There are 5 depositional systems in the region . they are panne and jishan delta systems coming from chengning heave near the northwest border of the region , shuangfeng delta located in southwest part of the region coming from luxi dome , qudi fan - delta located in the southeast of the studying area and the sub - fan near fault or fan - delta of the southern part of the region . based on the study of sedimentary facies and depositional systems , 11 lithological traps are predicted 在等时地层格架内对沙三段各中期基准面旋回内的沉积相和沉积体系进行了详细研究，确定了沙三段沉积时期发育的五种沉积体系类型，即来自凹陷西北边界埕宁凸起的盘河三角洲体系和基山三角洲体系、来自鲁西隆起、分布在凹陷西南部的双丰三角洲体系、东南部的曲堤(扇)三角洲体系，南部的近岸水下扇/扇三角洲体系。
