From The University of Alaska-Fairbanks
1.25.24 [Just today in social media.]
Ned Rozell
907-474-7468
ned.rozell@alaska.edu
A volcanic crater containing a pond lies on a mountainside northeast of Healy, Alaska. The crater is part of the Buzzard Creek maars. Photo by Chris Nye.
Magma may have been discovered in a volcano-ness region known as the Denali volcanic gap. (Image credit: Carlos Rojas/Getty Images)
The team deployed seismometers around the Denali fault after an earthquake in the region, and accidentally found what appears to be a magma reservoir. (Image credit: Carl Tape)
For years, scientists have wondered why North America’s highest mountain is not a volcano. All the ingredients for volcanic activity lurk deep beneath Denali, which sits above where one planetary plate grinds past another.
Recently, while looking for something else, researchers found a reservoir of what might be magma, 7 miles beneath the muskeg of middle Alaska.
The spot intrigues Carl Tape because above it, at the ground surface, are ancient volcanic features.
Tape is a seismologist with the University of Alaska Fairbanks Geophysical Institute. A few years ago, he headed a team that peppered seismic instruments along the Parks Highway and on the Denali seismic fault. They installed hundreds of seismometers at spots along the road and dozens more right on the fault.
While looking at the seismometer data, which revealed ground motions large and small, Tape and his colleagues noticed a spot where earthen waves slowed down as they passed through.
“Sometimes a slowdown is due to sediments, such as those in the Tanana (River) valley,” he said. “Sometimes it’s due to magma. This one is beneath the Buzzard Creek maars.”
From left, Cole Richards, Lynn Kaluzienski and Carl Tape prepare to stick seismometers in frozen ground during a February 2019 mission to deploy instruments along the Denali seismic fault. The instruments helped scientists recently find the presence of a body of molten rock 7 miles deep. Photo by Ned Rozell.
The Buzzard Creek maars are two vegetated craters northeast of Healy. They formed when molten rock rose to the water table and blew up about 3,000 years ago. Geologists have found rocks around Buzzard Creek with the same chemical signature as Aleutian volcanoes.
Those volcanic features near Healy are within a region scientists have named the “Denali Volcanic Gap.” The gap is a puzzling absence of volcanoes from Mount Spurr (across Cook Inlet from Anchorage) to the Wrangell Mountains in eastern Alaska.
Volcanic activity of the Aleutian Islands seems to end at Mount Spurr, but if the curve of the Aleutian Arc were to extend north it would intersect the Alaska Range.
Other conditions there are favorable for volcanoes, too: Most of the Aleutians are located about 60 miles above where the slab of the Pacific plate plunges beneath the North American plate. The Buzzard Creek craters and the mountains of the Alaska Range (including Denali) are located about 60 miles above the interface of the giant plates.
University of Utah student Santiago Rabade pored over subtle signals picked up by the dense network of temporary seismometers Tape and his team had set up quickly in February 2019. Then, they performed rare winter fieldwork to detect aftershocks from a 7.0 Anchorage earthquake on Nov. 30, 2018.
A star marks the location of the Buzzard Creek maars. Illustration by UAF Geophysical Institute.
The earthen hum generated by ocean waves disturbing the sea floor is a constant source of noise we can’t feel but seismometers can; that signal allowed the scientists to detect the patch of magma beneath the Buzzard Creek craters.
“We had zero plan to look for what we found,” Tape said. “It’s fun to find results when you don’t seek them. And it’s generally better science.”
A next logical step to discover more about the mystery magma spot would be to cluster seismic instruments directly above it. Tape is hoping his team’s recent paper [Journal of Geophysical Research: Solid Earth] will inspire someone to take a closer look at the red blob that might help solve the riddle of the Denali Volcanic Gap.
See the full article here.
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The University of Alaska-Fairbanks is a public land-grant research university in College, Alaska; a suburb of Fairbanks. It is a flagship campus of the University of Alaska system. UAF was established in 1917 and opened for classes in 1922. Originally named the Alaska Agricultural College and School of Mines, it became the University of Alaska in 1935. Fairbanks-based programs became the University of Alaska-Fairbanks in 1975.
The University of Alaska-Fairbanks is classified among “R2: Doctoral Universities – High research activity”. It is home to several major research units, including the Agricultural and Forestry Experiment Station; the Geophysical Institute, which operates the Poker Flat Research Range and several other scientific centers; the Alaska Center for Energy and Power; the International Arctic Research Center; the Institute of Arctic Biology; the Institute of Marine Science; and the Institute of Northern Engineering. Located just 200 miles (320 km) south of the Arctic Circle, the Fairbanks campus’ unique location favors Arctic and northern research. UAF’s research specialties are renowned worldwide, most notably Arctic biology, Arctic engineering, geophysics, supercomputing, Ethnobotany and Alaska Native studies. The University of Alaska Museum of the North is also on the Fairbanks campus.
In addition to the Fairbanks campus, The University of Alaska-Fairbanks encompasses six rural and urban campuses: Bristol Bay Campus in Dillingham; Chukchi Campus in Kotzebue; the Fairbanks-based Interior Alaska Campus, which serves the state’s rural Interior; Kuskokwim Campus in Bethel; Northwest Campus in Nome; and the UAF Community and Technical College, with headquarters in downtown Fairbanks. UAF is also the home of UAF eCampus, which offers fully online programs.
The University of Alaska-Fairbanks enrolls over 9,000 students. Of those students, 58% were female and 41% were male; 87.8% were undergraduates, and 12.2% were graduate students.
Research units
The University of Alaska-Fairbanks is Alaska’s primary research university, conducting more than 90% of University of Alaska system research. Research activities are organized into several institutes and centers:
The Geophysical Institute, established in 1946 by an act of Congress, specializes in seismology, volcanology and aeronomy, among other fields.
The International Arctic Research Center researches the circumpolar North and the causes and effects of climate change.
The Institute of Northern Engineering, an arm of the College of Engineering and Mines, conducts research in many different areas of engineering.
The Research Computing Systems unit, located within the Geophysical Institute, is the high-performance computing unit of UAF.
The Alaska Agricultural and Forestry Experiment Station conducts research focused on solving problems related to agriculture and forest sciences.
The Institute of Arctic Biology conducts research focused on high-latitude biological systems.
The Robert G. White Large Animal Research Station conducts long-term research with muskoxen, reindeer and cattle.
The Institute of Marine Science, a branch of the College of Fisheries and Ocean Sciences, investigates topics in oceanography, marine biology, and fisheries.
The R/V Sikuliaq, a 261-foot ice-resistant ship outfitted with modern scientific equipment, is operated by the College of Fisheries and Ocean Sciences for the National Science Foundation.
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