大兴井田4#煤层砂岩砾岩体特征及成因分析

Analysing characteristic and reason of sandstones and conglomerater body in 4~# coal-seam of Daxing well-field

运用沉积学理论，通过对铁法煤田大兴井田4#煤层中发育的砂岩、砾岩体的研究，指出它们均为河道沉积产物，并从中识别出了聚煤早期河道正常沉积、聚煤期后河道水携物与坍塌物混积和河道泥石流沉积三种成因类型，论述了它们各自的岩相和空间发育特征，这将有益于揭示其平面分布规律，为进一步指导采场的科学设计和修订提供了基础。

Applying sedimetological theory and through studying the sandstones and conglomerater body, which grow in 4# coalseam of Daxing well-field, it is pointed out that they are channel deposits, and distinguished three genetic types that they are normal stream channel deposit in the early coal-forming period, hybrid deposit of debris in the stream and talus after coal-forming period, and channel debris flow deposit. It formulated that their lithofacies and spatial growth characteristic respectively. It is beneficent to discover their plain distributary regulations, and furthermore, it provided the foundation for further scientific design and amendment of slope.