'Zombie' volcano dormant for 250,000 years awakens as scientists warn of eruption

A volcano that has not erupted in 250,000 years is showing signs of an imminent eruption that would cause destruction and loss of life.

Uturuncu, a so-called 'zombie' volcano located in the Andes Mountains of Bolivia, has experienced increased seismic activity and gas emissions.

This unrest is visible in a distinctive 'sombrero' pattern of ground deformation, where the land at the center of the volcano is rising while the surrounding area is sinking.

A team of scientists led by the University of Oxford in the UK discovered that this activity is due to the movement of liquid and gas beneath the crater, which sits above the largest known magma body in the Earth's crust.

Uturuncu stands over 19,700 feet high and is a stratovolcano—a large, steep, cone-shaped volcano built up by layers of hardened lava, volcanic ash and rock.

Mount St. Helens and Mount Vesuvius are also stratovolcanoes known for their catastrophic eruptions.

Uturuncu lies within 25 miles of three towns, and an eruption could cause widespread damage and pose a serious threat to life, researchers warned. It is about halfway between two major cities in South America, La Paz in Bolivia and Santiago in Chile.

Lava flows would engulf these nearby communities, while volcanic ash could spread across Bolivia, Argentina and Chile.

More than 1,700 earthquakes have been detected around the volcano recently, leading scientists to study Uturuncu and determine how a dead volcano could come back to life.

The research team used seismic tomography, a technique similar to medical scans, to create images of the inside of the volcano.

By studying how seismic waves move through different materials, they were able to build a detailed 3D view of Uturuncu's interior.

They also looked at the volcano's physical makeup, including the types of rocks, to better understand what's happening underground.

Their analysis revealed possible paths where hot fluids are moving upward and where gases and liquids are gathering in chambers beneath the crater.

The scientists believe this buildup is likely causing the ground in the center to rise—but they said the chances of a full eruption are still low.

Co-author Professor Matthew Pritchard from Cornell University said: 'The methods in this paper could be applied to the more than 1400 potentially active volcanoes and to the dozens of volcanoes like Uturuncu that aren't considered active but that show signs of life — other potential zombie volcanoes.'

California's Long Valley Caldera, a supervolcano, is also deemed a 'zombie' volcano as it last erupted more than 550 years ago.

As is the Yellowstone Caldera that is closely monitored by scientists.

'The most recent volcanic activity at Yellowstone consisted of rhyolitic lava flows that erupted approximately 70,000 years ago,' according to the US Geological Survey (USGS).

'The largest of these flows formed the Pitchstone Plateau in southwestern Yellowstone National Park.'

One of the most famous volcanoes on Earth, Yellowstone is located beneath a national park spanning three states – Idaho, Wyoming and Montana.

While scientists are unsure if the two volcanoes in the US will ever erupt, they are preparing for Mount Spurr to blow.

In March, Alaskan officials warned it could erupt in the next few weeks or months after observing increase seismic activity, ground deformation and gas emission.

Mount Spurr also sits about 78 miles from Anchorage, home to nearly 300,000 people, which would be blanket in thick volcanic ash.

In a Thursday updated, the Alaska Volcano Observatory (AVO) said 'unrest continues,' as 'frequent small volcanic earthquakes were detected beneath the volcano over the past day.'

The eruption will set of a chain reaction that would cause international chaos.

A massive cloud of ash billowing 50,000 feet into the air would force international hubs such as Ted Stevens Anchorage International Airport (ANC) and potentially Fairbanks International Airport (FAI) to shut down.

Halting all incoming and departing flights at these airports could have a ripple effect across the country, resulting in widespread delays and cancellations and even disrupting the global supply chain.

Hundreds of planes fly over Anchorage and Fairbanks per day, and it's not just passenger flights that would be impacted. ANC is the fourth-busiest cargo airport in the world, with more than 8,000 cargo flights passing through each month.

Then last time Mount Spurr erupted in 1992, ANC shut down for 20 hours while the ash cloud hung over Anchorage. It darkened skies in the middle of the day, and ultimately settled an eighth of an inch thick across the city.

When Mount Spurr blows, the resulting ash cloud will pose a significant hazard to airplanes because the particles are highly abrasive.

Flying through an ash cloud can quickly damage windscreens, fuselage surfaces, compressor fan blades and even kill the plane's engine. Ash particles can also cause critical navigational and operational instruments to fail.

All of this means that it is extremely dangerous to fly a plane while a volcanic eruption is occurring nearby. So, all airports in areas affected by the ash cloud will have to shut down.