VOLCANOES AND EARTHQUAKES

Why did rocks melt ?

Tectonics plaques move and they create a space among themself ,and the hot rock that is behind they ,go up .And when it go ups ,the pressure on the rock decreases.this process happens in oceanic -center dorsal ,a mountainous submarine system.

hOW DOES AN ERUPtION OCCUR?

We call volcanic eruption to the violent expulsion of material proceeding from the interior of a planet (the Earth) on the surface of the Earth.

This expulsion takes place as consequence of the acumulated gas , warm rocks, ash and incandescent material inside the Earth throughout years.

The consequent pressure makes that all this accumulation is liberated towards the surface, the pressure inside the Earth can accumulate for many years (up to hundreds, or enclosed thousands).

It is named a magma when material is in the deep of the Earth, but once it is expelled towards the surface and begins to cool, hardening, we called it lava.

The volcanic eruptions are related to the movement of the tectonic plates. These changes in the tectonic plates produce big movements of magma and generate pressure towards the bark.

When the magma flows and raises the sufficient thing as to come to the surface, there drags the rocks that it finds to its step and is fusing them, which added to the gases (that believe a great pressure from below up) can produce a very violent eruption.

PILOW LABA

It occurs when a volcano exploit under the water and the lava comes up and it form a new continental crust.

When the pilow lave it comes to the surface of the sea, since there is a incredible change of temperature, between the lava and the water, the surface of the language cool very fast, forming a bark.

The pilow lava is formed mainly of basalt, in spite of some pilow lava are formed of another minerals, for example: comatita, andresita…

The pilow lava of Barrika are formed of ofita and their mineral is olibino.