The large scale Pb-Zn-Ag deposit in the northern Neixiang County in Henan Province is found in the Erlangping Terrain which is on the north side of Zhu Xia fault in North Qinling orogenic belt, which formed in deterioration volcano sediment of the back arc environment during the Late Proterozoic Early Paleozoic.Nearly 100 mineral veins have been found, most of which are filled in fault structure of vertical orogenic belt and present layered and bedded single veins, in which the large scale Y1, Y3, Y6, Y10 and Z2 are typical. We select the sphalerite mineral of Y1, Y3, Y6, and Z2 together with galena mineral of Y10 to test S isotope, and δ34SV CDT ranges from 1.89‰ to 7.34‰, which indicating that sulfur is mainly from the thermo chemical sulfate reduction of Paleozoic marine host strata; Pb isotope from galena shows that 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb are 18.229,4-18.384,5, 15.608,9-15.643,4 and 38.516,0-38.715,2, respectively, μ value is between 9.50 and 9.55,and ω value is between 37.45 and 38.35, all above shows that metal ore sources from Paleozoic metamorphic volcano sedimentary host strata.Studies show that the ore sources of Pb-Zn-Ag deposit in the northern Neixiang County, may come from the Qinling Group and Erlangping Terrain.
