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合肥—潢川盆地南缘中生代地层被划分为4个年代体(Chronsome)。年代体包括早侏罗世防虎山组和中晚侏罗世圆筒山组下部,由辫状河、曲流河以及滨-浅湖沉积体系组成,局限于盆地东端;年代体包括中—晚侏罗世三尖铺组、朱集组和圆筒山组上部,下部为冲积扇沉积,中、上部为辫状河沉积,早期属于横向水流系统(南北方向),晚期是纵向水流系统(东西方向),近EW向的信阳—金寨—舒城断裂是其南部边界;年代体包括早白垩世早期凤凰台组、段集组、周公山组,前两组为冲积扇沉积,后者为辫状河和越岸沉积,粗碎屑明显向盆进积达数公里,南部边缘发育横向水流,而往盆地方向发育纵向水流。年代体为早白垩世晚期黑石渡组和陈棚组,南部边界是磨子潭—晓天断裂和桐柏—商城断裂,断裂以伸展—走滑为主,东段早期为冲积扇—扇三角洲沉积,晚期为深湖浊积岩沉积。晚白垩世沉积仅发育在西段局部地区,其余处于隆升状态。平行于大别山造山带的近EW向纵向断裂控制着年代体的南部边界,NE向郯城—庐江断裂和商城—麻城断裂控制着年代体侧向相的变化。合肥—潢川盆地南缘沉积从东往西逐渐超覆,揭示大别造山带折返具有自东而西的递进特征。郯城—庐江断裂和商城—麻城断裂对年代体的发育有明显影响,郯城—庐江断裂控制着早侏罗世沉积,表明构造活动至少始于早侏罗世。
The Mesozoic strata in the Hefei-Huangchuan basin are divided into four Chronsomes. Chronostratigraphy includes the Early Jurassic anti-Hushan Formation and the lower Middle Jurassic Member of the Cylindrical Group, which consists of braided, meandering and coastal-shallow lake sedimentary systems and is confined to the eastern end of the basin; The upper and lower parts of the Sanjianpu Formation, the Zhuji Formation and the Cylindrical Formation of the Jurassic are alluvial fan sediments, while the upper and middle parts are braided river sediments. The early period belonged to the lateral flow system (north-south direction) and the late stage was the longitudinal flow system (east-west direction) , The Xinyang-Jinzhai-Shucheng fault in the near EW direction is the southern boundary; the Chronostrae include the Early Early Cretaceous, the Fenghuangtai Formation, the Duanji Formation and the Zhougongshan Formation. The first two groups are alluvial fan deposits and the latter are braided River and overbank deposition, coarse clastic obviously influx of basin up to several kilometers, the southern edge of the development of lateral flow, while the longitudinal direction of the basin to the development of water flow. In the Early Cretaceous, the Heishidudu Formation and the Chenpeng Formation are the Early Cretaceous. The southern boundary is the Mozi Lake-Xiaotian and Tongbai-Shangcheng faults, and the faults are mainly extensional-strike slip. The early Eastern segment is alluvial fan-fan delta Sedimentary, Late Sedimentary sediments. Late Cretaceous sediments only in the western part of the region, the rest in uplift state. The longitudinal EW faults parallel to the Dabieshan orogenic belt dominate the southern boundaries of the Chronostratigraphy and the NE Xiangtan-Lujiang fault and Shangcheng-Macheng fault control the lateral body facies changes. The deposition of the Hefei-Huangchuan basin in the southern margin gradually overrides from east to west, revealing that the Dabie orogen has a gradual east-west character. The Tancheng-Lujiang fault and the Shangcheng-Macheng fault have a significant impact on the development of the Chronology. The Tancheng-Lujiang fault controlled the deposition of the Early Jurassic, indicating that tectonic activity started at least in the early Jurassic.