Geological Characteristics And Prospecting Perspective Of Fozichong Pb-Zn Ore Field, Guangxi

This paper sum up the elements of ore type, mineral composition, rock alteration and mineralization of the times of Fozichong lead-zinc deposits, on the basis of large numbers of field investigation and indoor test analysis and synthesize information.The zircons of biotite monzogranite and granite porphyry at Fozichong Pb-Zn deposit yield a SHRIMP U-Pb age of (450±6) Ma, (96.7±1.4) Ma and (95.8±1.2) Ma. Combined with the rare earth and trace element characteristics of the igneous rocks in this area, we got that the granidiorite, granite porphyry and dacite porphyry were formed by the magma differentitation of the same magma source and epoch, except the biotite adamellite.The ore body of Fozichong lead-zinc deposits can be divided into two kinds of layered ore bodies and massive ore bodies. In addition to the ore bodies produced in the fracture zone, the REE of most layered ore bodies are basically the same to the region's massive ore body, massive green rocks, magmatic rocks, A small amount of REE of layered ore body show moderate negative Eu anomaly, with some similar characteristics of layered green rocks, Shows the differences of geophysical and chemical conditions of ore-forming process. The fluid inclusions in Fuzichong Deposit are mainly H2O-NaCl liquid inclusions with low salinity and low density. These inclusions mainly homogenize at temperatures range from 110℃to 190℃or from 340℃to 400℃. Sulfur isotopic investigations of sphalerite, galenite and chalcopyrite demonstrate thatδ34S values of Fuzichong Pb-Zn deposit distribute like a tower clock which are concentrated in the vicinity of 0‰, suggesting a relatively homogeneous and deep material supply. Ore lead isotope model age is 136Ma, most of its dots fall on the Pb isotope evolution map near the orogen curve and the upper crust curve, and Pb isotope of the Pb ore sample was linearly Distribution, indicate the Pb source of Fuzichong ore field relatively simple, mainly closely related with Mesozoic magmatic rocks. To sum up the above arguments, Fozichong Pb-Zn deposit is an epithermal deposit closely related to Yanshanian magmatism.According to the study on its mineral compositions, textures and structures, wall rock alteration and rare earth elements of the main ore-bearing rocks, we found the genesis of the main ore-bearing rocks, which is green rocks, and then summed up the control conditions of the green rocks. Combined with the three-dimensional map of the orebodies, a good prospects of mineral exploration in deep mine and south of mine field is suggested.