Superimposed Mineralization of Dabaoshan Polymetallic Deposit in Guangdong Province:Evidence from Sulfide Re-Os and Rb-Sr Dating and In-Situ Trace Element Analysis
Wang Lei
Wang Xiangdong
Hu Jun
Jin Xinbiao
Zhang Xiong
Tan Juanjuan
Abstract：The Dabaoshan deposit is a large-sized polymetallic deposit within the Qin-Hang Metallogenic Belt,and it is still controversial whether there has been submarine exhalative sedimentation.In this study,we conducted isotopic dating and in-situ elemental analysis of various sulfides in the deposit,having obtained Re-Os isochron age of(366±33)Ma for pyrrhotites and Rb-Sr isochron age of(166.3±2.5)Ma for sphalerite,respectively.The pyrrhotite is characterized by low concentrations of Co and Te,and high concentrations of Ni and Se,with Co/Ni ratios predominantly below 1,indicating a sedimentary origin.Additionally,sphalerite is relatively enriched in elements such as Fe,Mn,Cd,Ga,In,and Sn,exhibiting relatively low Zn/Cd and Cd/Fe ratios,low Co content,and high Sn content,indicating a sedimentary exhalative origin.Generally,the Dabaoshan polymetallic deposit experienced mineralization through Devonian exhalative sedimentation mineralization,followed by Jurassic magmatic-hydrothermal superimposition.The Re-Os isotope system of sulfides remained stable at a mineralization temperature around 400 ℃,preserving the in-situ geochemical signatures of the initial sedimentary processes.The findings provide valuable insights into the genesis of massive sulfide deposits in South China.
Keywords：pyrrhotites Re-Os datingsphalerite Rb-Sr datingin-situ compositionsuperimposed mineralizationDabaoshan polymetallic depositore deposit
Publication Date：2025-07-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：18( 2548-2565 )