Article

Cascadia’s Fault by Jerry Thompson: America’s Earthquake and Tsunami

Cascadia’s Fault by Jerry Thompson shows that America’s earthquake and tsunami may devastate the Pacific Northwest in the twenty-first century.

Cascadia is offshore from North America’s continental plate Cascadia’s Fault by Jerry Thompson acquaints readers with America’s earthquake and tsunami, which may devastate the Pacific Northwest sometime earlier or later in the twenty-first century. Moderate, strong, major, and great belong with the words that nobody likes to hear regarding earthquakes since they respectively describe magnitudes 6, 7, 8, and 9. Even a magnitude 6 can be disturbing, as in the case of the Parkfield area stretch of California’s San Andreas fault rupturing six times since 1857. But its devastation does not come anywhere near that of magnitudes 9.2 on March 27, 1964, in Alaska and 9.5 on May 22, 1960, in Chile. Some seismologists expect Cascadia to rupture catastrophically after three quiet centuries since 1700. ***** Website: http://www.cascadiasfault.com *****

The Cascadia Subduction Zone lies within the Pacific Ring of Fire. The Pacific Ring refers to volcanic arcs and oceanic trenches that partly encircle the Pacific. The Ring of Fire is a zone of frequent earthquakes and volcanic eruptions.

W. Jacquelyne Kious and Robert I. Tilling, "Understanding plate motions," This Dynamic Earth (February 1996) — US Geological Survey, Public Domain, via USGS Geomaps

Cascadia is offshore from North America’s continental plate

The Pacific Ring of Fire of earthquakes, eruptions, and tsunamis from New Zealand, through Asia, to the Americas furnishes 15 of the 16 mega-earthquakes since 1900.

The Ring generates cluster earthquakes, with the Pacific plate’s southeast, southwest, and northwest corners rupturing on February 27, 2010, February 22, 2011, and March 11, 2011. In the above-mentioned cases, the Peru-Chile Trench, the Izu Ogasawara, Japan, and Ryukyu Trenches, and the Kermadec Trench respectively huddle off Chile, New Zealand, and Japan. The trenches off these three countries and off Alaska, Indonesia, Mexico, New Guinea, Philippines, Siberia, and Tonga identify zones where sea plates move under land plates.

From the Pacific plate’s northeast corner, Cascadia’s subduction zone joins the trench warfare.

Cascadia earthquake sources: subduction zone, deep Juan de Fuca plate, crustal faults

Pacific Northwest geologic mapping and urban hazards — US Geological Survey, Public Domain, via USGS Geomaps

Cascadia juggles three sea plates and one trench

Cascadia’s fault line from Cape Mendocino in northern California, through Oregon and Washington, to Vancouver Island off British Columbia in western Canada keeps low geo-historical profiles.

Cascadia’s 19 full margin ruptures of magnitude 9 and 22 partial margin ruptures of magnitude 8 in 10,000 years lead seismologists to rethink California’s upcoming mega-quake. Cascadia’s northern end from mid-Oregon to mid-Vancouver Island and southern end from Cape Mendocino to Newport, Oregon, manifest respectively recurrent intervals of 480 and 240 years. Dr. Kenji Satake of the Geological Survey of Japan and co-authors Kunihiko Shimazaki, Yoshinobi Tsuji, and Kazue Ueda note January 26, 1700, for Cascadia’s last mega-earthquake.

They offer 21:00 local time based upon 10-hour tsunami travel times to Japan.

Cascadia earthquake sources: map of Juan de Fuca plate

Cascadia lets the Juan de Fuca Plate subduct

Japan proves to be among the world’s most earthquake- and tsunami-prone countries because of offshore trenches and proximity to the Marianas, Philippine, and Siberian (Kuril) Trenches.

Generations of earthquake and tsunami data-gatherers in Japan always question a natural disaster’s origins, particularly regarding orphan and phantom tsunamis independent of earthquakes in the archipelago. Entries from January 27 and 28, 1700, reveal 16-foot (4.88-meter) orphan tsunamis devastating 560-mile (901.23-kilometer) stretches from Kuwagasaki to Tsugaruishi, Kubota Crossing, Nakaminato, Miho, and Tanabe. Japan’s records serve to reinforce Huu-ay-aht, Makah, and Yurok oral histories from Pachena Bay and Columbia River, Copalis River, Grays Harbor, and Willapa Bay ghost-forest dendrochronology.

