中国奥陶纪岩石地层划分和对比

LITHOSTRATIGRAPHIC SUBDIVISION AND CORRELATION OF THE ORDOVICIAN IN CHINA

本文根据当前国际通用的奥陶系"三统七阶"划分标准,对中国华南、华北、塔里木、准噶尔、柴达木、西藏、滇缅马、印支等块体的奥陶纪岩石地层单元进行了系统性梳理和总结,在大量近期研究成果的基础上,厘定它们的岩性特征、地层时代、接触关系和划分对比,以统一的年代地层框架为标尺,建立了94个地层柱的岩石地层划分和对比关系。根据近二十年来中国关于奥陶纪的大地构造、沉积学、地层古生物学和生物古地理学研究成果,将中国奥陶系划分为12个地层区,其中对华南、华北和塔里木地层区进一步划分为若干个地层分区和地层小区。

Under the framework of the international Ordovician standard chronostratigraphy,some 94 lithostratigraphic sequences from the principal terranes or blocks of China,such as South China,North China,Tarim,Junggar,Qaidam,Tibet,Sibumasu,Indochina etc.,are systematically summarized,clarified and revised.As results,a refined,comprehensive correlation chart is made to illustrate the main lithology,age,contact and correlation of all the relevant lithostratigraphic units.Based on the latest advances in tectonics,sedimentology,palaeontology,stratigraphy and palaeobiogeography of the Ordovician study in China,twelve stratigraphic regions are recognized,amongst which South China,North China and Tarim are further subdivided into several subregions respectively.