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文章通过对含矿目的层及其渗透性的分析、与成矿作用有关的常量和微量元素及部分特征性地球化学指标如有机碳含量、全硫含量、三价铁和二价铁比值的分析,以及流体包裹体成分和物理化学参数的测试,配合铀、铅、碳、氧、硫同位素的分析等方法,综合分析研究区内砂岩型铀矿的地质地球化学基本特征,认为吐哈盆地西南缘砂泥岩互层地层结构完整且延伸稳定,属弱渗透_渗透性地层,对砂岩型铀矿成矿比较有利。据常量和微量元素分析,认为铀成矿存在着明显的地球化学分带性,其中,氧化带以有机碳和全硫(∑S)含量低、Th/U和Fe2O3/FeO及Ra/U比值高为特征;过渡带(成矿带)以Th/U比值低、∑S、Mo、Re含量高为特征;还原带则以明显的低Fe2O3/FeO、Ra/U比值,高有机碳含量为其特征。其他微量元素如Cu、Pb、Zn、Cr、Co、Ni、Zr等及稀土元素在成矿过程中并未得到明显富集。经对相关岩石的铀_镭平衡、气液包裹体及相关同位素的研究,认为铀成矿具有多期次、年代新且集中于第三纪的特点;含矿目的层煤成气提供了成矿所需的还原环境;成矿作用铀源主要来自于含矿目的层本身;铀成矿古流体属低温浅成热液且主要来源于大气降水。
Based on the analysis of the ore-bearing strata and their permeability, the analysis of the constants and trace elements related to metallogenesis and some characteristic geochemical indicators such as organic carbon content, total sulfur content, ferric iron and ferrous iron ratio , And the fluid inclusions composition and physical and chemical parameters of the test, with uranium, lead, carbon, oxygen, sulfur isotope analysis methods, comprehensive analysis of the sandstone-type uranium deposits in the geology and geochemistry basic characteristics that the Turpan-Hami basin southwest The interbedded sandstones and mudstones are complete and stable in extension and belong to the weak permeability and permeable formations, which are favorable to the ore-forming of sandstone-type uranium deposits. According to the analysis of macroreticula and trace elements, there is obvious geochemical zonation in uranium mineralization. The oxidation zone is characterized by low content of organic carbon and total sulfur (ΣS), Th / U and Fe2O3 / FeO and Ra / U ratio High, the transition zone (metallogenic belt) is characterized by low Th / U ratio and high content of ΣS, Mo and Re; while the reduction zone is characterized by low Fe2O3 / FeO, Ra / U ratio and high organic carbon Its characteristics. Other trace elements such as Cu, Pb, Zn, Cr, Co, Ni, Zr and rare earth elements have not been significantly enriched in the mineralization process. Through the study of uranium-radium balance, gas-liquid inclusions and related isotopes of related rocks, it is considered that uranium mineralization has the characteristics of multi-period, new age and concentrated in the Tertiary; The metallogenic uranium source mainly comes from the ore-bearing target layer itself. The uranium metallogenic paleo-fluid belongs to the low-temperature epithermal and mainly comes from the atmospheric precipitation.