Several factors trigger volcanic eruptions, including the buoyancy of magma, a build-up of pressure from the gases in the magma and an injection of new magma into a full magma chamber.
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 dissolved gases it contains are discharged.
A volcano begins as melted rock (magma) which rises from deep inside the earth
toward the surface. As the gas-filled magma rises ...
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
Volcanoes erupt due to pressure that the weight of the rocks puts on the magma
and forces it to the surface out any available vent or exit provided to it.
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 ...
A secondary school revision resource for GCSE Geography covering key facts
about volcanoes and volcanic eruptions.
Some volcanic eruptions are explosive and other are not. How explosive an
eruption is depends on how runny or sticky the magma is. If magma is thin and ...
There are few geological events that are as dramatic as a volcanic eruption
except maybe a hurricane, tornado or a tsunami. Each is drama.
May 26, 2016 ... Volcanic eruptions are driven by a combination of mechanisms, which ... The
crust makes up a tiny volume of the Earth, ranging from 10 km in ...
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.