Reconstruction of a mid-Jurassic sauropod dinosaur. (Photo courtesy of the research group)
Hubei dinosaur footprints. (Photo courtesy of the research group)
On January 6, a team of Chinese and foreign scientists released a research report that found fossilized Jurassic dinosaur footprints for the first time in the Zigui Basin in western Hubei. The dinosaur footprints found this time include at least 11 footprints, of which 9 sauropod footprints can form a single footprint, and 1 isolated sauropod footprint and 1 isolated theropod footprint.
This discovery enriches the types of dinosaur fossils in Hubei and is of great significance for understanding the range of dinosaurs in the middle Jurassic period of China, the paleogeographical distribution and the composition of dinosaur fauna in Hubei, China. The research paper was published in the paleontological journal Historical Biology.
In July 2022, scholars such as Wang Yongdong, researcher Zhang Haichun and assistant researcher Li Liqin of the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences discovered and preliminarily confirmed it when they explored the field teaching practice route of paleontology in the South China formation. Subsequently, scholars from Nanjing Institute of Geology and Paleontology and Xing Lida research group from China University of Geosciences (Beijing) conducted joint investigation and research in the fossil source area. Since the footprints were kept high on the rock wall, the expedition team members used means such as rock climbing and drone equipment to investigate and measure, and obtained a large amount of data.
Footprint fossils are preserved in silty mudstones of the Middle Jurassic (Middle Jurassic) Vent Formation. The native sedimentary structures such as mud cracks and wave marks preserved in the same layer, as well as insect traces and bivalve fossils, indicate that the area was once a lake sedimentary environment, and the plants and pollen fossils produced in the same layer indicate that the vegetation type prefers arid and hot, indicating that the area was hot and arid.
This time, 10 sauropod footprints were found, including 5 front feet and 5 back feet, of which 9 formed a track. All footprints are heavily weathered and poorly preserved. According to the aspect ratio of the footprint, the width of the track and other characteristics, the track can be classified as Brontopodus-type.
The research team estimated that the creator was a sauropod about 4 meters long, with a walking speed between 3.89 km/h and 6.08 km/h. This size may represent juvenile individuals of large sauropods or small sauropods. An isolated and incomplete footprint is classified as a three-toed carnivorous theropod footprint, which is also poorly preserved to determine the specific footprint classification, and the overall morphology is very close to the Eubrontes type.
There are not many dinosaur fossil records in Hubei Province, mainly concentrated in the Cretaceous strata of Yunyang, which are a large number of dinosaur egg fossils and a small number of dinosaur bone fossils. Previously, no fossils related to Jurassic dinosaurs had been found in Hubei Province, and this discovery is important evidence that Jurassic dinosaurs were active in the Zigui Basin of Hubei Province.
The fossil origin of Xiakou footprint belongs to the Zigui Basin in terms of geological structure, which is only 200 km away from the Yunyang fossil site in Chongqing, which was contemporary. The Zigui Basin is also part of the eastward extension of the Sichuan Foreland Basin, so the footprinters found this time are likely to have some connection with dinosaurs in the Yunyang area, and the dinosaur fauna of the Jurassic in the Zigui Basin is likely to be similar to the Yunyang area. Moreover, small pterosaurus footprints are rare, and the research team has only found similar tracks in Sichuan, Tibet and Yunnan. Scholars have also studied and discussed the combination of footprints in these three regions, and believe that the fauna of these three regions is linked. It is likely that the dinosaur fauna of the Zigui Basin is also associated with the fauna of these three regions. (Source: Cui Xueqin, China Science News)
Related paper information:https://doi.org/10.1080/08912963.2022.2164494