株洲天元白垩纪含化石层地质记录及恐龙死亡、埋藏过程初探

株洲天元恐龙化石遗迹区，是湖南省新发现的一个恐龙化石产地，亦是当今世界上为数不多的位于大中城市中心的恐龙化石埋藏地之一。本文在区域资料的基础上，首次在上白垩统含化石层段中识别出暴露地质记录、洪水记录及震积记录等3个特殊的地质体；同时，通过大量砾石的科学统计，明确了株洲天元湖盆的古流向为自南往北，进而指出恐龙生活在呈NE-SW向展布的株洲湖盆南岸。在上述研究基础上，本文推测：在气候干旱少雨、植被稀少的古环境中，火山（?）、地震、滑坡、洪积等一系列局部性突发的地质事件直接导致了株洲天元地区生态环境的恶化，这亦成为该区恐龙死亡的主导因素。其骨骼埋藏与河道冲积入湖形成三角洲沉积体系这一过程密切相关。

Geological records of fossils layer and death process and taphonomy of dinosaurs in Cretaceous in Tianyuan, Zhuzhou

Based on the study of regional geological data, the authors recognized 3 sedimentary events in the Upper Cretaceous formation for the first time, with the 3 geological records being exposure geological record, flood geological record and earthquake geological record. In addition, on the basis of lots of scientific statistics of gravels, the authors discussed the paleocurrent direction as well as provenance of the lake basins in Tianyuan of Zhuzhou systematically. The authors found that dinosaurs lived on the west bank of a long narrow NE-SW distributed lake in the south part of the Zhuzhou lake basin. Based on the results obtained, the authors infer that local volcano (?), earthquake, landslide and pluvial events are the reasons for paleocimate change and animals'' death as well as the main reasons for the death of dinosaurs in the palaeoenvironment with dry weather and scarce forest vegetation. The burial process was closely related to the delta deposit system from channel alluvial.