When a Couple of Plates Move …

January 26, 2018

On Monday morning, people on the West Coast of the United States and Canada woke up to a rather startling surprise. An earthquake in the Gulf of Alaska kicked off fears of a possible … wait for it … tsunami!

If you were awake during the odd hours of Sunday night and were tracking the news, you might have heard about the earthquake first. A 7.9-magnitude earthquake struck shortly after midnight on Sunday, January 21st, near the southern part of Kodiak, Alaska. More than sixty aftershock quakes followed, and although they weren’t quite as big, there was enough concern for forecasters to send out warnings of possible tsunami waves.

Minor tsunamis did in fact occur in Alaska, and authorities issued tsunami warnings for the coastal regions of the United States and Canada. So were there actually any tsunamis? Well, no. The tsunami warnings were canceled after additional information clarified that there was no real threat.

Yes, we know you might have questions. Like … how did an earthquake that big not cause any damage? A magnitude of 7.9 is rather huge! After all, the 1906 San Francisco earthquake had a magnitude of 7.8, and it caused massive damage.

Image of San Francisco Earthquake destruction, 1906. Public Domain, https://commons.wikimedia.org/w/index.php?curid=1885949

Well, the recent earthquake near Alaska wasn’t as impactful because of the way tectonic plates move. When two tectonic plates move horizontally instead of vertically, the impact can be significantly less. Plus, the epicenter of the earthquake was underwater, resulting in less damage on land.

Has the United States ever really experienced a tsunami before? Actually, the West Coast has experienced tsunamis from quakes in Alaska before! Yep, that’s a piece of trivia many did not know. The most significant tsunami occurred in 1964, causing millions of dollars in damage near Crescent City in California.

Phew! But here is a question for you: Do people in California have Tsunami and Earthquake preparedness kits? That’s a good question for your local fire department. Report back! we’d love to know what they say! Email us at editor@xyzanews.com with what you learned.