How long was the Anchorage earthquake 2018?

That Anchorage Earthquake in 2018: When Alaska Shook for a Minute

Do you remember where you were on November 30, 2018? At 8:29 a.m. that day, Anchorage, Alaska, got a rude awakening. A magnitude 7.1 earthquake ripped through the area, and while the worst of the shaking was over in less than a minute, things weren’t quite the same afterward.

The Main Jolt and the Aftershocks That Just Kept Coming

The quake’s epicenter? About 8 miles north of Anchorage, near Point Mackenzie. It was pretty deep, too, around 29 miles down. And just when you thought it was over, BAM! Six minutes later, a 5.7 magnitude aftershock hit, practically on Anchorage’s doorstep.

Honestly, it felt like the aftershocks would never stop. By December 3rd, they’d already counted 170 aftershocks over magnitude 3.0. The scientists figured we’d be feeling them for almost a year. And get this – by the following November, they’d recorded something like 10,500 aftershocks!

Tectonic Plates Doing Their Thing

So, what caused all this shaking and rattling? Well, Southern Alaska sits right on top of the Aleutian Trench, where the Pacific plate is constantly diving under the North American plate. Think of it like a never-ending slow-motion collision. This particular quake was caused by a fault within the Pacific plate itself. It wasn’t a border dispute between the two plates, but more like an internal rumble. And just to give you an idea of how much these plates are moving, they’re converging near Anchorage at a rate of about 57 mm each year.

Damage, Injuries, and a Whole Lot of Shaken Nerves

The earthquake definitely left its mark. Buildings were damaged, and infrastructure took a beating. I remember seeing pictures of that highway overpass near the airport – it was a mess. Luckily, nobody died because of the earthquake itself, which is amazing. Still, over a hundred people were hurt, mostly with bumps, bruises, and frayed nerves. Some folks broke bones, and one poor guy even got smoke inhalation trying to put out a fire at his place after the quake.

When the Ground Gives Way

And it wasn’t just the shaking. The earthquake also caused the ground to turn to jelly in some places – what they call liquefaction – and triggered landslides. Those ground failures made the damage even worse. There were debris avalanches along the Eklutna River and slumping along the Alaska Railroad up near Mirror Lake. Nature showing off its power, for sure.

Just Another Day in Earthquake Country

Of course, earthquakes are just a fact of life in Alaska. We’re used to the ground moving. Alaska has a long history of big ones, including the monster 9.2 earthquake back in 1964. That one’s still the biggest earthquake ever recorded in the US, and the second biggest in the world. So, yeah, we know a thing or two about living with earthquakes up here.