Volcanism is an ever present feature of our planet's (and many others') geological activity. Volcanoes provide evidence for the movement of tectonic plates, and allow us to study the mineral composition of magma far below the Earth's surface. For this weeks virtual tour, we will be taking a marine submersible 4600 feet below the Earth's surface to study the Axial Seamount.
We are studying the Axial Seamount for several reasons. For one, most volcanoes on earth are actually underwater, a fact which is obvious given that oceans cover the majority of the Earth's surface, but which is often lost on people when considering volcanic activity. Underwater volcanoes have created most of the chemical composition of the Ocean floor, and we can witness this in the 40 ft thick lava flows around the Axial Seamount.
Volcanoes usually lie along regions where tectonic plates are colliding, called subduction zones. The Axial Seamount, however, has a somewhat mysterious position that isn't entirely understood by scientists. It is believed to have formed over the Cobb hot spot, which is long dormant. Much expansion has occurred in the region, leading to the Axial Seamount and a chain of volcanoes it resides alongside to move over the last several hundred thousand years. It is believed that the Seamount is older than the oceanic ridge it currently bisects, which is not a common phenomenon.
Due to its interesting geological history, the Axial Seamount is one of the most widely studied sub oceanic geological features today.
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