河南大冶矿区晚石炭世岩相古地理特征及铝土矿找矿方向

河南大冶铝土矿区晚石炭世早期处于古岛高地之间的滨岸潟湖沉积环境。中奥陶统以后,经历了160Ma风化剥蚀,在碳酸盐岩的侵蚀面上发育了钙红土铁、铝、硅风化壳。晚石炭世本溪期,海侵作用使矿区所在区域变为滨岸潟湖沉积环境,沉积相出现滨湖相、浅滩相、浅湖相、浅海相、滨岸沼泽相等5种;晚石炭世晚期形成海陆交互相的复理石沉积建造,将早期形成的铝土矿完整保存下来。今后铝土矿的找矿工作应重点放在浅滩-浅湖岩相带、含铝岩系相序发育相对完全的地段、含铝岩系厚度大且稳定的区段,并注意含铝岩系的表生富集作用。

Late Carboniferous lithofacies palaeogeogrphic feature of Daye bauxite mine area in Dengfeng county, Henan province and the prospecting direction

Lithofacies paleogeographic sedimentary environment of Daye bauxite mine area in Dengfeng county, Henan province was coastal lagoon between ancient island heights in the Early period of Late Carboniferous Epoch. During weathering and erosion for 160 Ma Fe-Al-Si-bearing calcareous lateritic crust were formed at the erosion surface of carbonate rocks. Transgression of Benxi stage of Late Carboniferous Epoch brought the mine area under coastal lagoon environment where are developed shore lake, shoal, shallow lake, shallow sea and shore swamp sedimentary facies. In the late period of Late Carboniferous Epoch flysch sedimentary formation of paralic facies deposited and buried the above mentioned bauxite deposit. Bauxite ore prospecting in future should target at shoal-shallow lake facies (belt), the completely developed aluminiferous rock sequence, the thick and stable aluminiferous rock sequence. In addition, attention should be paid to supergene enrichment of the aluminiferous rock sequence.