Geochemical Characteristics And Genetic Mechanism Of Jinchangliang Au Deposit In Aohan Banner, Inner Mongolia

Jinchangliang gold deposit is in the ore concentration area, where is a idealmetallogenic environment in Inner Mongolia Xingan block and the northern part ofNorth China plate interchange location, so many gold deposits in the area. It’snorthern boundary is nearly EW Chifeng-Kaiyuan super lithospheric rupture, the westboundary is NE-NNE Linjiadi-Siguanyingzi fracture, and the southeast is NEChengde-Beipiao deep fault. In the study area, faults are developed and magmaticactivity is frequent, the zone has a excellent mineralization condition. In this paper,we carry out a research on the regional metallogenic background, geological andgeochemical characteristics, deposit genesis and mechanism of the Jinchangliang golddeposit. Which can provide a very important guiding significance to prospect andexplor new types of mineralization and new resources position, especially in thenorthern of Chifeng-Kaiyuan deep rupture.The study of deposit geological characteristics shows that host rocks of theinclusive gold deposit is Archean metamorphic rocks in Wulashan group. Mainlyinclude biotite plagioclase gneiss, biotite hornblende plagioclase gneiss, amphibolitegneiss and migmatite gneiss variety. There is EW trending fault in the north of Mine,which limit the fine adamellite. In the contact area, we can see structure fracturedzones, occasionally chlorite, silicification and other alteration phenomena. Faultsdeveloped, mainly to the NW and near EW direction, output veins strictly controlledby faults. The form of ore is vein, lenticular, lenticular and so on. Mineralizationoccurs mainly in quartz vein and silicified wall rocks, and quartz vein mineralization is strongest, from the vein to outward, mineralized gradually weakening. Metallicminerals are chalcopyrite, pyrite, silver and gold mines, bornite, magnetite, stibnite.Wall-rock alteration types are phyllic, silicification, chlorite, carbonate of etc., is a setof gold mineralization associated with the low-temperature alteration minerals.Fluid inclusion studies indicate that Jinchangliang gold deposit of fluidinclusions in quartz are gas-liquid two-phase. The ratio of gas and liquid is generallyfrom10to30percent, mostly concentrated in the10to15percent. Salinity range ofore-forming fluids of1.05~8.14wt%(NaCl), the density is between0.856with0.986g/cm3, it shows the characteristics of low salinity and density. Uniformtemperature of138.3~223.2℃, mineralization pressure5.32~11.1Mpa, mineralizationdepth of0.52~1.11Km, with a low temperature epithermal mineralizationcharacteristics. H-O isotope studies have shown that which has a deep hydrothermalore characteristics, the main ore-forming fluids in magmatic mineralization of water,and contains a small amount of atmospheric water. S isotope studies show that asminerals from the mantle or deep crust.Late Triassic adamellite rock is related to the Jinchangliang gold deposit, thestudy of chemistry and geochemistry indicate that the rock belongs to high aluminum,high-K calc-alkaline rocks. In the R1-R2tectonic discrimination diagram, the twogranite samples projector main point fall in the late orogenic granite area. GraniteTa-Yb tectonic discrimination diagrams mainly located in the same collision-Lateorogenic granite area. Therefore, Late Triassic adamellite is land-land late collisionorogeny produced "S" type granite, It illustrate the Late Triassic collision orogeny andKorean ancient Siberia between the plates basically ended.In general, our study indicated that the the plant genetic type of Jinchanglianggold deposit belonging to the beam of light into the low Yanshan orogenic golddeposit.