Volcanoes erupt because of density and pressure. The lower density of the magma relative to the surrounding rocks causes it to rise (like air bubbles in syrup).
A volcano begins as melted rock (magma) which rises from deep inside the earth toward the surface. As the gas-filled magma rises ...
When a part of the earth's upper mantle or lower crust melts, magma forms. A volcano is essentially an opening or a vent through which this magma and the ...
Nov 17, 2016 ... In a volcanic eruption, super-heated magma from within the earth's upper ... while last week's episode focused on what causes a wildfire.
Find out what the earth make-up is, and how extreme pressure build up inside the ... molten matter to be expelled out to the surface, causing a volcanic eruption.
Jan 6, 2016 ... A team of volcanologists led by the University of Liverpool have released a perhaps controversial Nature study on the causes of volcanic ...
Jan 5, 2015 ... The eruption of a volcano can be one of the planet's most destructive events — spewing huge amounts of rock, gas and ash that can kill people.
A secondary school revision resource for GCSE Geography covering key facts about volcanoes and volcanic eruptions.
Feb 22, 2017 ... They make headlines when they rumble, and when spew their fire and ash; they make an amazing sight, a phenomenon that piques the ...