【摘要】 <正> 上二叠统合山组是桂中地区主要含煤地层,它在马滩一带沿红水河出露特别完整。合山组是较为少见的局限台地碳酸盐岩型含煤建造,研究它的物质成分、沉积结构和构造、生物化石、沉积相类型、垂向层序及沉积模式等,为探索含煤建造的形成条件和分布规律提供了必要资料。这一研究课题,无论在沉积学理论上或成煤理论上都有重要意义。笔者先后于62年、78—81年多次到野外进行观察,82年又补充了一定的野外工作。其中78—81年广西150煤炭勘探队参加了野外工作。工作过程中,广西合山矿务局和董家国工更多还原

【Abstract】 The Upper Permian Heshan formation, the most important coal-bearing strata in central Guangxi, is a main source of industrial coal.The Heshan formation is a coal-bearing formation of carbonatite type of restricted platform. It belongs to a special type.To study it in detail is of great significance to sedimentology, the theory of coal-formation and to the industrial production.The chief characteristics of the coal-bearing formation of this type are as follows: 1. More than 85% of the total formation is composed of limestones, predominantly organic limestone, bioclastic limestone and reef limestone.2. The dominant facies are mainly restricted subtidal, intertidal and reef facies.3. Biological fossils and bioclasts of various genera and species are exceedingly rich, chiefly Chlorophyta, Fusulina and Spongia.4. Organic reefs ( especially the Sponge reefs ) develop well. They occur chiefly on the top and ia the middle-lower parts of the section.5. The whole formation consists of marine facies ( including coal seams ) . There are no continental sediments. It can also be proved by the results of trace element, DTA, X-ray diffraction and electron microscope analyses of the coal seams and their top, bottom and slooms.The coal seams formed in the "peat-flat" environment, which is different from the common coal-forming swamp. The differences are as follows:1. It is situated mainl yat the intertidal zone, but not in the subaeral envi-ironment.2. It is situated on the flat behind the reef in the calm, shallow environment. The organic reef serves as a barrier.3. The original coal-forming substance is perhaps some halophytes, quite similar to mangroves growing in the recent tropical and subtropical littoral zone, but it is not a fresh water terrigenous plant.4. The coal seams formed in the "peat-flat" are characterized by extremely high ash and sulphur. The "peat-flat" is a special environment for the formation of coal. Sometimes it developed from the tidal channel distributed on the intertidal flat. For example, the bottom of the upper layer of the 4th coal seam workable throughout the Heshan coal field, in some places, is the tidal channel originally composed of calcirudite.The organic reef (probably belonging to the biostrome accordingto their morphology ) is one of the characteristics of coal-bearing formation of carbonatite type of restricted platform.The formation and distribution of coal seams are influenced and controlled directly by their presence. The calm, shallow water environment of back-reef is favourable for the formation of coal seam. In general, the longer the interval of reef-forming stage and the better the reef-flat develops, the more favourable for the formation of coal seams.更多还原