Stable Isotope and REE Geological and Geochemiscal Characteristics of the Calcite in the Fankou Zinc-Lead Deposit, Guangdong Province, China

The calcite of Fankou zinc-lead desposit was divided into four kinds, the frist three of them were studied with a depth. The frist calcite was unrelated to mineralization (∑REE=8.277×10-6, LREE/HREE=3.866, δEu=0.997, Pb+Zn=5.02× 10-6, δ13CPDB=-1.307‰, δ18OSMOW=15.7‰, 87Sr/86Sr=0.7161); the second calcite in mainly metallogenic stage which was fromed by mineralizing fluids (∑REE=43.624×10-6, LREE/HREE=16.047, δEu=2.284, Pb+Zn=9.065×10-6); the third calcite in late metallogenic stage which was fromed by remaining solution (∑REE=14.731×10-6, LREE/HREE=3.112 δEu=0.705, Pb+Zn=4.84×10-6). The second and third calcites were product fromed by the mineralizing hydrothermal (δ13CPDB=-6‰, δ18OSMOW=18.43‰, 87Sr/86Sr=0.7136). Two types of fluids exsist in Fankou Pb-Zn desposit, the frist fluid fromed the first calcite which comed form formation water, unrelated to mineralization; the second fluid fromed the second and third calcite which comed form deep seated hydrothermal of the mine areas, was mineralizing fluid, the properties of the second fluid changed relative reducing in mainly metallogenic stage into relative oxidizing condition in late metallogenic stage. From the surrounding rock to ore, δ13C and 87Sr/86Sr were gradually deceased of the calcite, but Pb, Zn, Cu, ∑REE and δ18O were gradually increased, these laws is similar to that of Mississippi Valley-type (MVT) deposit, and provide guiding significance for prospecting new ore bodies.