In Situ Trace Elements and Sulfur Isotope Analysis of Pyrite from Zaozigou Gold Deposit:Implications for Ore Genesis
Zaozigou is a representative gold deposit in West Qinling orogenic belt.The source of ore-forming materials and the genetic type of the deposit are still in debate.The microstructure,trace elements and sulfur isotopes of gold-bearing pyrite were analyzed by LA-ICP-MS to constrain the source of ore-forming materials and ore genesis.Pyrite can be divided into at least three generations(Py1,Py2 and Py3),of which Py2 and Py3 are the main gold-bearing minerals.Py1 is characterized by high Pb and low Ag,Au,W,and Tl contents.The δ34S values of Py1 range from-7.4‰ to-5.8‰.The Au,As,Ag,and W contents of Py2 are relatively high,while the Tl content is relatively low.The δ34S values of Py2 range from-16.6‰ to-4.2 ‰,and Au mainly exists in the form of solid solution(Au+).Py3 has high contents of Sb and Tl,and low contents of W and Bi.The δ34S values of Py3 vary from-25.2‰ to-20.1‰.The gold occurs as structurally bound gold and nanoparticles.The study indicates that the precipitation and enrichment of gold in the Zaozigou gold deposit may be related to water-rock interactions and fluid boiling.The Zaozigou gold deposit should be classified as an orogenic type gold deposit.
NETL
NSTL
万方数据
