Oregon Coast must prepare for repeat of the Great Cascadia Earthquake of 1700
Saturday, March 19, 2011
Through modern science one learns the Pacific Ring of Fire is ancient and constantly in motion, that devastating earthquakes and tsunamis within the “Ring” are cyclical events rather than singular ones. The fault lines in California and the Cascadia Subduction Zone in the Pacific Northwest are due for natural adjustments.
Scientists and historians believe the last major shift in the Earth’s tectonic plates in the Cascadia Subduction Zone occurred in 1700. Last week’s 9.0-magnitude earthquake and resulting tsunami in Japan have forced citizens and local governments along the West Coast to re-evaluate their contingency plans. The following resources help paint a picture of Oregon’s preparedness, or lack thereof.
• Ruth Zschomler, The Columbian: Cascadia Subduction Zone: Are Portland and Seattle prepared for an earthquake and tsunami?
About 50 miles offshore under the Pacific Ocean runs the Cascadia Subduction Zone, reaching from Northern California to British Columbia — more than 600 miles long. Unlike the San Andreas Fault where two tectonic plates butt up against each other, in a subduction zone one plate is pushed under the other. In Cascadia, the Juan de Fuca Plate is being shoved under the North American Plate.