湖北东岳地区中寒武统藻类化石的发现及其环境、构造古地理的意义

湖北东岳地区位于豫、鄂两省交界处,西靠陕西(图1)。构造位置处于东秦岭中部地区。区内下、中寒武统剖面连续,出露良好,尤其是中寒武统地层分布广泛,为一套不纯的碳酸盐岩沉积。过去由于在该套地层中始终未获得大古化石,也没有根据盆地碳酸盐岩特有的鉴定标志,如微体化石、特有的动物群和沉积构造,而是仅仅根据其缺乏化石,颜色较深、岩性粒度较细,把它作为陆棚边缘相或盆

THE DISCOVERY AND ENVIRONMENTAL AND TECTONOPALAEOGEOGRAPHIC IMPLICATIONS OF THE MIDDLE CAMBRIAN ALGAL FOSSILS IN THE DONGYUE DISTRICT,HUBEI

For the first time this paper describes cryptalgalaminates which occur in substantial amounts in non-fossiliferous Middle Cambrian carbonate rocks from the Dongyue district, Hubei. These cryptalgalaminates of different ages and diverse morphologies are closely related with sedimentary environments, thus may be interpreted as a good facies indicator. The discovery of the cryptalgalaminates helps dispel the misunderstanding that the Middle Cambrian strata in the study area are ascribed to the deeper-water sediments, and contributes to the study of the tectono-palaeogeographic changes in the Qinling area during Middle Cambrian time.