Fluid inclusion and H-O-S-Pb isotope systematics of the Chayong Cu-polymetallic deposit,Sanjiang Metallogenic Belt,Qinghai Province,China  

作　　者：Jian Wang Hao Wang Fengyue Sun Fei Wang Xiangwen Li Hongju Yue 

机构地区：[1]School of Mining Engineering,Heilongjiang University of Science and Technology,No.2468 Puyuan Street,Harbin 150022,People’s Republic of China [2]Ang’angxi Physical Geological Data Field Observation and Research Station of Heilongjiang Province,Qiqihar 161031,People’s Republic of China [3]College of Earth Science,Jilin University,Changchun 130061,People’s Republic of China [4]The Six Geological Prospecting Institute of Heilongjiang Province,Jiamusi 154002,People’s Republic of China

出　　处：《Acta Geochimica》2024年第6期1153-1168,共16页地球化学学报（英文）

基　　金：The current research was supported by Heilongjiang Province General University Youth Innovation Talent Training Program Project(UNPYSCT-2020030)。

摘　　要：The Chayong Cu-polymetallic deposit is a recently discovered Cu-polymetallic deposit hosted in the Sanjiang Metallogenic Belt within the Tibetan Plateau of China to the northeast of the North Qiangtang terrane.The ore body occurs in siltstone and is controlled by a northwest-trending fault structure.According to the associations,assemblages,and cutting relationships between ore veins,the hydrothermal mineralization period can be divided into three mineralization stages:(1)a molybdenite mineralization stage,(2)a Cu-polymetallic sulfide stage,and(3)a quartzcarbonate stage.Two types of fluid inclusions(FIs),namely,liquid and vapor-rich inclusions,are present in quartz as so ciated with sulfide minerals.Early-stage FIs are both iquid and vapor-rich,homogenized at temperatures ranging from 364.1 to 384.2℃,and have salinities ranging from0.70%to 9.60%NaCl equivalent(eqv).The middle-stage FIs are also both liquid-and vapor-rich,homogenized at temperatures ranging from 272.4 to 355.6℃,and have salinities ranging from 0.53%-17.10%NaCl eqv.The late-stage FIs are liquid,homogenized at temperatures ranging from 209.4to 255.3℃,and have salinities ranging from 0.35%-6.87%NaCl eqv.The samples from the deposit haveδ^(34)S values of-21.8‰to-19.2‰and-5.5‰to-6.0‰,suggesting that sulfur was derived from the host sediments and magmatic fluids,respectively.The metallic minerals within the deposit have^(206)Pb/^(204)Pb,^(207)Pb/^(204)Pb,and^(208)Pb/^(204)Pb values of 18.439-18.458,15.656-15.679,and 38.772-38.863,respectively,suggesting that the metals were derived from the upper crust and orogenic belts.The samples from the deposit haveδ^(18)O_(W)values of 2.99‰-7.99‰andδD_(W) values ranging from-84.4‰to-73.9‰,indicating that the pre-forming fluids were magmatic and mixed with minor amounts of meteoric water.The ore-forming fluid of the Chayong copper polymetallic deposit was a high-temperature,medium-to low-salinity H_(2)O-NaCl-CH_(4)-N_(2)±CO_(2)fluid system.The early high-temperature magmatic fluid,due to b

关 键 词：Fluid inclusions S isotope Pb isotope H-O isotope Chayong Cu-polymetallic deposit Sanjiang Metallogenic Belt YUSHU Qinghai 

分 类 号：P597[天文地球—地球化学] P618.2[天文地球—地质学]