Date:

Cluster of Alaskan Islands Could be a Super Volcano

Scientists suggest that a small group of volcanic islands in Alaska’s Aleutian chain might be part of a single, undiscovered giant volcano.

If the researchers’ suspicions are correct, the newfound volcanic caldera would belong to the same category of volcanoes as the Yellowstone Caldera and other volcanoes that have had super-eruptions with severe global consequences.

- Advertisement -

The Islands of the Four Mountains in the central Aleutians is a tight group of six stratovolcanoes named Carlisle, Cleveland, Herbert, Kagamil, Tana and Uliaga. Stratovolcanoes are what most people envision when they think of a volcano: a steep conical mountain with a banner of clouds and ash waving at the summit. They can have powerful eruptions, like that of Mount St. Helens in 1980, but these are dwarfed by far less frequent caldera-forming eruptions.

Researchers from a variety of institutions and disciplines have been studying Mount Cleveland, the most active volcano of the group, trying to understand the nature of the Islands of the Four Mountains. They have gathered multiple pieces of evidence showing that the islands could belong to one interconnected caldera.

Unlike stratovolcanoes, which tend to tap small- to modestly-sized reservoirs of magma, a caldera is created by tapping a huge reservoir in the Earth’s crust. When the reservoir’s pressure exceeds the strength of the crust, gigantic amounts of lava and ash are released in a catastrophic episode of eruption.

Caldera-forming eruptions are the most explosive volcanic eruptions on Earth and they often have had global effects. The ash and gas they put into the atmosphere can affect Earth’s climate and trigger social upheaval. For example, the eruption of nearby Okmok volcano in the year BCE 43 has been recently implicated in the disruption of the Roman Republic. The proposed caldera underlying the Islands of the Four Mountains would be even larger than Okmok. If confirmed, it would become the first in the Aleutians that is hidden underwater, said Diana Roman of the Carnegie Institution for Science in Washington, D.C., co-author of the study.

- Advertisement -

“We’ve been scraping under the couch cushions for data,” said Roman, referring to the difficulty of studying such a remote place. “But everything we look at lines up with a caldera in this region.”

Despite all these signs, Roman along with John Power, a researcher with the U.S. Geological Survey at the Alaska Volcano Observatory and the study’s lead author, maintain that the existence of the caldera is not by any means proven. To do that the study team will need to return to the islands and gather more direct evidence to fully test their hypothesis.

“Our hope is to return to the Islands of Four Mountains and look more closely at the seafloor, study the volcanic rocks in greater detail, collect more seismic and gravity data, and sample many more of the geothermal areas,” Roman said.

The caldera hypothesis might also help explain the frequent explosive activity seen at Mount Cleveland, Roman said. Mount Cleveland is arguably the most active volcano in North America for at least the last 20 years. It has produced ash clouds as high as 15,000 and 30,000 feet above sea level. These eruptions pose hazards to aircraft traveling the busy air routes between North America and Asia.

“It does potentially help us understand what makes Cleveland so active,” said Power, who will present the work. “It can also help us understand what type of eruptions to expect in the future and better prepare for their hazards.”

AMERICAN GEOPHYSICAL UNION

Header Image – The bathymetry for the Islands of Four Mountains area, based on depth soundings collected in the mid-20th century. Image Credit: Hélène Le Mével

- Advertisement -
spot_img
Mark Milligan
Mark Milligan
Mark Milligan is multi-award-winning journalist and the Managing Editor at HeritageDaily. His background is in archaeology and computer science, having written over 7,500 articles across several online publications. Mark is a member of the Association of British Science Writers (ABSW), the World Federation of Science Journalists, and in 2023 was the recipient of the British Citizen Award for Education, the BCA Medal of Honour, and the UK Prime Minister's Points of Light Award.
spot_img

Mobile Application

spot_img

Related Articles

Archaeologists find missing head of Deva from the Victory Gate of Angkor Thom

Archaeologists from Cambodia’s national heritage authority (APSARA) have discovered the long-lost missing head of a Deva statue from the Victory Gate of Angkor Thom.

Archaeologists search crash site of WWII B-17 for lost pilot

Archaeologists from Cotswold Archaeology are excavating the crash site of a WWII B-17 Flying Fortress in an English woodland.

Roman Era tomb found guarded by carved bull heads

Archaeologists excavating at the ancient Tharsa necropolis have uncovered a Roman Era tomb guarded by two carved bull heads.

Revolutionary war barracks discovered at Colonial Williamsburg

Archaeologists excavating at Colonial Williamsburg have discovered a barracks for soldiers of the Continental Army during the American War of Independence.

Pleistocene hunter-gatherers settled in Cyprus thousands of years earlier than previously thought

Archaeologists have found that Pleistocene hunter-gatherers settled in Cyprus thousands of years earlier than previously thought.

Groundbreaking study reveals new insights into chosen locations of pyramids’ sites

A groundbreaking study, published in the journal Communications Earth & Environment, has revealed why the largest concentration of pyramids in Egypt were built along a narrow desert strip.

Soldiers’ graffiti depicting hangings found on door at Dover Castle

Conservation of a Georgian door at Dover Castle has revealed etchings depicting hangings and graffiti from time of French Revolution.

Archaeologists find Roman villa with ornate indoor plunge pool

Archaeologists from the National Institute of Cultural Heritage have uncovered a Roman villa with an indoor plunge pool during excavations at the port city of Durrës, Albania.