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
Cretaceous Dawn Cretaceous Dawn Cretaceous Dawn is a science-fiction novel by sibling scientists Lisa M. Graziano and Michael S. A. Graziano, published in 2008 by Leapfrog Press (initially published as 'Hell Creek: 65 Million Years in the Past, the Journey Begins' under Trafford Publishing in 2006. The book contains 304 pages. Its story is set to a modern time and also to the prehistory of 65 million years ago (at the end of the Cretaceous era). It starts in the physics laboratory, where long-extinct beetles start to appear. Four people and a dog are then hurled 65 million years through the deep