
What is the Pacific ‘Ring of Fire’?
Feb 24, 2022
What is the Pacific ‘Ring of Fire’?
Q Why is it in News ?
A The Hunga Tonga-Hunga Ha’apai volcano which massively erupted lies along the Pacific ‘Ring of fire’, and is just over 60 kilometers from the island nation of Tonga.
Q What is the Pacific ‘Ring of Fire’?
A
- The Pacific ‘Ring of Fire’ or Pacific rim, or the Circum-Pacific Belt, is an area along the Pacific Ocean that is characterized by active volcanoes and frequent earthquakes.
- Volcanic arcs and oceanic trenches partly encircling the Pacific Basin form the so-called Ring of Fire.
- It is home to about 75 per cent of the world’s volcanoes – more than 450 volcanoes.
- Also, about 90 per cent of the world’s earthquakes occur here.
Q How much is Its spread ?
A
- Its length is over 40,000 kilometres and traces from New Zealand clockwise in an almost circular arc covering Tonga, Kermadec Islands, Indonesia.
- It is moving up to the Philippines, Japan, and stretching eastward to the Aleutian Islands, then southward along the western coast of North America and South America.
Q What is the extent of Seismic activity of the region ?
A
- The area is along several tectonic plates including the Pacific plate, Philippine Plate, Juan de Fuca plate, Cocos plate, Nazca plate, and North American plate.
- The movement of these plates or tectonic activity makes the area witness abundant earthquakes and tsunamis every year.
- Along much of the Ring, tectonic plates move towards each other creating subduction zones.
- One plate gets pushed down or is subducted by the other plate.
- This is a very slow process – a movement of just one or two inches per year.
- As this subduction happens, rocks melt, become magma and move to Earth’s surface and cause volcanic activity.
Q What has happened in recent eruption in Tonga?
A
- In the case of Tonga, the Pacific Plate was pushed down below the Indo-Australian Plate and Tonga plate, causing the molten rock to rise above and form the chain of volcanoes.
- Subduction zones are also where most of the violent earthquakes on the planet occur.
- The December 26, 2004 earthquake occurred along the subduction zone where the Indian Plate was subducted beneath the Burma plate.