Geology of Colombia refers to the geological composition of the Republic of Colombia that determines its geography. The territory of Colombia covers vast areas within the South American plate, where most of the emerged land is, the Caribbean plate and the Nazca plate.columbia containing five main natural regions that present their own unique characteristics, from the Andes mountain range region shared with Ecuador and Venezuela; the Pacific Ocean coastal region shared with Panama and Ecuador; the Caribbean Sea coastal region shared with Venezuela and Panama; the Llanos (plains) shared with Venezuela; to the Amazon Rainforest region shared with Venezuela, Brazil, Peru and Ecuador. Colombia is one of only two South American countries which border both the Atlantic and Pacific Oceans.Colombia is formed by two great territorial zones, one submerged in the Pacific Ocean and the Caribbean sea covering a total area of 828,660 km² and the second is the emerged land which is formed by the Andes mountain range and the Llanos plains that are shared with Venezuela and cover an area of some 1′143,748 km².the emerged zone include the Meta, Vichada and the Inirida rivers which contribute to other major rivers like the Orinoco River, Vaupés River, Caquetá River, Putumayo River and Apaporis River.The Andean Region of Colombia is the other emerged area of the two areas that compose the geology of Colombia.The Cordillera Central formed from the Guyana shield during the Paleozoic era with intrusions from granite and metamorphism.