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Though volcanic activity causes only a small proportion of Alaska's earthquakes, these earthquakes often warrant more detailed analysis. Ten-hour seismograms from a seismic station on Atka Island on August 6 & 7, 2008. The sudden appearance of numerous earthquakes was an early sign of an eruption that began later in the day on August 7. Not all swarms of earthquakes indicate eruptions; but nearly all eruptions are preceded by vigorous seismic activity. The Alaska Earthquake Center exists to minimize our risks by understanding where earthquakes occur and why. Tracking the earthquakes that occur each day provides clues about the earthquakes that are likely in the future.
Liquefaction models suggest potential impacts in localized areas throughout Anchorage and in the Matanuska valley. Liquefaction hazard is also high in low-lying areas of wet sediments elsewhere, though the human population is sparse. Still, ground failure in these areas could cause infrastructure impacts.
Anchorage earthquake left crumbling buildings, collapsed roofs and damaged roads
The Palmer exit at the Glenn/Parks interchange is now OPEN to one lane of traffic. We still advise you to avoid the area if possible and only travel if it is absolutely necessary. Every time a new bridge is constructed or an old one is worked on, the bridge is inspected by highly trained engineers, including experts in seismic design. In extreme cases, bridge inspectors can close a bridge to ensure your safety. Every single one of our bridges is inspected by bridge engineers at least every two years. They identify problems, if there are any, and repairs are prioritized and scheduled.
She told CNN that students were evacuated after the first main aftershock. ANCHORAGE — Tomasz Sulczynski had been driving for nearly four hours through rural Alaska on Friday when the biggest earthquake to hit the state in half a century began twisting the road beneath him. The airport terminal buildings sustained minor damage to light fixtures, water pipes, and windows. The DOT&PF Division of Facilities Services is conducting building assessments of state-owned buildings in the areas affected by the earthquake. Facilities staff will be working through the night and the weekend to assess damage and prepare for recovery. All DOT&PF Bridge inspectors are now in Southcentral Alaska and are conducting technical bridge inspections this morning.
Damage
On Facebook, longtime resident Mike Lewis said it was the strongest quake he’s ever felt, too. Lewis posted a picture of his kitchen, strewn with items and debris after the earthquake. Dimond High School senior Anna Krsnak was in second period when the earthquake hit.
Similarly, in Seward, students from other schools were evacuated to Seward High School. Watchstanders, or scientists who monitor earthquakes, get computer generated alarms indicating potential danger from quakes, but last Friday they didn’t need that. At the time of the tremblor, however, Spencer said they were in a café across the street. He said power went out almost immediately after the earthquake began.
Tsunami Hazard Map Tool
There will likely be vigorous aftershocks in the magnitude 4-5 range over the weeks and months following the January 23, 2018 earthquake, with aftershocks in the M6 range also possible, but less frequent. There is a small, but non-zero chance of the M 7.9 January 23, 2018 earthquake triggering a nearby event of comparable size or larger. Large quakes can cause well-water levels in areas far away from the quake to either drop or rise, depending on the local geology near the well, but not all wells show this effect.
DOT&PF and DOA continue to work together to ensure all workplaces are safe for employees and the public to return and are working to limit traffic on the Glenn Highway. Please report property damage to your department Administrative Service Director directly. ASDs are creating comprehensive lists of damage to be forwarded on to SSOA and Risk Management. We have some additional work in the SB today, but will open up to three lanes as soon as we can. Employees are expected to verify if their regular work site has been inspected and cleared. Please note that the following lists are being actively updated.
To request permits, or for any MSCVE relation inquiries, please email The map below shows the locations of damage to DOT&PF highways . Some of these damaged locations have already been repaired and some are scheduled to be repaired in the future. All bridges have been inspected by DOT&PF engineers and have been determined safe for travel. The Alaska Earthquake Center at the University of Alaska Fairbanks is a regional seismic network that participates in the USGS Advanced National Seismic System. AEC contributes seismic monitoring data and conducts analyses that are used in characterizing the 2018 Anchorage earthquake and its aftershocks.
We will minimize haul times by using the closest available asphalt plant as much as possible. We can add chemicals to the asphalt that will allow it to be compacted at lower temperatures than usual, which will give us more time to compact. Weather predictions are not favorable so please take extra precautions when traveling the roadways. Many times, in an emergency, we need to reach you during off-hours.
The Earthquake Center detects an earthquake every fifteen minutes, on average. In 2018, we reported an all-time high of over 54,000 earthquakes in Alaska. As our monitoring network improves, we report more earthquakes because we are able to detect smaller earthquakes across more of the state.
We are updating the earthquake website with the latest information. All DOT&PF Bridge inspectors are now in Southcentral Alaska and are conducting technical bridge inspections. Two inspection teams are covering the Glenn and Parks Highways, a third team is covering the Anchorage urban area, and a fourth inspection team is inspecting the bases of high mast towers. We are conducting inspections for all bridges in the earthquake affected area—250 bridge inspections—including state and local bridges. MSCVE offices are still closed due to earthquake damage in their building. Staff is working from remote locations and permits can still be issued.
This is a different mechanism than megathrust faults in the region, which do occur on the plate boundary itself. This faulting in the Pacific Plate is caused by downward bending while the plate is being forced under Alaska. Southern Alaska lies at the eastern end of the Aleutian Trench, where the Pacific Plate is subducting beneath the North American Plate. Near Anchorage, the plates are converging at a rate of 57 mm per year. The region has experienced severe earthquakes in the past, including several megathrust earthquakes. The 1964 earthquake, with a magnitude of 9.2, was the largest earthquake in American history and the second largest to ever be recorded anywhere in the world.
Subduction zone quakes have the potential to generate very strong ground shaking, and accompanying dangerous tsunamis as occurred in 1964. The western Aleutians, stretching from the western end of the Rat Islands in the east to the Commander Islands, Russia, in the west, is tectonically different from the central and eastern portions of the arc. Additionally, this portion of the subduction zone has not hosted large earthquakes or megathrust events in recorded history. Instead, the largest earthquakes in this region are generally shallow, predominantly strike-slip events with magnitudes between M5-6. Any strong earthquake shaking could potentially dislodge submarine landslides and trigger a deadly local tsunami. The next megathrust earthquake occurred along the central portion of the Aleutian arc near the Andreanof Islands on March 9, 1957, with a magnitude of M8.6.
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