Welcome to the Galapagos Islands! The Galapagos are an archipelago of several volcanic islands located in the Pacific Ocean. The archipelago consists of 13 major islands, six minor islands, and 40 smaller rock formations and reefs spread out over 17,000 square miles of ocean. They are born to create fire, and in the last 200 years a remarkable 50 plus eruptions have occurred. Looking into the geographic location and plate tectonic settings can easily help show why more than 50 eruptions have occurred in such a short period of geologic time.
The Galapagos Islands are located on the equator west of the South American coast. Like many oceanic islands, they are formed by a mantle plume or hotspot like Hawaii. A major subduction zone currently sits under the islands, the two plates that are subducting beneath the South American and Caribbean plates are the Nazca and the Cocos plates. The Galapagos were created by the Cocos and the Nazca plate, which are currently moving east-southeast, and will continue to create an extended chain. With time the plume will burn through the crust to form an underwater volcano which will eventually grow large enough to become an island like the many others. Since the crustal plate is in constant motion the plates move over the mantle plume, and many years later a chain of volcanoes are created like the Galapagos. Volcanoes get older in the direction of plate movement, so the Galapagos volcanoes get older to the south-southeast, and the oldest volcano is named, Espanola. The Galapagos mantle plume is over 90 million years old, and has created many islands and volcanoes, with more to come. Yet, the actual islands are no more than a little over four million years old.
Uniquely it is quite unusual for a mantle plume to produce so many simultaneous active volcanoes, which make the Galapagos truly a place to create fire. Also another interesting fact is that Charles Darwin was first to recognize that the cones of the volcanoes form...
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