首次在山东郯城早白垩世晚期地层中发现恐龙足迹化石,分属蜥脚类和兽脚类恐龙足迹,足迹大小差异较大。通过对山东省郯城县新发现的2处恐龙足迹化石点和江苏省东海县南古寨恐龙足迹化石点的对比研究,探讨了足迹类型、大小、速度与足迹深度的关系,发现同等条件下,蜥脚类恐龙足迹通常较兽脚类足迹深,而蜥脚类恐龙足迹深度随着足迹大小的增加有变深的趋势;波痕、雨痕和泥裂等沉积构造以及足迹回填和叠覆现象对足迹化石保存形态和细节有较大影响,而构造变形对足迹形态和行迹并无明显影响,但高角度的构造变形会加速差异风化,使足迹化石更易暴露而被破坏。对研究区古环境与古生态的研究表明,早白垩世晚期研究区经历了水体逐渐变浅、气候由湿到干并伴随短暂间歇性干旱的过程,沉积环境由河湖演变为三角洲前缘、并逐渐过渡到三角洲平原,生态环境逐渐恶化,动植物由兴而衰、逐渐减少。
Lots of dinosaur footprints belonging to sauropod and theropod were first discovered in the upper Lower Cretaceous in Tancheng County, Shandong Province. The footprints vary in size. By compa ring the study between the two new dinosaur track sites in Tancheng of Shandong Province and Nanguzhai of Jiangsu Province, we discussed the relationship among the footprint types, size, depth and walking speed, and found that under the same conditions, sauropod footprints are always deeper than those of the ropod, while with the increase of the footprint size of sauropod, the depth shows a shallowing trend; sedi mentary structures like ripples, rain marks and mud cracks, and footprint backfilling and overlaying have relatively greater impacts on saved forms and details, while structural deformation has no obvious effect on footprint forms and tracks, but high angle deformation would increase the differential weathering, making the fossils easier to be exposed and be destroyed. The study on palaeoenvironment and palaeoecology shows that the study area experienced a process of water gradually shallowing and climate changing from humid to dry with short intermittent drought, sedimentary facies evolved from fluviolacustrine to delta front, and gradually to delta plain, and the palaeoecological environment gradually deteriorated, the fauna and flora declined and the amount gradually decreased.