Quilotoa Is a water-filled caldera and the most western volcano in the Ecuadorian Andes. The 3-kilometre (2 mi)-wide caldera was formed by the collapse of this decide volcano following a catastrophic VEI6 eruption about 800 years ago, which produced pyroclastic flows and lahars that reached the Pacific Ocean, and spread an airborne deposit of volcanic ash throughout the northern Andes. This last eruption followed a dormancy period of 14,000 years and is known as the 1280 Plinian eruption. The fourth (of seven) eruptive phase was phreatomagmatic, indicating that a Crater lake was already present at that time. The caldera has since accumulated a 250 m (820 ft) deep crater lake, which has a greenish color as a result of dissolved minerals. Fumaroles are found on the lake floor and hot springs occur on the eastern flank of the volcano
The Galápagos Islands (official name: Archipiélago de Colón, other Spanish name: Islas Galápagos, Spanish pronunciation: are an archipelago of volcanic islands distributed on either side of the Equator in the Pacific Ocean surrounding the centre of the Western Hemisphere, 906 km (563 mi) west of continental Ecuador, of which they are a part. The Galápagos Islands and their surrounding waters form the Galápagos Province of Ecuador, the Galápagos National Park, and the Galápagos Marine Reserve. The principal language on the islands is Spanish. The islands have a population of slightly over 25,000. The islands are known for their vast number of endemic species and were studied by Charles Darwin during the voyage of the Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by natural selection.