Researchers monitoring the most perilous fault lines in the United States are issuing a new alert — a massive tsunami event in the Pacific is no longer a matter of if, but rather when it will occur. The Cascadia Subduction Zone, located off the coasts of Oregon, Washington, and northern California, has experienced over 320 years without a significant rupture, with magnitude 9 earthquakes happening every 250 to 500 years. When it finally occurs, waves exceeding 100 feet could reach US coastal communities in just 20 minutes. The hazards are compounded by Alaska's Barry Arm fjord and Hawaii's exposure to the Pacific. Here’s what every coastal resident in America should be aware of.
