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Volcanic and Seismic Events as Proof of Plate Tectonic Theory

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Volcanic and Seismic events are major pieces of evidence towards proving that plate tectonics theory is valid.
A seismic event is the transient motion and release of kinetic energy caused by sudden failure of the earth's crust, usually felt as shaking or tremors in the rock mass. Seismic events range in size from barely perceptible tremors to major earthquakes. Volcanic events occur when there is a release of magma, gas and ash from the Earth’s crust.
The entire outer surface of the planet is divided into these plate formations with approximately 30 in total. These different plates vary in size from over 100,000,000 square miles, for example The Pacific Plate, to the Galapagos micro plate at 12,000 square miles. Fault lines separate each …show more content…

New Basaltic magma rises to the surface, cools and pushes the plates apart. The convection currents also help drag the plates apart and then pull them down at convergent boundaries. This can be seen at the mid-ocean ridges. Eruptions are non-violent with the exceptions of the East African Rift Valley where the recent eruption in 2002 in the Republic of Congo had a devastating effect on the local population, and where the ocean ridges rise up out of the sea such as in Iceland.
The theory of plate tectonics also explains the formation of destructive plate boundaries which account for creating 80% of the world’s active volcanoes. The melting crust at Subduction Zones (oceanic-oceanic or continental-oceanic) are due to differences in density between oceanic and continental lithospheres, where the less dense plate is pushed beneath the more dense plate, and becomes part of the asthenosphere forming magma that is andesitic in its nature. This creates the most violent volcanic activity. Island Arc volcanoes such as Pinatubo and Fold Mountain Volcanoes such as Nevado Del Ruiz (Andes) are very destructive.
The evidence for deep, hot, convective currents combined with plate movement (and concurrent continental drift) also explained the mid-plate "hot spot" formation of volcanic island chains for example the Hawaiian Islands and the formation of rift valleys such as The Rift Valley of Africa. Mid-plate earthquakes, such as the powerful New Madrid

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