Chongqing is known as a city built on the back of dinosaurs, on June 28, 2017, the Information Office of the Chongqing Municipal Government held a press release announcing that the dinosaur fossil group found in Pu'an Township, Yunyang County, Chongqing is a world-class dinosaur fossil group identified by the National Paleontological Fossil Expert Committee. The excavation of paleontological fossils in Pu'an Township, Yunyang County, was immediately carried out. Through rescue excavations, a "dinosaur fossil wall" of 150 meters long, 2 meters to 4 meters wide and 6 meters to 8 meters high has been formed, with a wall area of 1155 square meters and 17 fossil-enriched communities.
According to the detection, there are still a large number of dinosaur fossils under the wall, buried at a depth of at least 20 meters. Chongqing dinosaur fossil resources are rich, from the first discovery of bird foot dinosaur fossils in beibei district in 1939 to the world-class dinosaur fossil group found in Pu'an Township, Yunyang County in 2015, at present, 24 of the 38 districts and counties in Chongqing have successively found dinosaur fossils, 63 dinosaur fossil excavation sites, only 28 in the main urban area. Chongqing is an important producer of Jurassic dinosaur fossils in the Sichuan Basin, and one of the important production areas of Jurassic dinosaur fossils in the country and even in the world. Dinosaur fossils in Chongqing are not only widely distributed, but also very rich in species. Nine relatively complete dinosaur fossils have been excavated in the city, including Hechuan Mamenxi Dragon, Dashi Mamenxi Dragon, Longevity Emei Dragon, Shenzhou Bayu Dragon, Upstream Yongchuan Dragon, South Bank Yongchuan Dragon, Giant Yongchuan Dragon, Jiangbei Chongqing Dragon and Fruit Shell Qijiang Dragon.
In addition, there are a large number of solid fossil materials, such as the Pu'an dinosaur fossil group. The most representative fossils of the relics are the Qijiang dinosaur footprint fossil group, the Dazu Postal Pavilion dinosaur turning footprint fossil and so on. Among these dinosaur fossils, there are many world-renowned star dinosaurs, such as the most complete preserved sauropod dinosaur fossil found in China so far, "Hechuan Mamenxi Dragon". At present, it is the only well-preserved dinosaur footprint in the world, with all types of dinosaur footprints, and also has the country's first ankylosaur footprint fossil "Lotus Fort Zhai Dinosaur Footprint Fossil Group". 329 dinosaur footprints were found in the cavity of the Lotus Baozhai cliff in Hongyanping, which is the largest dinosaur footprint group found so far in the Cretaceous strata in southwest China.
At present, there are 5 kinds of dinosaur footprints, including dinosaur positive footprints, dinosaur negative footprints, dinosaur dynamic footprints, dinosaur stereoscopic model footprints and dinosaur footprints, including the Chinese Qijiang footprints of the ankylosaurus suborder, the agile dance footprints of theropod suborder, the hot old Yingshan footprints of the bird's foot suborder and the lotus Kalier footprints, among which the Chinese Qijiang footprints are the first footprints of ankylosaurs have been found in China. In addition, fossils such as dinosaur skin and hair marks, and dinosaur feces have been found in the park. For example, the world's rare dinosaur turning track "Postal Pavilion Dinosaur Turning Footprint Fossil", there is a rock layer with an inclination of about 60 degrees on the side of an abandoned railway in Youting Town, Dazu District, Chongqing, which preserves a large number of dinosaur footprints.
These dinosaur footprints are sauropod footprints of the early Jurassic period, and the inner width of their tracks is longer, which is more special among existing discoveries. More rarely, a dinosaur track there shows obvious signs of turning. This discovery has been a great help in the study of dinosaur behavior and kinematics, and can also help restore the paleoenvironment of the time.