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Birth of an Island

Plate tectonics

 Automatic translationAutomatic translation Category: volcanoes
Updated June 01, 2013

The tectonic plates (initially called continental drift) is the current model of the internal functioning of the Earth. The oceanic plates are located at the Mid Ocean wrinkles. At these places, the oceanic crust is very thin, a few kilometers thick lava happens to clear a permanent move to the surface through large cracks long thousands of kilometers.
These cracks, called rift ocean is filled with lava that cools getting closer to the area in contact with water.
The lava then crystallize on each wall of the crack, making the new oceanic crust by removing the crust the oldest.

 

This is done to gauge the speed of a few centimeters per year on average and thus Europe and North America were joined there almost 150 million years, were at a distance of another.

Image: The main tectonic plates, bounded by the lines of earthquakes.
The plate of North America, South America, of Eurasia, Africa, the Pacific, Australia and Antarctica.

 main tectonic plates, bounded by the lines of earthquakes

Underwater volcanic eruption

    

Surtsey is a volcanic island created off the coast of Iceland, the Westman Islands archipelago.
Eighty volcanoes seventeen aircraft, including Surtsey, the system consists of volcanic Westman Islands.
It was formed quickly, following a series of volcanic eruptions underwater.
The first eruption began 130 meters below the Wed, November 10th, 1963, the island of Surtsey emerged from Icelandic waters 14 November 1963 and has spread to the surface of the water for only four years. The nouvell73 meters.
Upon apparitions Surtsey as 1.41 km2 and has a height of 1, the island is closed to the public, only scientists are allowed to attend.
The island of Surtsey is a World Heritage Site of UNESCO since 2008.

 Surtsey in 1999

Image: the island of Surtsey in 1999.

Image: birth of the Icelandic island of Surtsey is out of the waters in November 1963. credit: University of Colorado

 born in the island Surtsey Isalnde

Eruption of Tonga Islands

    

Tonga Islands region is prone to volcanic eruptions underwater forever.
This is due to plate tectonics as these islands are actually located on the Pacific Ring of Fire where earthquakes and volcanoes accumulate.
The Pacific plate moves closer to the Australian plate at an average speed of 7.7 centimeters per year.
On Thursday, March 19, 2009 at 8 am local 17 (20H17 UTC), an earthquake of magnitude 7.9 hit the Tonga islands and a spectacular volcanic eruption occurred off the coast of Tongatapu island, located precisely on the Ring of Fire in the South Pacific. A swell from west to east through the French Polynesia has three hours later, said the High Commission in French Polynesia. Low elevations of sea level were recorded, 18 cm and 20 cm at Papeete to Nuku Hiva in the Marquesas.
Tahiti lies 8 478 miles from Tonga.

 

Image: The epicenter of the quake was located 210 km from Nukualofa, the capital of Tonga, and 480 km of the islands Ndoi in Fiji at a depth of 10km.

 eruption off the Tonga Islands, March 2009
 
           
Disaster of great eruption
 
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