Study On Geological Characteristics And Genesis Of Mengku Iron Deposit, Fuyun County, Xinjiang

Mengku iron Deposit is located in Fuyun County, Xinjiang Uygur AutonmousRegion. It distance Fuyun County North West linear distance70km. The geotectonicposition is Siberia plate in Late Paleozoic active continental margin of South Altai.Mengku iron deposit belongs to the southern margin of Altai metallogenic belt. Themetallogenic belt found in a large number of deposit,such as,Ashele copper-lead-zincdeposit,Keyinbulake copper-zinc deposit,Tiemuerte iron deposit,Abagong iron-lead-zincdeposit and Keketale lead-zinc deposit et. This area has a good regional metallogenicconditionsThe main formation of mine are Silurian and Devonian formation. Ore bodiesmainly occur at Kangbutiebao Formation， whose main rock types consists ofleucogranulite, granulitite, amphibolite, et. The protolisith recovery display aset ofmarine volcano rocks.Mine area development fold structure and fault structure, Mengkuiron deposit is mainly produced in toward NW tiemuxiaergun secondary closedsyncline.The late strong compression on NE-SW dirction,cause the ore bodies continuouselongated along the strike,while vertical discontinuous distribution, shows elongated evenpull off the stratiform, lenticular nearly parallel to the rock distribution. The main ore bodyare strictly controlled by the formation control, with the syngenetic sedimentarycharacteristics.The ore construct massive structure, disseminated structure and banded structure.Metallic minerals are magnetite, followed by maghemite, pyrite, pyrrhotite, chalcopyrite, limonite, hematite and small amounts of marcasite, bornite, natural platinum.Non-metallicmineral diopside, amphibole, feldspar, quartz, followed by biotite, epidote, garnet, calciteand a small amount of sphene, zircon and so on.Mengku iron deposit experienced three mineralization, marine volcano-sedimentarymineralization period (hydrothermal exhalative mineralization related to volcano action),related to the skarn mineralization and metamorphism and deformation trans formationstage. Deposit because of later metamorphism and deformation, which makes the oremorphological change. Manifested as continuous elongated along the strike,while verticaldiscontinuous distribution, eventually formed like a layer of non-layer pulse-likenon-pulse characteristics. Hydrothermal exhalative mineralization uniform fluidtemperature range of127.3~275.3℃,salinity range of4.0~10.9wt%NaCl.eqv,anddensityrange of0.81~0.98g/cm~3.The sulfur isotopic characteristics of the main source of endogenous deepcharacteristics, but not completely consistent with meteorite sulfur compounds. Mengkuiron sulfur from deep and mixed with seawater sulfate in heavy sulfur. Hydrogen andoxygen isotope values in the hydrogen-oxygen isotope plot is located between the seaand the magmatic water. It implied ore-forming fluids is the result of mixing of seawaterand magmatic water and atmospheric precipitation.Comprehensive analysis of Mengku iron deposit has gone through threemineralization period, respectively, the marine volcanic-sedimentary mineralizationperiod (exhalative mineralization period), related to the skarnmineralization and regionalmetamorphism mineralization period. In which exhalative mineralization formed thewestern Mengku Iron’s largest and most industrial significance orebody.