In 1700, a magnitude 9 earthquake dropped the Pacific Northwest coast by several feet in a single night, and the fault that did it is locked and loading again right now.

The Cascadia Subduction Zone runs 700 miles from Northern California to Vancouver Island, under Seattle, Portland and dozens of coastal towns. We follow the scientific detective story that proved it: ghost forests, buried sand layers, Indigenous oral histories and Japan's mysterious orphan tsunami.
Then we explain how a locked subduction zone works, why it's far more dangerous than the San Andreas Fault, and what FEMA's models say a full rupture and a 50-foot tsunami would do today.
Finally, the honest odds: how likely the next big Cascadia earthquake is in our lifetime, and what ShakeAlert, evacuation towers and drills can and can't do.

Subscribe if you want to actually understand the ground you're standing on, and tell us in the comments which disaster we should break down next.

Chapters:
0:00 A Wave From Nowhere
1:02 Where Is Cascadia?
3:00 The Buried Sand
4:53 The Orphan Tsunami
7:28 That Night
11:20 How It Works
15:18 If It Hit Today
18:01 Getting Ready
19:39 Will It Happen?

#earthquake #cascadia #tsunami

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