Study on the Tectonic Evolution in Central and Northern of Jiangnan Orogeny by Thermal Chronology

The isotope age distribution and frequency distribution histogram of Jiangnan orogeny were analyzed in this paper. Through measuring U-Pb, Sm-Nd, Rb, Sr, K-Ar, 40Ar/39Ar isotope and fission track in sealing temperature, the evolution history in Jiangnan orogeny was divided into four stages. New archean-paleoproterozoic tectonic thermal event, Proterozoic tectonic magmatic event, tectonomagmatic events during Jinning period, and early Paleozoic to Cenozoic tectonic thermal event were happened in 2958~2421 Ma, 2137~1625 Ma, 1379~726 Ma, and 445~45 Ma, respectively. Each construction phase could be divided into the different period of time. There were three long time tectonic thermal halcyon period between the four stages, which suggested that the tectonic movement was intermittent, not persistent in Jiangnan orogeny.