Scientists shine light on tiny crystals behind unexpected violent eruptions

Scientists shine light on tiny crystals behind unexpected violent eruptions
In a new study of volcanic processes, Bristol scientists have demonstrated the role nanolites play in the creation of violent eruptions at otherwise calm and predictable volcanoes.


The study, published in Science Advances, describes how nano-sized crystals (nanolites), 10,000 times smaller than the width of a human hair, can have a significant impact of the viscosity of erupting magma, resulting in previously unexplained and explosive eruptions.

"This discovery provides an eloquent explanation for violent eruptions at volcanos that are generally well behaved but occasionally present us with a deadly surprise, such as the 122 BC eruption of Mount Etna," said Dr Danilo Di Genova from the University of Bristol s School of Earth Sciences.

"Volcanoes with low silica magma compositions have very low viscosity, which usually allows the gas to gently escape. However, we ve shown that nanolites can increase the viscosity for a limited time, which would trap gas in the sticky liquid, leading to a sudden switch in behaviour that was previously difficult to explain."

Dr Richard Brooker also from Earth Sciences, said: "We demonstrated the surprising effect of nanolites on magma viscosity, and thereby volcanic eruptions, using cutting-edge nano-imaging and Raman spectroscopy to hunt for evidence of these almost invisible particles in ash erupted during very violent eruptions."

"The next stage was to re-melt these rocks in the laboratory and recreate the correct cooling rate to produce nanolites in the molten magma. Using the scattering of extremely bright synchrotron source radiation (10 billion times brighter than the sun) we were able to document nanolite growth."

"We then produced a nanolite-bearing basaltic foam (pumice) under laboratory conditions, also demonstrating how these nanolites can be produced by undercooling as volatiles are exsolved from magma, lowering the liquidus."

Professor Heidy Mader added: "By conducting new experiments on analogue synthetic materials, at low shear rates relative to volcanic systems, we were able to demonstrate the possibility of extreme viscosities for nanolite-bearing magma, extending our understanding of the unusual (non-Newtonian) behaviour of nanofluids, which have remained enigmatic since the term was coined 25 years ago."

The next stage for this research is to model this dangerous, unpredictable volcanic behaviour in actual volcanic situations. This is the focus of a Natural Environment Research Council (UK) and National Science Foundation (US) grant Quantifying Disequilibrium Processes in Basaltic Volcanism awarded to Bristol and a consortium of colleagues in Manchester, Durham, Cambridge and Arizona State University.

Materials provided by University of Bristol . Note: Content may be edited for style and length.

University of Bristol. "Scientists shine light on tiny crystals behind unexpected violent eruptions." ScienceDaily. ScienceDaily, 23 September 2020. .

University of Bristol. "Scientists shine light on tiny crystals behind unexpected violent eruptions." ScienceDaily. (accessed September 24, 2020).



Oct. 11, 2019 — A new study describes how spheres can be transformed into twisted spindles thanks to insights from 16th century navigational tools. Researchers show how polymers can contract into spiral structures, ...

Oct. 23, 2017 — Zircon crystals in igneous rocks must be carefully examined and not relied upon solely to predict future volcanic eruptions and other tectonic events, researchers have ...

Aug. 23, 2017 — The world s shortest race by distance -- a fraction of the width of a human hair -- was a huge success for scientists working at the nanoscale. It spurred interest in molecular machines and led ...

Sep. 28, 2016 — Scientists have measured the mechanics of tiny crystalline ceramics. Materials are made of atoms, and if they are arranged periodically, they are called crystalline structures. If the size of these ...
News Topics :
Volcanoes are not fed by molten magma formed in large chambers finds a new study, overturning classic ideas about volcanic eruptions. advertisement Instead, the study suggests that volcanoes are fed...
Close Research shedding light on the internal plumbing of volcanoes may help scientists better understand volcanic eruptions and unrest. advertisement The University of Queensland led study analysed crystals in Italy s...
Uplifting of Columbia River basalts has allowed University of Oregon researchers to better understand of how magma 14 16 million years ago shaped the region and why greenhouse gases released during...
The molten rock that feeds volcanoes can be stored in the Earth s crust for as long as a thousand years, a result which may help with volcanic hazard management...
In a new study, published in the journal Nature, an international team of scientists provide the first conclusive evidence directly linking deep Earth s water cycle and its expressions with...