on March 17, 1964, Good Friday, most Alaskans were heading home from work and starting their dinners when the ground started to shake. Almost the mother of all earthquakesĪt 5:36 p.m. It was in one such subduction zone, where the Pacific Plate was being overridden by the North American Plate, that Earth's second most powerful earthquake ever recorded took place. The Hunga Tonga-Hunga Ha'apai volcano was created by the Pacific Plate subducting beneath both the Indo-Australian Plate and the Tonga Plate.īesides creating volcanoes, subduction zones are where Earth's most violent earthquakes take place. The magma then rises to the surface and can cause volcano formation. Subduction zones are areas where one tectonic plate slides beneath another, causing rocks to melt and creating magma. This movement can lead to the formation of mountains, lakes, and seas, as well as earthquakes. The plates move relative to one another, and at their boundaries, they can converge (called a destructive boundary), diverge (called a constructive boundary), or slip beneath each other (a transform boundary). The lithosphere is comprised of eight major plates and a number of smaller plates, including the North American, Caribbean, South American, Scotia, Antarctic, Eurasian, Arabian, African, Indian, Philippine, Australian, Pacific, Juan de Fuca, Cocos, and Nazca plates.
The heat from the mantle causes the rocks at the bottom of the lithosphere to become slightly elastic, which allows the plates to move.
The Ring of Fire is where several of Earth's tectonic plates meet and create subduction zones. The theory of plate tectonics was formulated during the 1960s, and it describes the 60-mile-thick (100 km) outer layer of the Earth, known as the lithosphere. The Ring of Fire is over 25,000 miles (40,000 km) in length, running in a circular arc northward from New Zealand to Australia, then onward from Indonesia to the Philippines and Japan, then stretching eastward to the Aleutian Islands, and southward down the west coast of North America and along the west coast of South America.
The Ring of Fire The Pacific Ring of Fire.