Video:The Pacific Ring of Firewith Bulk Item
The Ring of Fire, which surrounds the Pacific Ocean, possesses the most volcanoes and earthquakes more than anywhere else in the world. Learn about this hot destination, and why it has so many volcanoes.See Transcript
Transcript:The Pacific Ring of Fire
Ring of Fire Overview
The ring of fire is home to the most of the world's seismic activity. Named after the incredibly high amount of volcanic activity, the horseshoe shaped area around the Pacific Rim is home to 75% of the world's active and dormant volcanoes, but the plate tectonics at work underneath don't stop there. The ring of fire is also the site of 81% of the world's major Earthquakes and 90% of the world's total earthquakes.
Earth's Atmosphere Composed of Tectonic Plates
To understand why there is so much activity and why it is in this particular region, it is necessary to know two things: First, the Earth's lithosphere is composed of large slabs of rock named tectonic plates on which the surface of the Earth sits. Second, these plates move and shift. Though the ring of fire was labeled before these two facts were studied, plate tectonics can explain what causes the seismic activity present.
Where tectonic plates meet is call a boundary zone, and the ring of fire is basically a series of these zones. As the meeting plates adjust they interact with one another in a series of possible ways:
- Transform Boundaries ' where plates grind past each other
- Divergent Boundaries ' where plates slide apart from each other
- Convergent Boundaries ' where two plates moves towards one another causing either a continental collision or subduction.
We are mainly concerned about subduction zones, as these are the zones where volcanoes are most likely.
In the process of subduction, one plate moves beneath another plate. As the rock of the subducting plate moves downward, towards the Earth's mantle, water is released. This super hot water moves upward towards the Earth's surface, melting rock into magma. This magma in turn continues the upward journey and can cause the formation and eruption of volcanoes.
Many of the boundary zones around the ring of fire are volatile subduction zones, examples of which are the Cocos Plate being subducted beneath the South American Plate and the Pacific Plate being subduced beneath the north American Plate.
Notable volcanoes created in this process around the Ring of Fire are Mt St. Helens and Mt. Fuji.
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