铝土岩差异性淋滤模式及古环境分析:以鄂尔多斯盆地陇东地区为例OA北大核心CSTPCD

In order to study the leaching characteristics of bauxite in Ordos Basin and explore the paleo⁃environmental basis for its development,this paper selected Taiyuan Formation bauxite in Longdong area as the research object and analyzed the leaching model and paleo⁃environmental basis of bauxite in North China plate through microscopic observation and combining with the lithology characteristics.The results show that the physical properties of bauxite rock in the study area are greatly improved under the action of underground water leaching.The leaching dissolution diagenesis of bauxite rock has undergone three stages of deposition,supergene and burial,and has a three⁃stage differential leaching dissolution diagenesis model in the vertical direction,and the central part is most affected by leaching transformation.The favorable factors for the formation of bauxite in North China platform are the coupling of warm tropical climate,paleo⁃uplift slope area,paleo⁃karst landform and alternating rise and fall of sea level.Therefore,the bauxite in Ordos Basin has a good paleo⁃environment and has been found in many parts of the basin as far as the North China plate.The bauxite with good reservoir quality is mostly formed in the relatively high part of the structure,and the slope is a favorable development area.