381 Ma rhyolite found by Nanling scientific drilling in Qingbaikouan System

Nanling scientific drilling(NLSD-1)is located at the junction of Yudu-Ningdu-Xingguo county in Jiangxi Province. Tectonically,the hole site of NLSD-1 is located at the intersection of Wuyi and Luoxiao block inside the Cathaysian plate. NLSD-1 aims at solving the scientific problems of regional geology and metallogenic regularity in the ore concentration area. The NLSD-1 hole intersects Qingbaikouan strata at 1373.71 m which are composed of a rhythm layer of tuffaceous volcanic clastic rock consisting of tuffaceous siltstone, tuffaceous sandstone, variable tuff, tuffaceous slate and rhyolite. Based on detailed geological logging and identification of different kinds of lithostratigraphy under microscope, the authors selected zircons from the rhyolite of NLSD-1. A set of high harmonic isotopic ages were obtained by using LA-ICP-MS, which can be used to make sure that the formation age of rhyolite is 381 Ma. This datum provides new information for the further division, assignment and study of geological evolution of stratigraphic age of Late Proterozoic in the middle south area of Jiangxi Province.