C, O Isotope and REE Geochemistry of the Hydrothermal Calcites from the Tianqiao Pb-Zn Ore Deposit in NW Guizhou Province, China
摘要
///Hydrothermal calcites from the Tianqiao Pb-Zn ore deposit, NW Guizhou Province, China, were analyzed using Continuous Flow Mass Spectrometry and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for their carbon and oxygen isotope and rare earth elements (REE) compositions. The results show that the C and O isotopic compositions of the hydrothermal calcites are relatively homogeneous, and samples from different elevations show similar C and O isotopic compositions. Comparing the host rocks, unaltered rocks, and altered rocks with the hydrothermal calcites regarding C and O isotopic compositions and REE patterns, the authors believe that the ore-forming fluids were mixture of multiple source fluids, within which the C and REE were mainly sourced from carbonate wall-rocks, the sulfur from the thermo-chemical sulfate reduction of sulfates in the sedimentary strata, and the metamorphic water from underlying basement-rocks such as Kunyang Group, and affected by meteoric water.