【摘要】 在东昆仑小南川中-新元古界万保沟群(Pt2-3W)的大理岩地层中发现磁铁矿石,大理岩上下地层的岩性为灰绿色板岩,在野外,磁铁矿层最宽50cm,最窄为10~20cm,单层或多层产状,局部地段已被变形拉长成透镜状,沿倾向和走向延伸不定。该条带状磁铁矿石即条带状含铁建造,矿石为浸染条带状构造,由致密与浸染相间的条带组成。光谱半定量检测分析结果显示,矿石除含金属元素Fe外,还具少量金属元素Cu、V、Zn、Al、Mg、Mn、Ti等,化学分析结果 TFe为50.10%,为富磁铁矿石。磁铁矿野外产出的地质特征、围岩、矿石特征和上述检测分析结果表明,磁铁矿应是在滨浅海的古地理环境中,有火山物质加入,在动荡的条件下沉积而成的。根据该富磁铁矿石产出的万保沟群地层和大理岩特征,结合地磁异常,下一步东昆仑地区磁铁矿的找矿工作,可在西段布伦台南部、中段小南川、东段香日德南塔妥煤矿地区来开展。更多还原

【Abstract】 Magnetite ore was found in marble strata of Mesoproterozoic-Neoproterozoic Wanbaogou Group(Pt2-3W) in Xiaonanchuan area of East Kunlun Mountains,and the overlying and underlying strata of the marble are grayish green slates.In the field,the broadest magnetite ore beds are 50cm in width whereas the narrowest ones are only 10-20cm,and the ore beds occur in the forms of single or multilayered beds.Some of them have been elongated into lenticular from and assume irregular extensions along the dip and strike.The banded magnetite ores,called "banded iron formations"(BIFs),have impregnation and band structure and consist of alternate compact layer and impregnation band.Semiquantitative spectrographic analysis reveals that there exist small amounts of Cu,V,Zn,Al,Mg,Mn,Ti,besides Fe,and chemical analysis and X-ray diffraction analysis shows that TFe is 50.10%,suggesting magnetite-rich ore.Geological characteristics,wall rocks,ore structures and experimental analysis of the magnetite ore shows that the magnetite ore should have been formed in the coastal and shallow sea environment with the addition of volcanic materials under the turbulence aggradation condition.According to the characteristics of the magnetite ore in Wanbaogou Group strata and the marble,in combination with the geomagnetic anomalies,the authors hold that the next step of magnetite ore exploration in East Kunlun region should be carried out in south Buluntai area of the west segment,Xiaonanchuan area of the middle segmentt,Xiangride area around the Tatuo coal mine of the east segment.更多还原