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研究表明,西天山大中型富铁矿床主要赋存于伊犁石炭纪弧后盆地,铁的成矿应与早石炭世海相火山诱发的熔流体喷溢与热液交代密切相关,且盆地建造制约矿化类型及其分布.区域航磁测量获得了近东西走向的高磁异常带和北西向、东西向的低磁异常带相间分布的格局,磁场梯度变化较大,客观反映了不同构造单元中地壳物质组分的明显差异,且很好地反映了阿吾拉勒铁矿带的区域分布特点.赋存于大哈拉军山组熔岩-火山碎屑岩建造中的铁矿床主要定位于火山机构断裂系中,大多与容矿火山岩系呈不协和接触关系,其产状取决于矿床在火山机构/火山穹窿中所处的具体位置,成矿物质主要来源于火山晚期高温熔流体和岩浆热液;而赋存于伊什基里克组的铁矿床主要属于化学沉积铁矿,其定位和规模主要受控于水下沉积洼地的古地貌特征,因而它们大多与上下盘地层呈整合接触关系.因此,伊犁盆地石炭纪海相火山岩建造与海相火山-沉积建造之间的差异性,很可能是控制不同类型矿床形成与定位的第一要素.
The study shows that the large and medium-sized iron-rich ore deposits in western Tianshan occur mainly in the Yili Carboniferous backarc basin. The metallogenesis of iron should be closely related to the melt inflow and hydrothermal metasomatic alteration induced by the Early Carboniferous marine volcano, and the basin construction Which restricts the type and distribution of mineralization.The regional aeromagnetic surveys obtain the patterns of high magnetic anomaly near the east-west direction and the distribution of low-magnetic anomaly bands in the northwest and east-west directions. The gradient of the magnetic field changes greatly, which objectively reflects the different structural units The difference of material composition in the middle crust, and well reflect the regional distribution characteristics of the Uwulal iron ore belt.The iron deposits in lava-pyroclastic rocks in the Dahalajushan Formation are mainly located in the Most of volcanic fault systems are in non-contact with volcanic rocks of volcanic origin, and their occurrence depends on the specific location of the deposit in volcanic structures / volcanic domes. The ore-forming materials are mainly derived from late volcanic fluid and magma Hydrothermal. However, the iron deposits hosted in Ishikilike Formation belong to chemical sedimentary iron ores. Their location and scale are mainly controlled by the paleogeomorphology of underwater sedimentary depressions. Therefore, most of them are related to the upper and lower disc formations Therefore, the differences between the volcanic rocks of the Carboniferous in the Ili basin and the marine volcano-sedimentary structures are likely to be the first element to control the formation and location of different types of deposits.