LIU Xuelong1,2), YANG Zhiming2), LU Yingxiang3), MEI Shehua4), ZHANG Na1), ZHU Jun1,3), CHEN Jianhang1), LUO Ying1), LI Zhenghuan1)1) Kunming University of Science and Technology, Kunming, Yunnan, 650093, China
Abstract:The Zhongdian area is located in the southern edge of the Sanjiang Cu-Mo-Pb-Zn-Au polymetallic aggregation area, which is a unique Cu-Mo multi-metal composite superimposed ore belt. In this paper, zircon fission track (ZFT)and apatite fission track(AFT) analysis tests were performed on the Late Cretaceous Tongchanggou, Xiuwacu, and Relin metallogenic porphyry using fission track low-temperature thermochronology technology. And we conducted tectonic thermal history evolution simulations since the Late Cretaceous, revealing the tectonic-magmatic mineralization events and thermal history evolution processes in this area. Studies have shown that the age of ZFT varies between 52±2～96±5Ma, the age of AFT varies between 15±1～48±3Ma, the age of the center and the pool are basically the same. The fission track analysis of zircon and apatite revealed that the Zhongdian area of Yunnan has experienced three stages of tectonic thermal events since the Late Cretaceous. The first stage (96~60Ma), It is mainly the thermal history evolution stage of rapid cooling after magmatic emplacement; the second stage (52~39Ma) is a slow cooling process; The third stage (16~15Ma) reveals that the area experienced a rapid cooling geological evolution due to the impact of uplifting orogeny on the Qinghai-Tibet Plateau since the Miocene. Thermal history inversion results of ZFT and AFT shown that the typical Late Cretaceous ore-forming porphyry have similar uplift processes and denudation history in the Zhongdian area, and obtained the quantitative calculation results of amount and rate of the erosion, it provide a scientific reference for the resource potential evaluation and exploration in the area.