Tag Archives: earthquake

The Good Friday Earthquake

64 Quake Map

It was 50 years ago today, at 5:36pm AST, when the megathrust earthquake hit southern Alaska. The ground shook for over 4 minutes, causing tsunamis that wiped out coastal villages before the shaking stopped. The magnitude 9.2 quake remains the largest to be recorded in North America. In the five decades since, no earthquake has matched the power of the 1964 Good Friday Earthquake.

Kodiak, AK after Good Friday Quake
Kodiak after the 1964 Alaska Quake. Note the green Willys Wagon!

139 lives were lost (tsunami 124, earthquake 15), which, considering the magnitude of the quake, is amazingly low. The maximum tsunami wave height recorded was 67 meters (220 feet) at Shoup Bay in the Valdez Inlet. The community of Valdez was wiped out. Kodiak, Seward, Portage, Anchorage, Chitina, Glenallen, Hope, Homer, Moose Pass, among others, all saw severe damage.

4th Ave Anchorage B&W
4Th Avenue, Anchorage after the ’64 Quake

In the day following the earthquake, there were 11 major aftershocks that reached a magnitude of 6.2 or higher. There were thousands of aftershocks in the three weeks after the main shock, and it was a year later when the aftershocks were no longer noticed.

Seward Hwy 64 Quake
The Seward Highway, March 28, 1964

Color graphic courtesy of Live Science, photos courtesy of the University of Alaska Archives.


Denali Fault Quake

Ten years ago yesterday, the 7.9 magnitude Denali Fault Quake hit Interior Alaska. It remains the largest earthquake I have experienced. I was stopped at a light on University Avenue in my ’66 Chevy pickup, when the truck suddenly started to lurch & sway. It was actually hard to stay on the brakes, so I popped the transmission into neutral. Two guys in a car next to me rolled down a window and asked me, “What the hell is going on?” All I said was, “Earthquake.” The passenger in the car then smacked his buddy on the head and said, “I told you it was an earthquake!”

The shaking went on for a surprisingly long time. I remember an elderly couple had been walking down the sidewalk, the woman couldn’t keep her balance and she dropped to the concrete. Her husband stayed upright only by holding onto a street sign. When he offered her his hand to help her up, she only shook her head. It was probably a good idea to wait until the Earth stopped shaking.

A friend of mine was walking his dogs across the frozen tundra when it hit. He watched a “wave” move across the ice on the frozen pond in front of him. He was forced to hold onto a spruce tree to keep from falling to the ground.

In October of 2002, we had experienced a foreshock, in the form of a 6.7 quake. At the time, the experts were on the radio telling us that the Denali Fault could produce an 8.0. but doubted that it could produce anything larger. I couldn’t help but wonder how the hell they could conclude that, but a month later we found ourselves on the 8.0 doorstep. It was the largest quake ever recorded in Interior Alaska, and the largest in the interior of the United States in over 150 years.

Both the Parks & Richardson Hwys suffered damage, and the Tok Cutoff suffered a 23 foot offset. The Alaska Pipeline did exactly what it was suppose to do where it crosses the fault: It slid laterally on the beams it sits on and no oil was spilled. A peak out at Black Rapids showed the most dramatic change with a rather large landslide.

In Seattle, the Supersonics were in pregame warmups, when the main scoreboard started to sway, due to our trembler.

3 November 2002


48 Years Ago

On 27 March 1964 at 5:36pm a 9.2 magnitude earthquake hit Prince William Sound. 115 Alaskans were killed from the quake and the tsunamis that followed. 16 people also died in Oregon and California.

The Good Friday Earthquake was a megathrust quake that shook Alaska for over 4 minutes straight. It released 50 times as much energy as the 1906 San Francisco earthquake; fishing boats in Lousiana sank, well water in South Africa rose, Sheep Creek in Anchorage stopped flowing for 18 hours, and the intervals of eruptions of Old Faithful Geyser in Yellowstone shortened. It is the largest earthquake to hit North America and the second largest to ever be recorded. There were thousands of aftershocks in the weeks following. The next day alone had 11 shocks registering over 6.0.

100,000 square miles of Alaska twisted, broke, dropped and rose. The coastal community of Portage dropped ten feet causing flooding from Turnagain Arm. The town of Seward moved 47 feet south, Cordova 46 feet southeast, and parts of Montague Island rose 30 feet.

The tsunamis caused the most damage and loss of life. The waves that hit Shoup Bay reached 100 feet above sea level, and 60 feet above sea level at Kodiak. Some remote areas show evidence of waves 220 feet above sea level.