Living with volcanoes

Farming

A major reason why so many people (around 8 per cent of the world’s population) live so close to volcanoes is the fertile soils that are found on and around them, making them some of the most agriculturally productive areas on Earth.

Ash and lava decompose and bond with organic matter to create nutrient rich soil. The soil is also low density, porous and good at storing water, perfect for growing crops.

Image: Rice terraces near Mt. Agung, Bali, Indonesia.

Geothermal power

The heat beneath the Earth in volcanic regions can be exploited to generate electricity. Wells drilled deep into rock are filled with water that is heated by magma close to the surface. The hot water is piped to homes and the steam is used to turn turbines that generate electricity.

Iceland generates 30 per cent of its electricity from geothermal power. Surplus mineral-rich water from the power plants is used to fill geothermal swimming pools.

Rare minerals, from which we make supermagnets, are found in some types of igneous rock (solidified magma), but there are only a few locations around the world where they are concentrated enough to make mining financially worthwhile.

Supermagnets are used in technology as diverse as mobile phones, loud speakers and electric guitars.

Another mineral found in some volcanic areas is eudialyte, used to create zirconium, a rare metal that is heat and corrosion resistant and is used in nuclear reactors and the space industry.

Image: an employee at a machinery plant in Japan shows rare earth magnets.

Mining

Volcanoes and the area around them are a rich source of valuable minerals such as sulphur, copper and diamonds that can bring economic benefits to people and governments.

The benefits of mining have to be balanced against the negative impacts, because mining scars the landscape and the refinement process can release radioactivity and pollute the surrounding environment.

Image: mining sulphur from a volcanic crater in Indonesia.