| PDF: | |
| Time: | 2004 |
| Journal: | Marine Geology & Global Geology |
| Volumn: | 24 |
| Issue: | 2 |
| Pages: | 55-59 |
| Type: | Other |
| Author: | Rihui Cheng,Pujun Wang,Wanzhu Liu,Huafeng Tang,Qingying Kong,Weihai Song |
Abstract: | The deep sea sedimentary association of nodular limestone, thin-layered micrite limestone, muddy limestone and mudstone represents themaximum flooding event of transgression of the Triassic, developed in CangbomenMember, Qinglong Formation of early-middle Triassic, which is 242～244Ma, early-middle Olenkian.The initiation of long-term relative sea level rise was composed of five short terms that stared at early Triassic,and reached itsmaximum at the middle Olenkian.After then a great regression began, and through Anisian, Ladinian and Carnian the seawater withdrew from lower Yangtze area completely at Norian-Rhaetian.However, themaximum transgression of long-term global sealevel changeswas at 221 Ma, early Norian.The time of maximumflooding event in lower Yangtze areawas earlier about 22 Ma than that of the global maximum flooding, suggesting a clear non-synchronization.This non-synchronization reflected the great changes of the tectonic setting during middle-late Triassic, which was the collision between the Yangtze plate and North China plate.The non-synchronization of the Triassic in lower Yangtze area can be a stratigraphic proof of the collision between the Yangtze plate and North China plate. |