【摘要】：小包莊鐵礦位于長(zhǎng)江中下游成礦帶廬樅火山巖盆地中,是近幾年來(lái)新發(fā)現(xiàn)的又一大型玢巖型鐵礦床。小包莊鐵礦在空間上位于羅河鐵礦的下部,形成了兩個(gè)礦床上下疊覆的模式。本文以小包莊鐵礦為主要研究對(duì)象,以羅河鐵礦為補(bǔ)充,在收集整理和總結(jié)了前人研究的基礎(chǔ)上,進(jìn)行了詳細(xì)的野外地質(zhì)調(diào)查,通過巖相學(xué)、礦相學(xué)、電子探針分析、主微量元素分析、硫同位素分析以及流體包裹體研究,探討了小包莊鐵礦的成因、成礦物質(zhì)來(lái)源、成礦流體的演化以及小包莊鐵礦與羅河鐵礦的關(guān)系。測(cè)試結(jié)果顯示,小包莊鐵礦磁鐵礦礦石中不同成礦階段形成的黃鐵礦、硬石膏的δ34S值異常高,黃鐵礦的δ34S值集中在6‰~15‰的范圍內(nèi),硬石膏的δ34S值集中在16‰~24‰的范圍內(nèi),并且隨著成礦期次由早到晚、深度由深到淺,黃鐵礦、硬石膏的δ34S值逐漸降低,同時(shí)測(cè)得小包莊鐵礦下部三疊紀(jì)東馬鞍山組膏巖層的δ34S值為30.1‰,反映了小包鐵礦中的硫有膏鹽層的加入。包裹體測(cè)溫結(jié)果表明,小包莊鐵礦透輝石-磁鐵礦-硬石膏化蝕變階段、綠簾石化蝕變階段、碳酸鹽-硬石膏-黃鐵礦化蝕變階段和硬石膏-石英-黃鐵礦化蝕變階段的成礦流體溫度分布區(qū)間分別為326~496℃、259~317℃、178~280℃和107~189℃,鹽度分布區(qū)間分別為14%~21%NaCl eqv、11%~20%NaCleqv、6%~16%NaCleqv、2%~13%NaCleqv,成礦流體經(jīng)歷了從高溫高鹽度向低溫低鹽度演化的過程。從成礦巖體、礦體特征、礦石特征、蝕變分帶特征以及成礦溫度等方面與羅河鐵礦進(jìn)行對(duì)比表明,小包莊鐵礦與羅河鐵礦應(yīng)為兩個(gè)同一類型的獨(dú)立礦床,其在空間上上下疊覆的模式可能是由閃長(zhǎng)質(zhì)巖漿在不同深度侵位而形成的。
[Abstract]:Xiaobuzhuang iron deposit is located in the Luzong volcanic basin of the middle and lower reaches of the Yangtze River metallogenic belt. It is another large porphyrite type iron deposit newly discovered in recent years. Xiaobuzhuang iron deposit is located in the lower part of Luohe iron deposit in space, forming the superimposed model of two deposits. In this paper, taking Xiaobuzhuang Iron Mine as the main research object and Luohe Iron Mine as the supplement, on the basis of collecting, arranging and summarizing the previous studies, detailed field geological survey was carried out, and the petrographic, mineralogical and electron probe analysis were carried out. The main trace element analysis, sulfur isotope analysis and fluid inclusion study, the origin of Xiaobaozhuang iron deposit, the origin of ore-forming material, the evolution of ore-forming fluid and the relationship between Xiaobuzhuang iron deposit and Luohe Iron Mine are discussed. The test results show that the 未 34S value of anhydrite is unusually high, the 未 34S value of pyrite is concentrated in the range of 6 鈥，

本文編號(hào)：2240129