| Copper-milybdenum ore zone locates in Manchouli City southwest22kilometer department, the work area scope schedule is about 9.54squarekilometer, administrative division belongs to Mongoliamunicipality Xinbarhufight county geographical coordinates:eastlongitude 117°14ˊ~117° 22ˊ;north lantitude 49° 22ˊ~49° 30ˊ from Manchouli City to mining area therehave got three grasslandthoroughfaresand railways gone to all parts of thecountry, traffickingis convenient. The studied area lies in the southeast exterior margin of Siberianplate. Itbelongs to the transitional crust tectonic province betweenSiberian plate and Sino-Korean plate. There are antique fold baseformed with Proterzoic and Cambrian Era in crustal structure developedhistory. Cracking occurred after orogenic movement in Caledon.Geosynclinal deposits construst in the Devonian to theCarboniferous-Permian Period developed at late Paleozoic. In contrastto Mongolia and Russia materials, it dues to the outer Baikal fold scope,whose boundary is Erguna-Hulun deep rupture in the fold belt inDahingganling. This fracture belt is a very important tectonic belt.(Zhao suggests that it is a joined tectonics between Siberia Plate andNorth Plate.) It joined the deep fracture of mid-Mongolia in south,side and Ehuocike in north side. Derpugan fracture which controlsregion mineralization is its branch. With systemly collection and predecessors' research works, theauthor summarized the tectonic setting, ore-bearing character,deposit geology and geochemical character of Wunugetucopper-milybdenum deposit and explored metallogenic origin and builtmodels according to the field and other delicate studies. Combined withcurrent new porphyry theory, the author suggested that Wunugetucopper-milybdenum ore possesses adakite character for the first time.It contributes widen clues for prospecting. The studied results areas follows: Wunugetu copper-milybdenum locates in the west of Erguna-Hulundeep fracture, the communicated complex section between outer Baikaland Dahingganling geosynclinal folded system. The deposit occurredMesozosic lava strap bulging area. The strata in region are DevonianWunur Group and Jurassic Shangkuli Group etc. The most of the formerare sand slate andesite and the latter are basaltic andesite, dacite,rhyolite and clastic lava.Mid-acid magma active intensively in region. The intensiveactivity and widest distribution are famous for dacite porphyry,quarts porphyry, monzograntic porphyry and granite porphyryetc.Copper-milybdenum minerali-zation is associated with plagioclasegranite. Ore-beating bodies are shallow sub-plagioclase granite andgranite porphyry. It is in the volcanic aisle. Granite porphyry exsitsin remains in breccia rock ripe. The age of the ore-bearing is 138Ma.Ore-bearing bodies have intensive alteration and arecharacteristiced in departed belts. Quartz-Kalium alteration mostlygrown in the centre of rock bodies altered minerals composed of quartz,potash feldspar, sericite grade etc, parts of them accompanied withpaulopost alteration superposd damourite, illite grade;quartz-sericite-damourite belt lay out side of quartz-potash belt, theshape was the same with quartz-potash belt and occurred in tiltbarrel,which was characteristic in sericite+damourite>30%,illite-damourite belt appeared exterior margin, typical character wasillite+damourite>30%. The three alteration zones above mentioneddistributed in subconcentric ring, under F7 fault movement influence,formed two half ring, constituted south and north two ore blocks.Judging from character of major elements, the alteration ofstudied area were charactered in displaced type, centrosymmetry seriesand surficial shape in K+,Si4+, OH-. With the alteration intensive K+,Si4+, OH-contents which carried in and Na+, A13+, Ca2+, Mg2+, Fe2+contents which took out increased. K and Na, Si, A1 showed negativecorreation;short ofpropylite alteration.Suffering from Copper-Milybdenum ore bodies F7 fold impacted formsouth and north two ore belts.Mining area altogether proved copper oreshell 33 strip, Mo minerals shell 13 strip. Cu-Mo ore bodies conditionshowed tingwise (stagger showed for horseshoe). The whole trendnortheast, incline NW, inclined angle steeper (60°~85°), loop length1300~2550m, depth extent 150~650m,thickness 350m.Most ore mineral for chalcopyrite, molybdenite, pyrite andmagnetite, secondly for galena, blende, bitreous copper, hematiteand/or cuprttrn, molyb-denic secondary mineral. Ore structure werecharactered in veinlet, disseminated-veinlet, disseminated. Oretexture include acinose structure, metasomatic texture, containstructure, breakdown of solid solution structure, foliated texture andrimmed texture grade. The main metallogenic element in ore for Cu(0.2%~0.6%, supreme 2.08%), Mo (0.02%~0.06%, supreme 0.95%),accompanied elements have Au, Ag, Re, In, Se, Bi, Pb, Zn etc, whichRe, Ag, Au approved complex utilization.Rock (mine) anlitical resulting displayed that the magmatite ofthe studied area belonged to cala-alki aluminum suprestatured sties,which showed the same magma source evolution. They all formed inorogenic environment. The rare earth element of rocks (mines) impliedthat ore bodies and surround rock's REE transformation possessedcomplementarity in the course of hydrothermal alteration. Depleted Euhas indicated meaning to Cu-Mo ore alteration. The geochemistrycharacter of ore bodies indicated adakite rock's property. The oresulfur, hydrogen, oxygen istope characters reflected that mineralsubstances, mine source were associated with magmatic activity.Ore-forming fluid's research reflect Mo formational temperature were317~455℃, averaged in 380℃;Cu formational temperature were 324~410℃, averaged in 364℃. Ore-forming fluid salinity were 9~14wt%, whichsupreme reached 42~68wt%. Different alteration and ore belt, thetemperature, salinity, density, ratio of gas and liuid of ore-forming,all of them indicate Wunugetu mountain Cu-Mo deposits arerepresentative porphyry types ore deposits and based on those we setup metal-logenic model. The result of research indicate secondaryhypabyssal plagioclass granite porphyry, intensive zonal alterationand depleted in Eu, can look as prospected symbol of porphyry Cu-Modeposit in this area.
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