Near Sitka, Alaska, a dormant volcano is active again after 800 years of silence. When will this giant awaken from its slumber soon and does this mean an eruption is underway? An expert explains the likelihood of an eruption.
The Sleeping Giant Stirs
Since Mount Edgecumbe has been dormant for at least 800 years, scientists have discovered fresh evidence that the sleeping giant might be awakening as a result of a wave of earthquakes that has been rumbling through the region for the past months.
Mathematical modeling derived from satellite imagery was used in research by the Alaska Volcano Observatory and Alaska Satellite Facility to establish that the recent increase in seismic activity was brought on by the upward thrust of the moving magma that is deep beneath the earth's surface.
David Pyle, a volcanologist from the University of Oxford, explained in an interview with Newsweek that both of these processes, which occur when magma is moving and forcing its way along cracks or forming an expanding pool of molten rocks at depth, can result in minor earthquakes.
He added that much smaller than what a human would be able to perceive, earthquakes and tremors can be detected by seismometers. The signals from earthquakes can be used to identify the location where the earthquakes originate if several seismometers are positioned all around a volcano.
The earth above the magma expands like a balloon as it makes its way upward toward the surface.
Pyle said that the use of satellite radar instruments is a crucial component of volcano monitoring. They are capable of measuring even the smallest variations in the surface's shape.
From these radar measurements, it can be inferred that the surface bulges slightly when magma is shifting at a depth, within several kilometers of the Earth's crust. To determine the shape and structure of the magma body within the Earth in three dimensions, experts combine this information with earthquake locations.
Mount Edgecumbe
In comparison to other nations, the US has the most volcanoes, the majority of which are in Alaska. Only 42 of the country's 161 possibly active volcanoes have shown activity in the past 70 years, according to the US Geological Survey.
As per geological evidence, Mount Edgecumbe's most recent major eruption occurred about 4,500 years ago, even though it is believed to have had some volcanic activity 800 years ago. As a result, it has frequently been referred to as "dormant."
According to Pyle, the term "dormant" is commonly used to refer to volcanoes that have not yet erupted in decades or centuries and may appear to be completely silent. However, the implied message is that extinct volcanoes could erupt at any time.
He continued to say that the lifespan of the majority of volcanoes can reach hundreds of thousands of years. Once magma rises from the interior of the Earth and gets to the surface during this time, the volcano in question might erupt. Then, as the magma cools between eruptions, they might go back to dormancy. When more magma begins to rise beneath the volcano, it becomes restless once more and is said to be "re-activated."
Read also: Scientists Urge Humanity to Prepare for Colossal Dangers of Next Super Eruption
Next Eruption for Mount Edgecumbe
However, the recent increase in volcanic activity beneath Mount Edgecumbe may not necessarily imply a future eruption.
According to National Geographic, it is crucial for scientists to carefully monitor any volcanoes close to major population centers because volcanoes can give some warning signs of an impending eruption. Swelling or bulging of the volcano's sides, small earthquakes, and increased gas emissions from its vents are all warning signs. None of those indicators necessarily indicate that an eruption is about to occur, but they can aid researchers in assessing the volcano's condition when magma is forming.
Pyle said that although the presence of magma activity at depth frequently serves as a way to remind everyone that a volcano is active or potentially active, it does not always indicate that the volcano will erupt.
He continued to say that there have been numerous instances over the past 20 years during which scientists have used seismic activity and satellite imagery in tandem to observe new magma entering a volcano. And in the majority of these instances, there is no eruption; instead, the disturbance subsides after several weeks or months, Newsweek reports.
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