鲁西中新生代盆地充填序列及盆地类型

Mesozoic-Cenozoic sedimentary sequence and depositional basin types in the western Shandong.

针对鲁西中新生代盆地的沉积特征,结合野外地质露头调查及区域地质调查成果,对中新生代盆地充填序列及盆地类型进行了研究。盆地内的侏罗纪—白垩纪沉积序列是一套以河流相为主的碎屑岩沉积组合,新生代古近纪沉积序列则以湖相为主,河流相为辅。中生代沉积序列形成于低角度拆离断层的上盘,物源主要来自断层下盘,具有轴向和径向水流特征;新生代沉积序列物源主要来自断层上盘,以轴向水流为特征。这些特征与伸展作用过程中形成的拆离型盆地和裂谷型盆地的特征完全一致。鲁西中新生代盆地具有北断南超的箕状断陷盆地结构,现今的盆岭相间格局可能发生于侏罗纪。

In view of depositional feature of Mesozoic -Cenozoic in Western Shandong Province,sedimentary sequence and basin types were researched according to the information of field geological outcrop and regional geology survey.Jurassic-Cretaceous sedimentary sequence in the area mainly is clastic rock assemblage with fluvial facies,but Paleogene sediments dominantly consist of lacustrine sediments subordinate fluvial sediments.Mesozoic sediments were derived from hangingwall and formed above a low-angle normal fault system with axial and transverse transport paths.The depocenter was far from the northern margin of basin.Cenozoic sediments originated from footwall with axial transport paths predominantly.All of the features were coincident with the characters of detachment and rift basin,which were formed by extensional movement.The basin is a dustpan downfaulted basin which is north-snap and south-super in luxi meso-cenozoic,and presently basin-mountain physiognomy possibly formed in the Jurassic.