摘要
从全球范围来看,白垩纪四足动物的足印多数是非鸟恐龙与鸟类留下的痕迹;少量足印来自翼龙、鳄鱼、龟、哺乳动物和其他四足动物。白垩纪的足迹化石以东亚(尤其是中国和朝鲜)和北美西部的最为人所知。南美(主要是阿根廷和巴西)也有一定数量广泛分布的足迹化石,欧洲、非洲与澳大利亚的白垩纪足迹组合则鲜为人知。以白垩纪四足动物的足印记录为基础,我们对两个全球足印生物年代重新进行了检查。早白垩世生物年代以蜥脚类与鸟脚类的足迹为特征。晚白垩世生物年代中的蜥脚类足迹较少,但是鸭嘴龙、暴龙和角龙的足迹增多了。另外,白垩纪足印化石的记录中记载了许多重要的生物地层学信息,如北美白垩纪中期蜥脚类恐龙的消失,以及白垩纪末恐龙的绝灭。越来越多来自东亚的白垩纪足印记录使我们对更精细的地方性白垩纪足印生物年代学有了初步印象。因此,以地方性四足恐龙(包括鸟类)遗迹属的地层分布为基础,可以识别出三个或四个足印生物年代。种类丰富并具有地方性特色的东亚的白垩纪鸟类动物的遗迹群,可能指示白垩纪时东亚存在着一个独特而繁盛的鸟类动物群。以足印化石为基础的这一假说有待进一步的验证。
The global record of Cretaceous tetrapod footprints is dominated by the tracks of non-avian dinosaurs and birds; fewer tracks are known of pterosaurs, crocodylians, turtles, mammals, and other tetrapods. The Cretaceous track record is best known from East Asia （especially China and Korea） and western North America. A moderately extensive record is also known from South America （primarily Argentina and Brazil）, but Cretaceous track assemblages from Europe, Africa, and Australia are much more poorly known. Here, we re-examine two global footprint biochrons based on the Cretaceous tetrapod footprint record. An Early Cretaceous biochron is characterized by sauropod and ornithopod tracks. A Late Cretaceous biochron has fewer sauropod tracks but adds the tracks of hadrosaurs, tyrannosaurids, and ceratopsians. Furthermore, the Cretaceous footprint record documents many important biostratigraphic data points, such as the mid-Cretaceous extirpation of sauropod dinosaurs in North America and the terminal Cretaceous extinction of dinosaurs. A growing Cretaceous footprint record from eastern Asia also provides the first glimpse of a more refined, provincial Cretaceous footprint biochronology, in which three or four Cretaceous footprint biochrons based on the stratigraphic distributions of endemic theropod dinosaur （including bird） ichnogenera may be recognizable. The abun- dance and endemism of this east Asian Cretaceous avian iehnofauna may indicate that a unique and prolific avian fauna existed in eastern Asia during the Cretaceous, a footprint-based hypothesis that merits further testing.
出处
《地层学杂志》
CSCD
北大核心
2012年第2期503-550,共48页
Journal of Stratigraphy
基金
国家自然科学基金(No.91114201)
国家重点基础研究发展计划(2012CB821906)资助出版
关键词
生物地层学
足印
四足动物
白垩纪
亚洲
北美洲
南美洲
biochronology, footprints, tetrapoda, Cretaceous, Asia, North America, South America
