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
Wallowa Mountains addition there are many older terranes between the batholith and basalt flows. The Wallowa Batholith is formed of granite from a magma upwelling in Late Jurassic and Early Cretaceous time (between 160 million and 120 million years ago). The placement of this rock caused uplift of the surface, which at the time was tropical sea. This is evident from the slate, quartzite, and marble present in the mountains, which come from metamorphism of the sedimentary deposits of oceans during the Triassic. At the center of the Batholith are granodioritic rocks, while the outer limits of the range are tonalitic. The