Cluster of six Alaskan volcanic islands may be an interconnected giant volcano that is similar to the Yellowstone Caldera with previous eruptions more powerful than Mount St. Helen in 1980, study reveals
- The Islands of the Four Mountains in Alaska is made of six volcanic islands
- Experts now suggest they interconnect to make a single, giant volcano
- The team believes the giant volcano is similar to the Yellowstone Caldera
- They mapped the seafloor and saw several curved structures on the seafloor
- A depression more than 400 feet deep was seen that may be part of the caldera
A small cluster of volcanic islands in Alaska may be part of a single giant volcano similar to that of the Yellowstone Caldera and others that have had super-eruptions in the past.
The group belongs to the Islands of the Four Mountains in the central Aleutians, which consists of six stratovolcanoes named Carlisle, Cleveland, Herbert, Kagamil, Tana and Uliaga.
However, a team from the American Geophysical Union suggests they form one interconnected caldera that could have produced an eruption more powerful than the 1980 Mount St. Helens.
The hypothesis, according to the researchers, might also help explain the frequent explosive activity seen at Mount Cleveland over the past 20 years that has released ash clouds as high as 30,000 feet above sea level.
A small cluster of volcanic islands in Alaska may be part of a single giant volcano similar to that of the Yellowstone Caldera and others that have had super-eruptions in the past
Although this undiscovered volcano could be massive, the team notes it does not suggest a catastrophic event is in the near future.
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 group belongs to the Islands of the Four Mountains in the central Aleutians, which consists of six stratovolcanoes named Carlisle, Cleveland, Herbert, Kagamil, Tana and Uliaga
An image of the seafloor shows several curved structures and a depression more than 400 feet deep that could be part of the caldera
The proposed caldera underlying the Islands of the Four Mountains would be even larger than Okmok.
Diana Roman of the Carnegie Institution for Science in Washington, D.C., co-author of the study, said: ‘We’ve been scraping under the couch cushions for data.’
‘But everything we look at lines up with a caldera in this region.’
Roman and her team have collected a range of evidence, including gravity anomalies from satellite data and bathymetric surveys that were conducted in the area shortly after World War II, National Geographic reports.
Although the images were low resolution, the team was able to see several curved structures on the seafloor and a depression more than 400 feet deep that could be part of the caldera.
If their suspicions are confirmed, the team believes that the potential underwater basin may have resulted from a volcanic explosion that was just shy of earning the label ‘super eruption.’
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.
The hypothesis, according to the researchers, might also help explain the frequent explosive activity seen at Mount Cleveland (pictured) over the past 20 years that has released ash clouds as high as 30,000 feet above sea level
These eruptions pose hazards to aircraft traveling the busy air routes between North America and Asia.
John Power, a researcher with the U.S. Geological Survey at the Alaska Volcano Observatory, said: ‘It does potentially help us understand what makes Cleveland so active.’
‘It can also help us understand what type of eruptions to expect in the future and better prepare for their hazards.’
The team is set to present their findings at the American Geophysical Union’s Fall Meeting 2020 on December 7, 2020.