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12/22/2024 08:03:15 pm

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Scientists Discover How the Earth's Crust is Formed

Bardabunga

(Photo : Reuters) Confirming fears, Iceland's Bardabunga volcano is now actively erupting.

Scientists have gained more insight into how the Earth's crust forms from data obtained by a research team that studied an erupting Icelandic volcano.

Last August, a swarm of about 1,600 earthquakes with magnitudes of 4.5 hit Iceland in 48 hours.

It was an indication that the second highest mountain in Iceland and buried under the Iceland's Vatnajokull ice cap, Barðarbunga, was about to erupt. Since then, people have been evacuated due to the continual eruption of the volcano.

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Scientists, however, have observed how the Earth's crust forms because of this phenomenon. They observed that molten rock forms vertical sheet-like features known as dykes. These dykes force surrounding rocks apart.

Professor Andy Hope from the Center of Observation and Modelling of Earthquakes, volcanoes and Tectonics (COMET) is the co-author of the study.

He explains that new crust forms whenever two tectonic plates move away from each other. This mostly happens beneath the ocean where it's hard to observe.

In Iceland, this happens beneath dry land. The events leading to the eruption in August 2014 are the first time such a rifting episode has occurred there and been observed with modern tools, like GPS and satellite radar.

The dyke then grows in segments and breaks through from one to the next by the build-up of pressure.

This spectacle explains how focused upwelling of magma under central volcanoes is redistributed over large areas of land, effectively creating a new upper crust at divergent plate boundaries.

Apart from the dykes, the team also found ice cauldrons or shallow depressions in the ice with circular crevasses where the base of the glacier has been melted by magma.

From these findings, scientists discovered why magma from a volcano travels in such a roundabout path into the Earth's crust.

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