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四川江油马角坝地区石炭系发育良好,化石丰富,是研究四川盆地石炭系的经典地区之一。采用微相分析的方法,根据江油马角坝地区双龙剖面碳酸盐岩的生物组合、颗粒成分、基质类型及其结构等特征,将该地区石炭系划分出11种微相类型。根据微相类型及其组合特征将本区的沉积相划分为4个沉积相带,分别为台地边缘簸选砂滩相/FZ6、开阔台地相/FZ7、局限台地相/FZ8和蒸发台地相/FZ9。根据沉积相带的组合特征可以判断:该地区早石炭世经历了海进—海退—海进旋回,晚石炭世经历了4期短暂波动的海进—海退旋回和两期相对完整的海进—海退旋回。
The Carboniferous in the Maoyaba area of Jiangyou, Sichuan Province is well developed and rich in fossils, and is one of the classic areas for studying the Carboniferous in the Sichuan Basin. Based on the features of the biogenic assemblage, grain composition, matrix type and structure of carbonate rocks in the Shuanglong section in the Jiangyou Majiaba area, the authors use the method of micro-facies analysis to classify the Carboniferous in this area into 11 types of microfacies. The sedimentary facies of this area are divided into four sedimentary facies zones according to the types of microfacies and their assemblage characteristics: sandy beach facies / FZ6, open platform facies / FZ7, restricted platform facies / FZ8 and evaporation platform facies / FZ9. According to the assemblage characteristics of sedimentary facies belt, it can be concluded that the Early Carboniferous in the area underwent seaward-receding-marine cyclebacks, that the Late Carboniferous experienced four transient fluctuation seaward-descending cycles and two relatively intact seas Enter - go back to sea.