Antique lava crystals, which once erupted from volcanoes, may finally reveal secrets about when these violent explosions may next occur, researchers have announced. Volcanologists analysed crystals formed inside porous rock spewed from Hawaii’s Kīlauea volcano upon its 1959 eruption.
And the volcano experts believe these crystals’ usual shape, when paired with cutting-edge computer simulations, can forecast eruptions.
Professor Jenny Suckale of Stanford Earth, said: ”We can actually infer quantitative attributes of the flow prior to eruption from this crystal data and learn about the processes that led to the eruption without drilling into the volcano).”
She added: “That to me is the Holy Grail in volcanology.”
The almost microscopic-sized crystals were discovered entombed in lava after Kilauea’s eruption.
An analysis of the crystals revealed they were oriented in an odd and unexpectedly consistent pattern.
The Stanford researchers thought these patterns were created by a wave within the subsurface magma, affecting the direction of the crystals in the flow.
And the volcanologists have now managed to simulate this physical process for the first time.
Professor Suckale, the study’s senior author, said: “I always had the suspicion that these crystals are way more interesting and important than we give them credit for.”
The assistant professor of geophysics was prompted to act on a hunch after by chance listening to a presentation about the ocean’s microplastics.
Waves can cause non-spherical particles to assume a consistent misorientation pattern.
Professor Suckale recruited the speaker, then-PhD student Michelle DiBenedetto, to see if the theory could be applied to the unusual crystal orientations originated from Kilauea.
The researchers analysed crystals from the dark, porous scoria rock that forms upon the cooling of magma containing dissolved gases.
Following a volcanic eruption, the liquid magma – called lava when it spews to the surface – is shocked by the cooler atmospheric temperature.
Consequently, it quickly traps the naturally-occurring olivine crystals and bubbles inside.
The process happens so rapidly the crystals cannot grow, thereby creating a time capsule of sorts detailing what happened during an eruption.
The new simulation is based on crystal orientations from Kilauea Iki, a pit crater next to Kilauea Volcano’s main summit caldera.
This is believed to provide a baseline for understanding the flow of Kilauea’s conduit, the passage through which red-hot magma rises to the surface.
Because the scoria can be blown hundreds of metres from the volcano, these samples were relatively easy to collect.
Dr DiBenedetto, said: ”It’s exciting that we can use these really small-scale processes to understand this huge system.”
In order to remain liquid, the molten rock within a volcano needs to be in constant flux.
The team’s analysis indicates the odd alignment of the crystals was caused by magma moving in two directions at once, with one flow directly atop the other, rather than pouring through the conduit in one steady stream.
Monitoring Kilauea presents major difficulties because of the active volcano’s unpredictable eruptions.
Instead of leaking lava continuously, Kilauea instead has periodic eruptions resulting in dangerous lava flows.
An unprecedented eruption of Kīlauea, which is one of Hawaii’s most active volcanoes, destroyed more than Big Island 500 homes in 2018.
Although Kīlauea has been erupting continuously for decades, the eruption in the Puna district entered an extraordinary new phase this year.