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徐宿地区震旦系为陆表浅海沉积 ,沉积相以碳酸盐台地相为主。在潮上 -潮下低能沉积中 ,常间有阵发性高能沉积 ,并伴生有异常沉积构造。这些异常沉积构造及同生阶梯状小断裂多为古地震遗迹 ,据此可识别出五个古地震遗迹密集分布层段。在研究区至少有两次浅成 超浅成基性岩浆侵入活动 ,分别发生在早震旦世和晚震旦世。地震事件、岩浆侵入事件与海平面升降有成因联系。研究表明 ,研究区震旦纪地质事件受控于伸展构造 ,地质事件发生于 738.6～ 60 4Ma之间。这一时限与中 -新元古代超大陆Rodinia在 780～ 60 0Ma逐步裂解的时间是一致的 ,因而徐宿地区震旦纪地质事件的起因可能与Rodinia的裂解过程有关。由“古郯庐裂陷带”至北秦岭北部边界断层北侧可能就是当时华北板块边缘的板内裂解带
The Sinian area in Xu-Su area is mainly shallow-sea sediments on the surface of the land and the sedimentary facies is dominated by carbonate platforms. In the tide - tidal low-energy deposition, there are often paroxysmal high-energy deposition, accompanied by anomalous sedimentary structure. These anomalous sedimentary structures and synoptic small faults are mostly paleo-earthquake relics, thus identifying five closely-spaced seismic intervals. There are at least two shallow and super-shallow magmatic intrusions in the study area, which occurred in early Sinn and Late Sinian, respectively. Earthquakes, magmatic intrusions and sea level rise and fall have a genetic connection. The study shows that the Sinian geological events in the study area are controlled by extensional structures and the geological events occur between 738.6 and 604Ma. This time-period coincides with the time of the mid-Neoproterozoic Rodinia supercontinent in 780 ~ 600Ma. Therefore, the origin of the Sinian geological events in Xu-Su area may be related to the cracking process of Rodinia. The northern fault from the “ancient Tanlu rift zone” to the north Qinling Mountains may be the intraplate splitting zone at the edge of North China Plate