龙永煤田早二叠世童子岩组第三段聚煤古地理分析

Analysis of Accumulation Coal Palaeogeography for Tongziyan Third Section of Early Permian in Longyong Coalfield

通过龙永煤田古地理分析表明:童子岩组第三段含煤沉积是在受限制的聚煤凹陷中形成的,成煤作用是复杂和不均一的,含煤岩系形成时的坳陷内部存在构造分异。早二叠世童子岩组早期龙永煤田内为浅海相的沉积环境;中期开始的区域性大海退逐渐形成的滨海、海湾泻湖及近海湖泊、泥炭沼泽等环境,并形成了童子岩组第三段含煤建造;晚期海水由东北向西南退出,古地理环境是由浅海向陆地迁移,从而结束了童子岩组地层的含煤建造,预示东吴运动来临。

Long john coalfield paleogeographic analysis indicates that：tongziyan third paragraph of the coalbearing deposits is restricted coal accumulation in the depression formed into the role of coal is a complex heterogeneous, coal-bearing rocks during the formation of au exist within the settlement structure differentiation. Early permian tongziyan early longyong coal deposition within the shallow marine environment; mid back gradually formed a regional coastal ocean, bays and coastal lakes, lagoons, peat swamps and other environmental, and formed a rock group of the third boy the construction of coalbearing section; late sea water from northeast to southwest exit, the ancient geographical migration from shallow water to land, thus ending Tongziyan construction of coalbearing strata, indicating the advent of soochow movement.