LI Min-tong1,2,3, LI Zhong-quan1,2
( 1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, Chengdu 610059, China;
2. Key Laboratory of Tectonic Controls on Mineralization and Hydrocarbon Accumulation of Ministry of Land and Resources, Chengdu 610059, China;
3. Hydro-Engineering Party of Sichuan Metallurgical Geology and Exploration Bureau, Chengdu 611730, China )
Abstract: .Nagengkangqieer silver deposit is located in the central part of the Eastern Kunlun Mountains. Ore bodies occurring as vein are mainly hosted in gneiss of the Jinshuikou Group and Late Paleozoic granodiorite and monzonitic granite. Based on the study of geological characteristics of deposit, twelve samples of sulfides and calcites were studied with S-Pb-C-O isotopes analysis. Sulphur isotope values range from -3.4‰ to 0.6‰,implicating that the sulfur sources were probably derived from magmatism process. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of sulfides range from 18.28 to 18.62, 15.6 to 15.73, and 38.38 to 39.10, with an average of 18.37, 15.65, and 38.63, respectively. Most of Pb isotope compositions were plot in the field of the upper Pb evolution curve. Carbon and oxygen isotope compositions range from -6‰～ to 2.8‰ and 6.1‰ to 20.5‰,with an average of -4.25‰ and 12.49‰, respectively, suggesting that the carbon was mainly derived from magmatism. Geological and isotopes studies of Nagengkangqieer silver deposit reveal that the deposit is similar to the postmagmatic hydrothermal type controlled by structure and magmatism.
Keywords: silver deposit; S-Pb-C-O isotope; Sulfide; Calcite; the Eastern Kunlun Mountains
E-mail: 281455812@qq.com
ACTA MINERALOGICA SINICA Vol. 37, No. 6, 2017, Page 771-781