Cascadia’s Fault takes readers on culturally enriching, educationally entertaining, and geo-historically enthralling adventures.

"Tsunami Forecast Model Animation: Cascadia 1700" (1:20)

Uploaded January 26, 2015, by PacificTWC (Pacific Tsunami Warning Center) to YouTube ~ URL: https://www.youtube.com/watch?v=4W2iUl0VB8c

Tsunami Forecast Model Animation: Cascadia 1700

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image Credits

The Cascadia Subduction Zone lies within the Pacific Ring of Fire. The Pacific Ring refers to volcanic arcs and oceanic trenches that partly encircle the Pacific. The Ring of Fire is a zone of frequent earthquakes and volcanic eruptions.
Trenches are shown in blue-green. The volcanic island arcs, although not labelled, are parallel to, and always landward of, the trenches. Illustration by Jane B. Russell.
W. Jacquelyne Kious and Robert I. Tilling, "Understanding plate motions," This Dynamic Earth (February 1996): US Geological Survey, Public Domain, via USGS Geomaps @ https://pubs.usgs.gov/gip/dynamic/understanding.html

Cascadia earthquake sources: subduction zone, deep Juan de Fuca plate, crustal faults
Pacific Northwest geologic mapping and urban hazards: US Geological Survey, Public Domain, via USGS Geomaps @ http://geomaps.wr.usgs.gov/pacnw/pacnweq/index.html

Cascadia earthquake sources: map of Juan de Fuca plate
Pacific Northwest geologic mapping and urban hazards: US Geological Survey, Public Domain, via USGS Geomaps @ http://geomaps.wr.usgs.gov/pacnw/pacnweq/index.html

"Tsunami Forecast Model Animation: Cascadia 1700" (1:20)
Uploaded January 26, 2015, by PacificTWC (Pacific Tsunami Warning Center) to YouTube ~ URL: https://www.youtube.com/watch?v=4W2iUl0VB8c

The Earth's layer on which we live is broken into a dozen or so rigid slabs (called tectonic plates by geologists) that move relative to one another.
illustration of the world's tectonic plates by Jane B. Russell
W. Jacquelyne Kious and Robert I. Tilling, "Historical perspective," This Dynamic Earth (February 1996): US Geological Survey, Public Domain, via USGS Publications Warehouse @ https://pubs.usgs.gov/gip/dynamic/historical.html#anchor9449934

Part of the Pacific Ring of Fire, the Cascade Volcanic Arc extends for a distance of over 700 miles (1,100 kilometers) from southwestern British Columbia through Washington and Oregon to Northern California.
Subduction along Cascadia Subduction Zone is responsible for the arc's formation.
NASA WorldWind image; Black Tusk graphics: NASA World Wind, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Cascade_Volcanic_Arc.jpg

The Earth's layer on which we live is broken into a dozen or so rigid slabs (called tectonic plates by geologists) that move relative to one another.

the world's tectonic plates; W. Jacquelyne Kious and Robert I. Tilling, "Historical perspective," This Dynamic Earth (February 1996) — US Geological Survey, Public Domain, via USGS Publications Warehouse

Sources Consulted

Thompson, Jerry. 2011. Cascadia’ Fault: The Earthquake and Tsunami That Could Devastate North America. Berkeley, CA: Counterpoint Press.

Part of the Pacific Ring of Fire, the Cascade Volcanic Arc extends for a distance of over 700 miles (1,100 kilometers) from southwestern British Columbia through Washington and Oregon to Northern California.

NASA WorldWind image; Black Tusk graphics — NASA World Wind, Public Domain, via Wikimedia Commons

the end which is also the beginning — OpenClips, Public Domain, via Pixabay

Cascadia's Fault: The Coming Earthquake and Tsunami that Could Devastate North America by Jerry Thompson ~ Available via Amazon

Cascadia's Fault: The Coming Earthquake and Tsunami that Could Devastate North America

Me and my purrfectly purrfect Maine coon kittycat, Augusta "Gusty" Sunshine

Updated September 11, 2026

Comments

DerdriuMarrinerMay 28, 2026

The computer crashed afore I completed another component to my comment below.

