摘要：

皖南东至地区寒武系在地层分区上可以分为下扬子地层分区、过渡地层分区和江南地层分区，生物群上出现了两区特征分子和过渡区的混生现象，并处于台地与盆地交接部位。通过对分别位于台地、斜坡和盆地露头层序地层研究，将寒武纪地层自下而上划分为三个Ⅱ类沉积层序和二个Ⅰ类沉积层序，早寒武世的三个Ⅱ类沉积层序的陆架边缘体系域不发育；中寒武世晚期到晚寒武世的二个Ⅰ类沉积层序皆由低水位体系域、海侵体系域和高水位体系域 组成三元结构。通过层序地层分析和沉积体系演化建立了相应的海平面变化曲线，自早寒武世早期本区海平面达到最高位和最大上升速率后，至寒武纪末研究区海平面总体处于下降过程，即海平面为累进式的缓慢的下降。

Abstract:

The Cambrian in the Dongzhi region, southern Anhui, are distributed in three stratigraphic subregions: Lower Yangtze, Jiangnan and the transitional subregions. Each of former two subregions has its own characteristic components for their biota while the transitional subregion has mixed components for its biota. The Dongzhi region is located at the junction between the platform and basin. Sequence stratigraphic study on the outcrops at the platform, ramp and basin has revealed that the Cambrian in this region can be subdivided into three type-II and two type-I depositional sequences from bottom to top. The SMSTs of three typeⅡ sequences of the Early Cambrian are not developed. The two type-II sequences of the late Middle and Late Cambrian are all composed of LST, TST and HST. By analysis of the sequence stratigraphy and the evolution of the sedimentary system tracts, the curve of The sea level curves of these periods have been reconstructed based on analyses of sequence stratigraphy and evolution of depositional systems. The sea level attained its highest position with a fastest rise in the early Early Cambrian. Since then, from the middle Early Cambrian to the end of the Late Cambrian, the sea level experienced a slow, gradual drop.