鸡西盆地下白垩统城子河组-穆棱组露头砂岩中的黏土矿物成因探讨

对鸡西盆地下白垩统城子河组—穆棱组露头砂岩中的黏土矿物进行了X-衍射分析。研究结果表明,黏土矿物主要由伊利石,高岭石和伊/蒙混层组成,组合可分为高岭石型与伊/蒙混层和伊利石型两种,根据黏土矿物组合判断露头砂岩处于中成岩阶段A期。下白垩统城子河组—穆棱组煤系地层和泥岩成岩过程中析出的有机酸是高岭石型黏土矿物组合发育的重要原因,而沉积相带水动力条件弱导致砂岩渗滤条件的变差则是伊/蒙混层和伊利石型黏土矿物组合形成的原因。

Discussion on origin of clay minerals in outcropped sandstone from Lower Cretaceous Chengzihe Formation and Muling Formation in Jixi Basin

Clay minerals in the outcropped sandstone from Lower Cretaceous Chengzihe Formation and Muling Formation in Jixi Basin were analyzed by X-ray diffraction.The results show that the clay minerals mainly consist of illite,kaolinite and illite/smectite,which can be divided into two types:kaolinite-and illite/smectite types.The outcropped sandstone occurred in middle diagenetic stage-A on the basis of the clay mineral composition.The development factor of the formation of kaolinite type clay mineral is caused mainly by the organic acid from the coal-bearing formation and mudstone during the diagenesis process in Lower Cretaceous Chengzihe Formation and Muling Formation in the Jixi Basin.The weak hydrodynamic force of sedimentary facies made the sandstone leaching condition poor,which is the reason forming the aggregation of clay minerals of the illite/smectite-and illite types.