Coastal M5.4 Earthquake Likely From Within the Subducting Slab
The M5.4 earthquake on Sunday morning March 19th was widely felt in Kenai Peninsula communities and as far as the MatSu valley (Fig. 1). With a depth of 40.6 miles, it is likely that this earthquake occurred in the Pacific Plate.
Have you ever wondered how seismic analysts locate earthquakes? Or maybe why earthquake solutions change over time? With the Alaska seismic monitoring network, we record an average of 100+ events daily.
What happens when background noise is louder than an earthquake?
Noise is all around us, all the time. Vibrations in the earth are much the same. Natural and anthropogenic (or man-made) vibrations are a constant source of noise that is recorded on seismic sensors around the world.
New multidisciplinary project will boost understanding of earthquakes and Arctic change in Alaska
A new collaborative project will make it possible for scientists to use real-time seismic, weather, and infrasound (sounds below levels that humans can hear) observations to track a suite of phenomena ranging from earthquakes to wildfires to sea i
This evening’s M7.8 earthquake [7/21/20, 10:12 PM AKDT] occurred on the well-known subduction zone interface off the Alaska Peninsula. Strong shaking has been reported from Perryville and Sand Point to King Cove and Cold Bay.
We use the phrase “magnitude of completeness” often when referring to our understanding of seismicity in a region or following a sequence of earthquakes. This value is a simplistic assessment of a catalog of earthquakes.
Unraveling current earthquakes in the western Aleutians
We are getting questions about current earthquake activity in the western Aleutians—and with good reason. There are actually two different sequences of earthquakes unfolding right now in the Andreanof and Rat Islands.
2019 Is Runner Up for the Highest Number of Earthquakes: Alaska Seismicity Summary
Seismicity in Alaska had another stand-out year in 2019. With a total of 50,289 reported earthquakes, 2019 finished as a runner up to the record-breaking 2018 (figure 1). The earthquake depths ranged between 0 and 165 miles (265 km).
Symposium on the Anchorage earthquake, September 24-26
Registration is open for this retrospective on the M7.1 earthquake last November. This is a diverse gathering of professionals who are vested and interested in helping shape the lessons learned from this event.
Our staff spend much of their time each summer working in the field on the stations that make up our seismic network, but the work of maintaining these stations is not limited to the summer or even to the field.
If you've paid much attention to earthquakes in Alaska over the last few years, you've probably heard the phrase “earthquake swarm.” In 2014, a swarm near Noatak rattled residents with five magnitude 5.3-5.7 earthquakes spread out over two months.
Why magnitudes evolve in the minutes after an earthquake
If you've ever read one of our old information releases, you might have noticed the phrase "The magnitude and location may change slightly as additional data are received and processed." The words probably make sense, but the reasons are a bit sub
The burning question on the minds of many residents in Southcentral Alaska is, “When will the aftershocks stop?” This is a tricky question, but enough time has passed since the November 30 magnitude 7.1 earthquake for us to make an informed estima
Phantom quakes: what they are and why they're getting scarcer
If you were one of the thousands of people visiting our website this morning or using one of the numerous services that repost our data (various phone apps, USGS, etc.) you may have seen listings for two magnitude 5 earthquakes at the same time ne
Knowing where to go with pedestrian tsunami evacuation modeling
Knowing where to go during an evacuation is crucial to survival when you are in a tsunami hazard zone. But how do emergency managers and planners decide where the safe zones are and where to stage assembly areas in a community?
M6.4 Kaktovik earthquake: the largest ever on the North Slope
On Sunday morning at 6:58 Alaska time, we recorded a magnitude 6.4 earthquake 52 miles southwest of Kaktovik. It was, by a wide margin, the largest earthquake ever recorded north of the Brooks Range in Alaska.
Not only do our remote seismic stations need to survive temperatures far below zero, heavy snows, ice, winds, rains, lightning strikes, and warm, muddy summer months, our stations must also withstand abuse from all variety
When is an earthquake about to happen? Foreshocks, Earthquake Nucleation, and Earthquake Prediction/Forecasting
For decades, there have been tantalizing clues about how we might know when an earthquake will happen. Sometimes, clusters of small earthquakes called foreshock sequences come in the days or weeks before a large earthquake.
Landslide tsunamis: why they're different and how to prepare
Alaska's most recent deadly tsunami struck without warning on November 3, 1994. Witnesses described new steel sheet piles snapping in half as the railway dock, which was being refurbished, suddenly slid away from the shore.
With a trip to Chirikof Island, field season is underway
Two of our field crew, blessed with adequate weather, made the 180-mile flight from Kodiak to Chirikof Island last week. Once there, they replaced two aging seismometers, measured battery voltages and radio signal strength, and then checked on the
Earthquakes beneath and around Denali are very common and in fact encapsulate three stories of Alaska seismicity in one location. Last night’s (Tuesday 31 January) magnitude 5.2 earthquake is just one part of the Denali regional story.
The almost forgotten earthquake of the Alaska Gold Rush
UAF's Carl Tape will be speaking on Tuesday night in Fairbanks about his research into an elusive 1904 magnitude 7.3 earthquake that happened, we now believe, somewhere near Lake Minchumina. This is a detective story.
Four hundred miles from the epicenter, at 1:30 in the morning, many in Fairbanks did not feel the earthquake at all. For those who did, it lasted for a long time and came as two distinct, widely separated shocks.
The recent nuclear test in North Korea presents a quandary for seismologists. The political posturing and global tension these events create is significant. And yet scientifically, they are fascinating.
As we head into winter, seismic events generated by glaciers—so-called icequakes—have quieted down for the season. Each year, hundreds of these icequakes are large enough to be caught by our standard earthquake detection routines.