Quietly Active: Earthquakes in Oregon 1700-2016

Did you know that here in Oregon there were more than 14,000 known earthquakes from 1841 to 2002? Or that Geological evidence shows large subduction zone earthquakes struck Oregon’s coast every 300-800 years, back as long as 11,000 years? Far more common are smaller, but sometimes damaging, quakes that rock Portland and the Willamette Valley, the Klamath Falls area, northeastern Oregon and the coast.

Image source: U.S. National Archives and Records Administration

Image source: U.S. National Archives and Records Administration

November 2016 – Central Oregon Coast

Two earthquakes, measuring 4.9 and 4.8 were detected off the Oregon central coast near Bandon.

November 19, 2012 – Portland

Portland residents felt a minor earthquake with a 3.1 magnitude. No injuries or damage were reported.

March 25, 1993 – Willamette Valley

Salem, Molalla, Woodburn, Newberg, Mount Angel and other communities were rocked by a quake that caused more than $28,000,000 in damage. A bridge jumped off its supports. Parts of the facade of Molalla Union High School collapsed (with no injuries). In Mount Angel, the Benedictine convent, abbey, and St. Mary’s church and school were damaged. In Salem the quake caused $4,500,000 to the State Capitol alone.

1993 Quakes – Klamath Falls

In 1993 a swarm of earthquakes up to magnitude 6 hit the Klamath Falls area. On September 20, 1993, a man become the first fatality from an earthquake in Oregon when a boulder was rocked loose from a hillside and landed on his pickup. More than 1,000 buildings were damaged, causing $7.5 million in damage. Unreinforced masonry buildings got the worst damage, including the 1924 Klamath County Courthouse. Wood-frame houses bolted to foundations came through with little damage.

March 13, 1985

A Magnitude 6.1 quake strikes off the Oregon Coast, west of Coos Bay.

April 12, 1976 – Deschutes Valley

A magnitude 4.8 earthquake centered near Maupin in north-central Oregon, causing minor damage.

May 29, 1968 – Warner Valley

West of Steens Mountain, a series of earthquakes hit tiny Adel in the Warner Valley. The largest quake with a magnitude of 5.1 caused rockslides and damaged buildings. Highways formed cracks up to 1 inch wide.

November 5, 1962 – Portland

A magnitude 5.5 quake struck Portland, causing minor damage, including broken windows and collapsed chimneys.

December 16, 1953

A magnitude 5.6 quake hits Portland area and Vancouver. No damage.

July 16, 1936 – Northeastern Oregon

A quake as high as 6.1 magnitude hit northeastern Oregon in the Milton-Freewater area around midnight. It damaged chimneys, shifted houses  off their foundations, and caused landslides. Caused $100,000 in damage (1936 dollars).

March 7, 1893

An estimated magnitude 5.7 quake in Umatilla in northeast Oregon.

February 3, 1892

Building swayed and people strongly felt and earthquake over a large area, from Astoria to Salem.

October 12, 1877

An earthquake centered in the Cascades, magnitude 5.3, damaged chimneys in the Portland area.

November 23, 1873

An estimated 6.8 magnitude earthquake hit Crescent City, California and Brookings, Oregon, knocking down chimneys.

Jan. 26, 1700

The most recent major Cascadia quake, estimated magnitude 8.7 to magnitude 9.2, stretched from Vancouver Island to northern California. The quake was recalled by oral traditions of native peoples and is corroborated by sediment studies, tree ring studies, and written records of a tsunami in Japan.

Before 1700

Geologic evidence of periodic magnitude 8 or higher earthquakes.

What you can do

You can act before an earthquake strikes by preparing your home. Houses built before 1970 are at the greatest risk, often requiring retrofits even to become eligible for earthquake insurance. A mix of upgrades, tailored to your home, can greatly reduce financial and safety risks to your home and family. Enhabit Home Advisors offer complimentary phone consultations to discuss your options and investigate the next steps.

Schedule a Phone Consultation Now

Or reach us at (855) 870-0049 or [email protected]

 

Resources

2 earthquakes recorded off Oregon coast – Oregonlive.com

Living with Earthquakes in the Pacific Northwest – Oregon State University

Big Steps Before the Big One: How the Portland area can bounce back after a major earthquake – Portland City Club

History Of Earthquakes In Cascadia – Cascadia Region Earthquake Workgroup

Map of Selected Earthquakes for Oregon, 1841-2002 – Oregon Geology

A look back at Oregon’s earthquake history, 1841-1994 – Oregon Geology Volume 57 Number 6, November 1995