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
Mesangiospermae are fossil mesangiosperms from the Hauterivian stage of the Cretaceous period. Molecular clock comparisons of DNA sequences indicate that the mesangiosperms originated between 140 and 150 Mya (million years ago) near the beginning of the Cretaceous period. This was about 25 Ma (million years) after the origin of the angiosperms in the mid-Jurassic. By 135Mya, the mesangiosperms had radiated into 5 groups: Chloranthales, Magnoliids, Monocots, Ceratophyllales, and Eudicots. The radiation into 5 groups probably occurred in about 4 million years. Because the interval of this radiation (about 4 million years) is short in proportion to its age (about 145 million