山西朔南矿区含煤岩系特征及其沉积环境

Coal-bearing Strata Characteristics and Sedimentary Environment in Shuonan Mining Area, Shanxi

根据山西朔南矿区太原组、山西组岩石类型、丰度及地球化学特征资料分析显示:太原组砂岩丰度平均为42%,泥质岩类丰度平均为29%,砂泥岩比平均为0.64;山西组砂岩丰度平均为62%,泥质岩类丰度平均为24%,砂泥岩比平均为1.3;从太原组—山西组(B)、镓(Ga)、锶(Sr)、钡(Ba)、锰(Mn)、铁(Fe)等元素含量也具有明显的差异。结合含煤岩系沉积旋回分析,认为太原组—山西组沉积环境由海陆交互相过渡为陆相沉积,成煤环境经历了由滨海、潟湖、潮坪—三角洲水下、水上分流河道、分流间湾—曲流河冲积平原的演化过程。

Based on rock type, abundance and geochemical characteristic analytical data, in the Taiyuan Formation, average sandstone abundance is 42%, argillaceous rock 29%, average sand-shale ratio 0.64; in the Shanxi Formation, average sandstone abundance is 62%, argillaceous rock 24%, average sand-shale ratio 1.3. From B, Ga, St, Ba, Mn and Fe elements content in the two formations also have obvious differences. Combined with coal-bearing strata sedimentary cycle analysis, considered that, from Taiyuan Formation to Shanxi Formation, sedimentary environment transiting from marine-terrestrial alternating facies to terrestrial facies, coalforming environment has experienced an evolutional process from littoral, lagoon, tidal flat-delta subaqueous, superaqueous disttibutary channels, interdistributary bay- meandering stream alluvial plain.