陕西安塞首次发现中侏罗世晚期恐龙足迹

First discovery of dinosaur footprints in the late Middle Jurassic in Ansai district,Shaanxi Province

在安塞地区野外地质考察过程中,在直罗组顶部的一套砂岩地层中发现4枚恐龙足迹,其中3枚为三趾型恐龙足迹;另外还观察到3枚疑似恐龙足迹。根据足迹形态对比和足迹特征研究,推断P3观察点三趾型恐龙足迹造迹者为大型肉食性兽脚类恐龙,其他足迹的造迹者难以确认。该发现不仅扩大了鄂尔多斯盆地中侏罗世恐龙足迹的分布范围,也为研究直罗组晚期的古环境提供了素材。

During the field geological survey in Ansai area,four dinosaur footprints were found in a set of sandstone strata on the top of Zhiluo Formation,three of them were three-toed dinosaur footprints.In addition,three suspected dinosaur footprints were observed.Based on the comparison of footprints characteristics,it is inferred that the three-toed dinosaur footprints of the P3 observation point are largely caused by carnivorous dinosaur,the other footprints are difficult to identify.This discovery not only expanded the distribution of dinosaur footprints in the Ordos Basin during the Middle Jurassic,but also provided materials for further studying the paleoenvironment of the late deposition of Zhiluo Formation.