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
Geology of Arizona The subduction of the Farallon Plate beneath western North America remains a poorly understood event, although new seismic and computer tomography modeling is shedding light on the event. As the oceanic plate subsided under North America, it generated partial melting conditions that formed volcanoes on the surface in California and Arizona. Volcanic activity commenced in western Arizona around 205 million years ago, kicking off the Nevadan orogeny, which lasted until 145 million years ago, spanning the Triassic into the Jurassic. Granite intrusions 190 million years ago enriched many veins with minerals and generated copper porphyry gold deposits. Bisbee, Arizona, 92