In the last century, just four eruptions—three in the Caribbean and one in Colombia—ended the lives of some 67,000 people. The destructive capacity of volcanoes is indisputable, but these giants of nature also have a much friendlier face that often goes unnoticed.
Their geological and biochemical activity generates the necessary ingredients for life and fosters the development of different animal species. In addition, this source of energy is useful for humans, since it is the foundation of geothermal energy.
The Romans were already using the fireproof and resistant properties of volcanic products to build concrete two millennia ago, and today we continue to employ them in a myriad of materials, from bricks to lithium devices.
Fountain of life
In a conversation with OpenMind, Ceridwen Fraser, a professor at the Fenner School for the Environment and Society, Australian National University, says: “There is now goodevidence that volcanoes can support life and some people even think that life on Earth probably originated around them.”
The academic is referring to the activity of the underwater hydrothermal chimneys, where it is suggested that life could have begun. Although sunlight barely reaches these depths, today different species, such as crabs or anemones, use the chemicals generated by the vents as a source of energy.
“This chemical energy comes from hydrogen sulphide, iron, methane, hydrogen and other elements and molecules. This makes the microbes and animals associated with submarine volcanoes much different than those in the rest of the ocean that get their energy from sunlight or feed on organisms that ultimately derive their energy from the Sun” explains Joseph Resing, a research fellow at the Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington, to OpenMind.
The scientist and his team have shown how the iron emitted by the underwater volcanoes of the Eastern Pacific ridge, instead of being deposited in the vicinity, as was previously thought, is transported by the marine currents and nourishes the phytoplankton that, in turn, feeds hundreds of species.
Out of the water, but in an equally inhospitable environment, that of Antarctica, Fraser has discovered that volcanoes, with their steam and heat, allowed many plants and animals to survive different glacial periods.
From Roman concrete to lithium batteries
In addition to being a source of life, magmatic material and minerals ejected during eruptions have direct applications for humans. The Romans, for example, used ash and volcanic rocks to produce their indestructible concrete, with which they built the Pantheon of Rome (Italy), among other buildings.
Today, basalt ash is used as cement filler and also to manufacture bricks, tiles and panels, as volcanic rock is a fireproof material, resistant to corrosion and crushing. Basalt fibre, being elastic and having insulating properties, is widely used in fire fighting and also in aviation, the armament industry and the automobile industry.
Alongside these applications, a few months ago a team of researchers pointed out the potential of supervolcanoes in the development of batteries and other lithium-based products. This would be another way of obtaining this chemical element discovered in the nineteenth century and whose main deposits are found in different salt flats in Bolivia, Chile and Argentina.
Supervolcanoes are characterized by their enormous holes caused by the collapse of the magmatic chamber after the violent eruption. These cavities fill with water and form lakes where lithium accumulates in a kind of clay.
To identify which supervolcanoes have the best lithium sources, the scientists analysed small fragments of magma trapped in crystals during their growth inside the chamber. The team analysed tectonic environments in the United States, Mexico and Italy and found that lithium concentrations varied greatly.
Its presence depends on whether the supervolcano is large enough, has a huge lake on its caldera and has formed from the thick continental crust, rich in lithium.
“They need to have some sort of relatively low-temperature geothermal system (such as geysers) to form clays that incorporates lithium into their structures,” explains Thomas R. Benson, a researcher at the Department of Geological Sciences at Stanford University and lead author of the research, which is published in the journal Nature Communications.
Geothermal energy motor
This same geothermal activity is very useful as an energy source. The areas near the edges of the tectonic plates, where most eruptions and earthquakes occur, are rich in geothermal energy and an ideal place to locate such power stations.
The activity originates from molten magma and from the disintegration of radioactive substances. The groundwater is heated and comes to the surface in the form of thermal springs or geysers. “Volcanic centres have been used for geothermal energy for centuries, even earlier than for thermal baths,” Benson points out.
In addition to the energy sector, volcanoes are also important for another industry worth millions: jewellery. Gemstones like sapphires, rubies and diamonds are transported to the surface thanks to volcanic eruptions. For those who dig these stones from the ground, volcanoes are an inexhaustible source of wealth.