Tag Archives: Alaskas

Ancient Salmon and Pike Ancestors Thrived in Alaska’s Freshwater 73 Million Years Ago

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Paleontologists have identified three new fossil species. Sivulliusalmo Alaskensis was found in a purine cream formation in northern Alaska, USA.

Chinook salmon (oncorhynchus tschawytscha). Image credit: US Geological Survey.

“Sivulliusalmo Alaskensis reveals significant insights,” remarked Dr. Patrick Druckenmiller, the director of the University of Alaska Museum in the North.

“Our research uncovers several additional species of ancient fish new to the Arctic, including two new pike species: Archaeosiilik Gilmulli and Nunikuluk Gracilis, as well as the oldest record within the group comprising carp and minnows.”

“Many fish we now consider unique to Alaska’s high-latitude environment existed alongside dinosaurs.”

The discovery of Sivulliusalmo Alaskensis adds an impressive 20 million years to the fossil history of the salmon family.

Previously, the oldest known salmonidae fossil was from British Columbia and Washington.

“It’s noteworthy that the Salmonidae, which typically thrives in cold water, adapted and flourished during the warm Cretaceous period, enduring for millions of years amidst significant geographical and climatic changes,” noted Andres Lopez, Fish Curator at the University of Alaska in the north.

“Even though the Arctic was warm during that era, there would still be substantial seasonal variations in temperature and sunlight, much like today.”

“Salmon were among the fish adept at navigating these dramatic shifts.”

“Despite the planet’s numerous geological and climatic transformations, the ancestors of the same species group persisted in dominating the region’s freshwater ecosystems.”

The new species is the latest finding from the Prin Creek Formation, renowned for its dinosaur fossils discovered along the Colville River in northern Alaska.

During the Cretaceous period, Alaska was significantly closer to the Arctic than it is today.

“Fish fossils are among the most abundant in the Purine Creek Formation, yet they are challenging to distinguish in the field,” stated Dr. Druckenmiller.

“Consequently, we transported the fine sand and gravel samples to our museum lab, where microscopic analysis revealed the bones and teeth.”

“Our new findings heavily rely on small, fossilized jaws, some of which are small enough to fit on the edge of a pencil eraser.”

For detailed examination, the researchers employed micro-computed tomography to digitally reconstruct the small jaws, teeth, and other bones.

“We identified very distinct jaws and other components of the salmon family, which were recognized as belonging to this lineage,” said Dr. Druckenmiller.

“The presence of salmonidae in the Cretaceous polar regions and their coexistence with common low-light fish from this period suggests that salmonidae likely thrived in northern climates.”

“The high latitudes of the northern regions may have been vibrant centers for their evolutionary development.”

This paper was published in the journal Paleontology papers.

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Donald B. Brinkman et al. 2025. Fish from the Purine Cream Formation in the northern slopes of Alaska: the pre-Cretaceous and their paleobiogeographic significance. Paleontology papers 11(3): E70014; doi: 10.1002/spp2.70014

Source: www.sci.news

Scientists warn that volcanoes near Alaska’s largest city may erupt in the next few weeks or months

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Anchorage, Alaska – Volcanoes near Alaska’s biggest city show new signs of anxiety. Experts say the likelihood of an eruption in Mount Spall is increasing in the coming weeks or months.

The Alaska Volcanic Observatory said Wednesday it measured “a significant rise in volcanic gas emissions” during recent turbulence, with the signs indicating that the eruption was not certain in weeks or months, but not certain.

“We hope for more seismic activity, gas emissions and surface heating before the eruption. “Such strong anxiety could provide additional warnings for days to weeks.”

What is Mount Spur?

It is an ice-covered volcano about 80 miles northwest of Anchorage, 11,070 feet high.

Mount Spur is one of Alaska’s 53 volcanoes and has been active within the last 250 years. There are two main vents.

When did Mount Spur last erupt?

The last known eruption from the Summit Bent was over 5,000 years ago. Meanwhile, Crater Peak Vent erupted once in 1953 and three times in 1992. Crater Peak Vent is about two miles south of the summit.

Since then, there have been periods of increasing earthquakes and other activities between 2004 and 2006, but no other eruptions. Last October, the observatory raised the green to yellow mount spur alert status when seismic activity increased significantly and ground deformation was discovered in satellite data.

The most likely outcome of current anxiety would be the eruptions or eruptions of 1953 and 1992, the observation deck said.

But “there is a possibility that there will be no eruptions, current activity will die slowly, or even smaller eruptions may occur,” wrote John Power, a geophysicist at the station’s US Geological Survey, in an email.

What are the effects of the eruption?

According to the observation deck, eruptions of the last century lasted three to seven hours, rising more than 50,000 feet above sea level, producing ash columns deposited ashes in communities in southern Alaska.

In 1992, about a quarter inch of ash from the anchorage began to stay inside or wear masks if they were to go outside to avoid breathing the ashes. The clouds drifted all the way to Greenland.

Volcanic ash is angular and sharp, and is used as an industrial abrasive. Powdered rocks can shut down the jet engine.

The 1992 eruption prompted temporary closures of airports in Anchorage and other communities.

In states where most communities are not connected to Alaska’s main road system, closing airports is more than inconvenient. Ted Stevens Anchorage International Airport is one of the busiest cargo hubs in the world.

Source: www.nbcnews.com