A new report says that Alaska had a quieter year for earthquakes in 2022

[ad_1]

Effects of the 2018 earthquake near Wasilla. Earthquakes had a quieter year in 2022 (Image courtesy of the USGS)

Alaska (Alaska Beacon) – A new report from the Alaska Earthquake Center shows a quiet year for earthquakes in 2022. Last year alone, there were more than 47,000 earthquakes in Alaska and surrounding areas. Although this number is large, it actually represents a slight decrease in seismic activity compared to recent years, when activity was high.

“2022 has been a somewhat quiet year for us,” said Natalia Rupert, a seismologist with the Alaska Earthquake Center at the University of Alaska Fairbanks’ Institute of Geophysics. “But that’s how the earthquake cycle works.”

She said there are years of higher activity, like 2018, which was notable for a large earthquake near Anchorage, and years of lower activity. But she said the past five years have seen an exponential rise in recorded seismic activity.

There are two reasons for this, according to Robert. The first is a higher number of seismic stations in Alaska than in previous years.

During 2019 and 2020, a program funded by the National Science Foundation installed about 200 seismic sites in Alaska and western Canada for the purpose of tracking earthquake activity. As a result, more data is being tracked, and researchers are seeing a broader range of seismic activity in the state. The sites were scheduled to be removed by 2021, but the Alaska Seismic Center was able to acquire most of these sites to continue its research.

The second reason for the increase in seismic activity is aftershocks. Alaska has had a few large earthquakes in the past five years including the 2021 earthquake of magnitude 8.2.

Larger-magnitude earthquakes generate more aftershocks, Robert said, which can continue for years after the initial quake.

“We always underestimate the duration of aftershock sequences. The Anchorage earthquake was expected to have an aftershock sequence in the range of two and a half to three years, and now we are in that sequence four years or more.

Because of the unpredictable nature of earthquakes – even in quiet years like last year – Robert still stresses the need for public attention to earthquake activity.

“People have to stay prepared because in Alaska we have very high seismic rates, high seismic hazards, and it’s good for people to be prepared for a big earthquake at any time,” she said.

[ad_2]