【摘要】 本文通过岩性特征、粒度分析、沉积构造、遗迹化石、生物组合等方面的研究分析认为,乌当湄潭晚期为一浅海内陆棚沉积环境,陆棚内有微地貌起伏。区内第三层石灰岩具有明显的风暴岩特征,第一层层状燧石(或海绵)岩为原始沉积,并与硅质海绵生物关系密切。更多还原

【Abstract】 By studying and analysing the characteristics of the rocks,of the grainsize and structure of the rock deposits,and of trace fossils and biocommanity,We come to the conclusion that in WuDan district the late Meitan age had formed the enviroment of shallow shelf in which the trough valley had developed.There are obvious charicteristics of storm rock in the limestone of the third member in Meitan formation, and flint formation is thought to be the primary deposit in the first member of Meitan formation.There is a close relationship between flirt- ts and siliceous spongia.更多还原