湖北宜昌下奥陶统分乡组藻－海绵礁

ALGAL-SPONGE REEFS IN LOWER ORDOVICIAN FENGXIANG FORMATION, YICHANG, HUBEI

朱忠德 姜衍文 刘秉理 胡明毅 肖传桃

Zhu Zhongde Jiang Yanwen Liu Bingli Hu Mingyi Xiao Chuantao

新发现的藻-海绵礁产于下奥陶统分乡组上部,时代相当于Tremadocian晚期。与礁有关的主要为碳酸盐颗粒岩、泥岩等岩相。沉积层序表明藻-海绵礁是一个由浅变深的演化序列,以沙浪底形为礁基,并在生长过程中强化了此一形态。粘结、障积作用为主,构成-藻群落;藻-群落。

Algal-sponge reefs have been discovered recently in the upper part of the Lower Ordovician Fengxiang Formation, and their age corresponds to Late Tremedocian. The reefs consist mainly grainstone, mudstone,boundstone and bafflestone. The depositional sequence of the algal-sponge reefs suggests a evolution series starting from shallow to deep. The reefs grew on relief bases, and then enhanced the initial forms of the bases as they grew. Bounding and baffling were the main factors in the formation of Calathium-algal and algal-PulchrilaminaArchaeoscyphia communities.

10.11743/ogg19950404