| Molybdenum deposit formed in Indosinian Period and Yanshan in Qinling is the research object in this thesis. Based on the comprehensive analysis of the predecessors’ research achievements, cooectiong and Identification of rock ore samples, with the aid of modern geology experimental analysis methods, comparative study on molybdenum granite geological characteristics of rock mass(output characteristics, geochemical characteristics of rock mass, rock mass) and molybdenum deposit geological characteristics of typical(mine geological characteristics, geological characteristics of ore bodies, ore deposit formation characteristics).The exposed area of molybdenum granite formed in Yanshan Period in qinling area is less than1 km2.And they are near the existing related to the causes of large batholith. However, the indo-chinese epoch molybdenum granite rock mass general scale is large, generally a few hundred square kilometers. Molybdenum in yanshan period granite rock mass is ore body, orebody mainly exist in the rock mass and the inner and outer contact zone, a small amount of occurrence in rock mass surrounding rock. Indo-chinese epoch molybdenum body within the rock, but there is also a part of ore bodies distribution in the outer contact zone of rock mass.Ore-bearing granite in Qinling mountain area has high silicon molybdenum rock, rich potassium, calcium magnesium iron poor characteristics, belongs to the alkali granite series, further divided into potassium XuanYan- high potassium alkaline series, mostly for aluminium oversaturated rock. All the content of alkali w(Na2O + K2O) is very high. And these granite have the characteristics that K2 O is richer than Na2 O. SiO2 and Fe2O3, TiO2, CaO, P2O5 present a weak negative correlation. Yanshan epoch formed molybdenum mainly exist in granite(porphyry) of rock.But the indo-chinese epoch formed molybdenum mainly occurs in granite porphyry. Related to the ore-forming magmatic intrusion activities tend to occur in later period.Qinling region containing molybdenum in the rock mass have strong enrichment of Mo element, with high field strength elements common enrichment,and large ion lithophile elements most losses. ∑REE variation in Molybdenum-bearing granitoids range is very big, but all have the light rare earth concentration, heavy rare earth losses, elements of Eu negative anomaly characteristics. The chondrite-normalized REE patterns exhibit a gently right-dipping V-type curve with a severe depletion in Eu. According to the δ(Eu) and Sr,molybdenum all belong to the crust-mantle mixed dye type granite rock mass.Molybdenum ore body in Qinling region is distributied by metallogenic period of transtensional fault and joint action control obviously.The molybdenum ore has similar characteristics. Ore minerals and gangue minerals content are the same, with porphyritic structure, vein and vein and disseminated structure. But there are differences on metallogenic mode, namely Pan He molybdenum mineralization is given priority to with filling, and poplar ditch molybdenum mineralization is given priority to with metasomatism. There are the silicified alteration belt, green rock lithification belt(chloritization, epidotization) and black mica tape around the rock mass. However, due to individual differences, cause the missing potassium in Pan He molybdenum belt is more lithification carbonate belt. Poplar ditch wall rock alterations in molybdenum belt scale are distributed in surrounding rock band there is a fundamental alteration belt. Although, two orebody formed in different age. Intermediate-acid magmatic invades the formation along the regional fracture structure, with the change of the temperature pressure condition. Reactting with surrounding rock causing the ore-forming substances precipitation, formed ore bodies. |
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