【摘要】 在海南岛中部儋州-屯昌地区前人划归石炭系地层中采获放射虫等古生物化石,新厘定出一套二叠系地层。其下部为一套滨浅相碎屑岩,局部夹碳酸盐岩、变质基性火山岩;上部为一套深水沉积岩系夹硅质岩,局部夹变质基性火山岩。与海南岛西部、西南部一带出露的二叠世地层比较,岩性组合特征、沉积类型、沉积相、生物富集程度和属种组分及所处沉积构造背景均存在显著差异。该套地层的确定,对研究海南岛二叠纪地层的沉积相,重塑古地理环境,以及研究古特提东延及构造演化等问题具重要意义。更多还原

【Abstract】 Fossiles,shuch as Radiolaria etc.,were collected from the strata assigned previously to the Carboniferous in the area of Danzhou-Tunchang in central Hainan.Now the age of the strata has been determined to be Early-Mid Permian which divided into two parts.The lower part formed in a littoral-epeiric environment,is a series of clastic rocks,partly contains carbonate rock and metamorphic basic volcanic rocks and the upper part formed in a bathypelagic environment is a series of sediments with chert,partly contains metamorphic basic volcanic rocks.In comparision with the Early-Mid Permian strata exposed widely in the western and western-southern Hainan island,there are appreciable difference in the features of the lithologic association,sediment type,fossil concentration and generic and species components,as well as the geological setting.The determination of this sequence of strata has great significance for the study of the sedimentary facies of the Early-Mid Permian strata and reconstruction of the paleogeographic environment in Hainan and the study of the stratigraphic evolution in the Palaeotethyan tectonic development stage and tectonic setting of the basin in Hainan and its adjacent areas.更多还原