A team of scientists may have developed a new method of predicting potentially deadly eruptions, by studying tiny crystals contained in volcanic debris. In the future, the research could provide greater warning, and so more evacuation time to at-risk populations, and help mitigate other disruptive side-effects of volcanic eruptions.
Volcanoes serve as awe-inspiring reminders of the potent geological processes that are taking place beneath the Earth's surface. They have the capacity to dramatically alter our lives, not to mention the very nature of the planet that we inhabit.
Underwater volcanoes have been known to create entire islands, and their surface counterparts have the ability to significantly alter our atmosphere by spewing vast plumes of material miles into the sky. In the face of this destructive potential, those living near a volcano can only flee at the first sign of danger, and so early warning systems are paramount to stemming the loss of life from an eruption.
The newly published research focuses on an analysis of tiny crystals that formed in magma as it flowed toward the Earth's surface from depths of up to 30 km (18.6 miles) below the famous Sicilian volcano, Mount Etna. As the crystals traveled, they grew larger, and their composition altered. These changes formed records of the processes leading up to a number of eruption events in growth layers similar in nature to the rings of a tree.
Having journeyed to the surface, the crystals were expelled from Mount Etna, and carried away in volcanic materials that quickly hardened into rock. The volcanologists conducting the study employed a technique known as laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) to study the crystals.
The technique uses a laser to remove fine particles from the volcanic samples, which are then ionized and introduced to a mass spectrometer that analyses the elemental and isotopic characteristics of the material.
The results of the study analysis revealed that when new magma arrived at a depth of 10 km (6.2 miles) below Mount Etna, there was a 90 percent chance that an eruption would be triggered within a two-week period.
"In this case, therefore, earth tremors at the depth of magma recharge must be taken as serious signs of potential imminent eruptions" states Dr. Teresa Ubide, a volcanologist at the University of Queensland, and co-author of a paper detailing the research. "At other volcanoes, the method will allow to establish the relationship between recharge depth, recharge frequency and eruption efficiency. This can then help scientists to better relate physical signs of recharge to eruption potential."
The new early warning technique could even prove useful in forecasting dangerous events in volcanoes that have lain dormant for a prolonged period of time, meaning there is no eruption data. In these cases, the researchers would simply need to collect samples from historic volcanic outbursts in order to establish a relationship between magma activity and a potential eruption. If such activity were detected beneath the volcano, the order could be given to clear the area.
Moving forward, the team members intend to apply their research to other volcanoes, predominantly in the areas surrounding Australia, such as Indonesia and New Zealand.
A paper detailing the research has been published in the journal Nature Communications.
Source: Trinity College Dublin
