Geology of Colombia ocean invaded the area which is exposed in Colombia's Andean zone, as subterranean volcanic eruptions in the western part of the country spouted lava. In the Triassic Period of the 186-million-year-long Mesozoic Era, which began 252 million years ago, the sea that occupied the Andean zone separated into two parts after the Cordillera Central rose. Large layers of sedimentary rock were deposited during the Jurassic Period, which ended with great igneous activity. During the Cretaceous Period, the sea to the east of the Cordillera Central extended to Putumayo region in the south, while subterranean volcanic activity continued to the west
Wasson Bluff dinosaur tracks, at his Parrsboro Rock and Mineral Shop and Museum. One of them, also found at Wasson Bluff, is a track that may have been made by a primitive, two-legged, crocodile-like creature that was nearly long. In January 1986, American paleontologists Paul Olsen and Neil Shubin announced they had recovered hundreds of thousands of bones at Wasson Bluff, the largest fossil find in North America dating from the geological period 200 million years ago known as the Triassic-Jurassic boundary. It was a time when massive lakes of lava spewed from fissures in the earth as the supercontinent Pangea broke