Discovery of Late Paleozoic Detrital Zircons in Lishui Sag, East China Sea, and Its Significance

Abstract:

Detrital zircons were selected for UPb isotopic dating from Yueguifeng Formation (YF) and Lower Lingfeng Formation(LF) of the well N6 in Lishui Sag, East China Sea Shelf Basin. The results show that detrital zircons in YF are mainly magmatic zircons formed between 14090 Ma and 190170 Ma, while others are minor and mostly metamorphic zircons, older than 400 Ma in age. Apart from the above age populations, metamorphic zircons formed in 280260 Ma appeare in LF. This indicates that the provenance of YF is mainly magmatic rocks of 14090 Ma and 190170 Ma. With sustained erosion of the source area, metamorphic rocks that formed in 280260 Ma are significantly exposed and added. These permian detrital zircons with metamorphism may be related to the convergence between paleo Pacific plate and South China.