The Galápagos Islands Hot Spot and its source of volcanic activity
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The islands follow a chain pattern where the older islands are found in the East, while the younger islands are found in the West. This very simple geological feature is responsible for the unique development of flora and fauna, rates of erosion, frequency of volcanic eruptions, and of course, the always unpredictable rates of colonization. Geologists explain this with lots of interesting facts. The theory states that there is a Mantle Plume that is relatively stationary. This mantle plume is of intense heat and deforms the land above it. The crustal plate rides over the hot spot and is occasionally perforated by the molten rock that is rising from the Earth's mantle. The crust above, is forced upward because of the heat, and volcanoes are formed. The previously formed islands then move slowly away from the hot spot, making room for new islands to be formed by further volcanic activity. The older volcanoes eventually become inactive and slowly erode into the ocean depths. Hot Spots are responsible for the formation of Hawaii, the Galápagos, and other island chains. The Galápagos Hot Spot is currently located beneath the northwestern region of the Galápagos Archipelago near Fernandina and Isabela. The width of the hot spot is estimated to be approximately 150 kilometers (100 miles). Since the Galápagos Islands are moving with the Nazca plate and the hot spot remains stationary, the islands form and slowly drift away from the hot spot, at about 5cm per year, allowing more volcanoes and islands to be formed. Since the Galápagos Islands move with the Nazca plate in an east-southeast direction the older islands are found in the southeast. The newly forming islands are located in the northwest. Since all of the volcanoes are formed underwater, the material forming them builds and accumulates as it spreads out like a sand hill. This process creates the islands in the form of a volcano with gentle sloping sides and a central vent. This type of volcano is known as a shield volcano. The greatness of the Galapagos wildlife, is certainly enhanced by the beauty of its many geological features. The Hot Spot theory is one way of explaining, not only why change rules in oceanic islands, but also how wildlife has adapted to the different islands that make up this ever-changing land. If you plan to visit the Galapagos Islands take a look to this sources:
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