Source characteristics and genesis of Sb mineralization from the Au and Sb deposits of the Youjiang Basin,SW China:constraints from stibnite trace element and isotope geochemistry  

作　　者：Aizat Zhaanbaeva Keqiang Peng Abiola Oyebamiji Kyiazbek Asilbekov 

机构地区：[1]State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Institute of Geology of National Academy of Sciences of Kyrgyz Republic,Bishkek 720000,Kyrgyzstan

出　　处：《Acta Geochimica》2021年第5期659-675,共17页地球化学学报（英文）

基　　金：the National 973 Program of China(2014CB440906)。

摘　　要：The Youjiang Basin is characterized by a wide distribution of Au and Sb deposits.These deposits are mainly hosted by sedimentary rocks from Cambrian to Triassic and are structurally controlled by faults and folds.Three types of Sb mineralization can be distinguished based on geologic characteristics,economic metals,and mineral associations.The first type is dominated by Sb mineralization but contains minor or little Au,similar to the large Qinglong deposit.The second type has a spatial association with the gold deposit but formed independent Sb mineralization,reminiscent of the Badu deposit.In the third type,Sb generally formed as an accompanying element in the Carlin-type gold deposit,and stibnite occurred as euhedral crystals filling the open space and faults in the late stage of gold mineralization,analogous to the Yata deposit.Trace element concentrations and sulfur isotopic ratio of stibnite,and oxygen isotope of stibnite bearing quartz were analyzed to infer the ore source(s)for Sb mineralization and genesis.To distinguish the various types of stibnite mineralization between the deposits,Cu,Pb,and As have recognized most diagnostic,with an elevated concentration in Au and Au-Sb deposits and depleted in Sb deposit.Theδ34S isotopic composition of stibnite samples from three deposits show a wide variation,ranging from-6.6%to+17.45%.Such isotopic values may indicate the sedimentary sulfur source,introduced by fluid–rock interaction.On the other hand,fluid mixing of several end members cannot be excluded.The calculatedδ18O isotopic data of Sb-bearing quartz show the initial ore fluid in Au and Au-Sb deposits most likely have a magmatic or metamorphic origin that enriched during fluid–rock interaction,and Sb deposit characterized by initial meteoric water.From these data,we proposed that different lithologies,fluid–rock interaction,fluid pathways,and different ore fluids controlled the compositional evolution of fluids,which might be the main reason for the diversity of Au or Sb mineralization.

关 键 词：Trace elements Stable isotope Sb mineralization Youjiang Basin SW China 

分 类 号：P618.66[天文地球—矿床学] P597[天文地球—地质学]