Scientists predict volcanic eruptions by looking at lava crystals decades old



Lava crystals that erupted from volcanoes more than half a century ago may reveal secrets as to when they might erupt next, a new study claims.

American scientists analyzed crystals formed in a type of porous rock that erupted from the Kīlauea volcano in Hawaii in 1959.

The crystals had a strange shape that, along with computer modeling simulations, can predict future and potentially fatal eruptions, the experts say.

Although crystals were taken from the 1959 Kīlauea eruption, the volcano is still active and destroyed more than 500 homes when it erupted in 2018.

A lava fountain during the 1959 Kilauea Iki eruption - a well crater next to the main peak of the Kīlauea caldera

A lava fountain during the 1959 Kilauea Iki eruption – a well crater next to the main peak of the Kīlauea caldera

“I’ve always suspected that these crystals are much more interesting and important than we call them,” said study author Jenny Suckale, an assistant professor at Stanford’s School of Earth, Energy & Environmental Sciences.

We can actually infer quantitative characteristics of the pre-eruption current from this crystal data and learn about the processes that led to the eruption without drilling into the volcano.

“For me, that is the holy grail in volcanology.”

Scientists who want to understand how and when volcanoes can erupt are hampered by the fact that many of the volcanic processes responsible for it take place deep underground.

An eruption often destroys any underground markers that might have provided clues to an explosion.

The Kīlauea volcano is located on the southeast side of the island of Hawaii, also known as the Big Island.  The island of Hawaii is the largest island in the US state

The Kīlauea volcano is located on the southeast side of the island of Hawaii, also known as the Big Island. The island of Hawaii is the largest island in the US state

But volcanic crystals can help test computer models of magma flow, which can reveal insights about past eruptions and help predict possible future eruptions.

KILAUEA VOLCANO: THREE MONTHS OF CHAOS IN 2018

The Kilauea volcano on Hawaii’s Big Island has been erupting for over 30 years, but it bubbled up in May 2018 after the volcano’s summit rose in the weeks before.

In the years before, the volcano mainly released lava in hard-to-reach areas in a national park or along the island’s coastline.

Lava from the bubbling volcano has now destroyed more than 600 homes and forced nearly 2,000 residents to evacuate.

Researchers who followed the event said there was no indication when the destructive lava flow would stop.

By early August, the eruption had almost completely disappeared and on December 5 it was declared to have ended after three months of inactivity.

The Stanford team analyzed crystals from scoria, an igneous rock – meaning it was formed by the cooling and solidification of magma or lava.

Scoria is dark in color and consists of round bubble-like cavities known as blisters.

Blisters form when gases dissolved in the liquid magma – known as lava once it reaches the surface – escape during eruption, creating bubbles as the rock cools and solidifies.

These vesicles can be empty, but sometimes they contain tiny natural crystals.

Vesicles form so quickly that any crystals inside cannot grow, effectively recording what happened during the eruption.

Researchers studied millimeter-sized crystals, consisting of a mineral called olivine, discovered after the chaotic eruption of Kilauea volcano in Hawaii in 1959.

Since the snails can be blown several hundred yards away from the volcano, these samples were relatively easy to collect.

Analysis of the crystals revealed that they were oriented in a ‘strange but surprisingly consistent’ pattern.

This could be due to a wave in the underground magma affecting the direction of the crystals in the flow.

Researchers simulated this physical process for the first time using computer modeling.

Close-up of scoria, a dark igneous rock made up of round, bubble-like cavities known as vesicles

Close-up of scoria, a dark igneous rock made up of round, bubble-like cavities known as vesicles

Professor Suckale was originally inspired by Michelle DiBenedetto, a Stanford expert in fluid dynamics, whose work had focused on the transport and behavior of non-spherical microplastic particles in waves.

Professor Suckale recruited DiBenedetto to see if the theory could be applied to the strange crystal orientations of Kilauea Iki, a well crater next to the main peak of Kilauea volcano.

Simulations provided a basis for understanding the flow of Kilauea’s tube, the tubular passageway through which hot magma rises underground to Earth’s surface.

In order to remain fluid, the material in a volcano must be constantly in motion.

The team’s analysis indicates that the strange alignment of the crystals was caused by magma moving in two directions at once, with one stream directly on top of the other, rather than pouring through the conduit in a steady stream.

Lava flows into a lava crevice in the wake of eruptions from Kilauea volcano on Hawaii's Big Island, on May 12, 2018 in Pahoa, Hawaii

Lava flows at a lava crevice in the wake of eruptions from Kilauea volcano on Hawaii’s Big Island on May 12, 2018 in Pahoa, Hawaii

Investigators had previously speculated that this could happen, but a lack of direct access to the molten lead prevented convincing evidence, Suckale said.

“This data is important for furthering our future research on these hazards because if I can measure the wave, I can limit the flow of magma – and with these crystals I can get to that wave,” said Professor Suckale.

Monitoring Kilauea from a hazard perspective is an ongoing challenge due to the active volcano’s unpredictable eruptions.

Rather than continuously leaking lava, it has periodic eruptions that result in lava flows that endanger the residents on the southeast side of Hawaii’s largest island, which is also known as Hawaii but also referred to as the Big Island.

An unprecedented eruption of Kīlauea, one of Hawaii’s most active volcanoes, destroyed more than 500 homes in 2018.

Although Kīlauea has been erupting continuously for decades, the eruption in Puna district entered an extraordinary new phase on May 3, 2018.

Glowing lava was shot nearly sixty feet into the sky and spread over 13 square miles across the densely populated east coast of Hawaii’s largest island.

The Hawaiian government reported high levels of toxic sulfur dioxide in the area, affecting some of the first responders.

Power lines are said to have melted from poles due to the heat, while other reports describe lava flows flowing through forests and over roads.

By tracking the misorientation of crystals at the different stages of future Kilauea eruptions, scientists could infer cond out flow conditions over time, the researchers say.

“No one knows when the next episode will start or how bad it is going to get – and it all depends on the details of the leadership dynamics,” Suckale said.

The study is published in Science Advances.

VOLCANIC FAILURE INDICATORS CAN HELP FORECAST

According to Eric Dunham, associate professor at Stanford University’s School of Earth, Energy and Environmental Sciences, “Volcanoes are complicated and there is currently no universally applicable way to predict eruptions. In all likelihood, that will never happen. ‘

However, there is evidence of increased volcanic activity, which researchers can use to predict volcanic eruptions.

Researchers can track indicators such as:

  • Volcanic infrasound: When the lava lake rises into the crater of an open volcano, a sign of a possible eruption, the pitch or frequency of the sounds generated by the magma tends to increase.
  • Seismic activity: Prior to an eruption, seismic activity in the form of small earthquakes and tremors almost always increases as magma moves through the volcano’s “ plumbing system. ”
  • Gas emissions: As magma approaches the surface and the pressure decreases, gases escape. Sulfur dioxide is one of the major components of volcanic gases, and increasing amounts of it are a sign of increasing amounts of magma near the surface of a volcano.
  • Bottom deformation: Changes in a volcano’s ground surface (volcano deformation) appear as swelling, sinking, or cracks, which can be caused by magma, gas, or other liquids (usually water) moving underground or by movements in the Earth’s crust due to movement along a fault lines. Swelling of a volcano can indicates that magma has accumulated near the surface.

Source: Geological Survey of the United States


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