The Oregon Department of Emergency Management contains the following url (https://www.oregon.gov/OEM/hazardsprep/Pages/Cascadia-Subduction-Zone.aspx) concerning the Cascadia Fault.

DerdriuMarrinerMay 27, 2026

For those asking about a Cascadia-Fault earthquake and tsunami, it aids analyzing such an event by accessing the Oregon Department of Emergency Management.

Does the afore-designated department defer to a far-off or soon-to-be date?

The Oregon Department of Emergency Management indicates the earliest incidence as perhaps 50 years from now.

DerdriuMarrinerMay 22, 2026

The below-addressed USGS article associates impending earthquakes with earlier, littler P and later, larger S waves.

Animal versus human senses respectively detect the P and the S versus the S waves.

The below-indicated Dawnay book identifies above-ground, ground-level, below-ground Mother Nature as involved in informational interactions across and among animal and plant species.

Wouldn't all that work well for watching for the Cascadia Fault?.

DerdriuMarrinerMay 21, 2026

The computer again crashed afore I constructed another component of my two comments below.

The below-cited USGS article contains a concise bibliography.

The first source inspired the afore-indicated article:

Kirschvink, Joseph L. (2000). Earthquake Prediction by Animals: Evolution and Sensory Perception, Bull. Seism. Soc. Am., 90, pp. 312-323.

Might it matter to mull earthquake-predictive behavior in the animal world?

Yes!

So why not try the free online options at the following urls:

https://pubs.geoscienceworld.org/bssa/issue/90/2
https://pubs.geoscienceworld.org/ssa/bssa/article-abstract/90/2/312/120521/Earthquake-Prediction-by-Animals-Evolution-and?redirectedFrom=fulltext
https://pubs.geoscienceworld.org/ssa/bssa/article-abstract/90/2/312/120521/Earthquake-Prediction-by-Animals-Evolution-and?redirectedFrom=PDF

DerdriuMarrinerMay 20, 2026

The computer crashed afore I conveyed another component of my comment below.

The USGS (United States Geological Survey) has an informative article that has the title "Can animals predict an earthquake?"

The afore-indicated information is iterated to us all through the USGS Earthquake Hazards Program through its section identified as Animals & Earthquake Prediction..

How might the afore-mentioned article be accessed?

Try the url https://www.usgs.gov/programs/earthquake-hazards/animals-earthquake-prediction

DerdriuMarrinerMay 19, 2026

Author Gabby Dawnay and illustrator Margaux Samson Abadie collaborated on Wild languages of Mother Nature for Wide Eyed Editions Tuesday, May 7, 2024.
Their 48 natural-world communicators included such sentients as animal and plant species.
Might the natural world mention to one another quite accurately such natural phenomena as Cascadia's Fault?

DerdriuMarrinerMar 7, 2026

The section Cascadia juggles three sea plates and one trench advises us that "Cascadia’s fault line from Cape Mendocino in northern California, through Oregon and Washington, to Vancouver Island off British Columbia in western Canada keeps low geo-historical profiles.
Cascadia’s 19 full margin ruptures of magnitude 9 and 22 partial margin ruptures of magnitude 8 in 10,000 years lead seismologists to rethink California’s upcoming mega-quake. Cascadia’s northern end from mid-Oregon to mid-Vancouver Island and southern end from Cape Mendocino to Newport, Oregon, manifest respectively recurrent intervals of 480 and 240 years. Dr. Kenji Satake of the Geological Survey of Japan and co-authors Kunihiko Shimazaki, Yoshinobi Tsuji, and Kazue Ueda note January 26, 1700, for Cascadia’s last mega-earthquake."

Couldn't it be quite compelling to collect Pacific-Coast native-american legends, lores, myths, stories and tales about the afore-considered Cascadia mega-earthquake of Tues., Jan. 26, 1700?

DerdriuMarrinerJul 26, 2017

blackspanielgallery, Amen! Some seismologists describe an alternating pattern between the eastern and western Pacific Rim and suggest that the North American side is overdue for an earthquake since the Asian side had the Fukushima quake.

blackspanielgalleryJul 24, 2017

At any plate boundary there is concern. Some earthquakes generate tsunamis, but others do not. his is because f the direction of the movement of the earth, how does the plate itself move. A plate that has vertical movement is more likely to form a tsunami than a plate that moves laterally.