摘要
通过综合多方面的地质资料，包括岩性、沉积构造、生物的生态类型、碳酸盐台地的迁移以及坡折位置的变更等来判断湘西北地区奥陶纪海平面变化．在湘西北地区海水深浅变化、台地边缘迁移和坡折位置的变更表现出相似的规律，从而可勾画出海平面变化曲线．两河口阶和宝塔阶是海平面上升期，庙坡阶和五峰阶是海平面下降期，其间牯牛期有一次小规模的海平面变化．该区三次海平面升降旋回与Ｒｏｓ于１９８８年所作的全球海平面变化旋回基本一致．
Researches and correlation of three outcrop sections in the southern margin of Ordos basin indicate that 14 third-order sequences can be recognized from Xinji Formation in Lower Cambrian to Fengshan Formation in Upper Cambrian, each of which generally includes 1～3 standard trilobita zones and has 2～3Ma duration except two Lower Cambrian sequences dated probably more than 5Ma. Subsidence analysis provides a representative exponential curve ( R 1 curve) which can be compared with Mckenzie's cooling plate model for passive margin, and good second-and third-scale of accommodation change curves ( R 2 curve and R 3 curve). R 2 curve is especially very similar to that of the Great Basin.
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
1997年第5期479-483,共5页
Earth Science-Journal of China University of Geosciences
基金
国家基础性研究重大项目"中国古大陆及其边缘层序地层及海平面变化研究(SSLC)"资助
关键词
碳酸盐台缘
海平面升降
奥陶纪
湘西北
地层
third-order sequence, sea level change, Cambrian, southern margin of Ordos basin.
