的油气勘探重点应放在东营与惠民,由于东营孔店组盆地所受的改造相对较少,应为首选目标.

Based on research on regional seismic profiles, top and bottom unconformities of Kongdian Formation are recognized and it is useful for the study of Kongdian Formation prototype basin. Kongdian Formation basin and Shahejie Formation basin in Dongying sag are controlled by faults, which tend towards north-west in the eastern part and east-west in the western part. There is small-angle unconformity in eastern Dongying sag. Kongdian Formation basin in Huimin sag is controlled by north-eastern faults and half grabens are formed with fault in southern part overlap in northern part. Such half grabens are covered by Shahejie Formation half grabens with fault in northern part overlap in southern part. There is obvious angle unconformity between Kongdian Formation and above strata because of the tilt and plunge of Shasi strata and the erosion of the root-part strata of Kongdian Formation. Kongdian Formations in Dongying sag and Huimin sag are linked up by Linfanjia-Qincheng structural belt. Basins during Kongdian period are small and scattered in Zhanhua sag and Chezhen sag in northern Jiyang area, so the prospecting emphases should be Dongying and Huinmin sag. Kongdian Formation in Dongying sag are reconstructed relatively slightly and may be primary prospecting target.