PNW Geologists Learn From Other Earthquakes

 

I would like to applaud geologists for always looking to improve our reporting and forecasting for a 9.0 earthquake.

One thing to note, the state of Oregon re-forecast their tsunami maps after the Japanese earthquake. I assume they took into account how the water flowed in Japan and compared it to the topography along our coastline. For instance, before 2008 the map essentially said the people of Coos Bay would be affected along the beaches (which are a distance from the actual town) and the bay would possibly have a surge similar to the 11-foot tides in the winter months (with 11-foot tides in Coos Bay, the water will reach Highway 101 slightly but not much).

After 2011, the Japanese earthquake showed a more aggressive tsunami and US geologists realized this could happen along our coastline. So they reforecast. Now, a tsunami in Coos Bay can reach all the way out into Libby through the sloughs that feed from the bay. It seems crazy… I would have to drive 15 minutes to get to a beach from the area yet a tsunami will wind its way through various sloughs, tributaries and marshes overflowing into parts of some secluded inland areas. Following the geologist’s logic and looking at the land and understanding the area (my grandparents owned the large ranch in the Libby area where the tsunami inundation zone essentially “ends”) – it makes absolute sense. It’s marshy most of the year even during the summer months. This is conjecture on my part, but the land likely dropped from the 1700 earthquake making it a marsh similar to some parts of Anchorage after 1964. The terrain is similar in texture.

The same goes for a tsunami that might reach Coos Bay’s Blossom Gulch elementary school – which was illustrated in the state’s re-forecast after the Japanese quake. Again, it seems outlandish since you can’t even see water from the grade school but I appreciate the geologists taking into account what happened in Japan and forecasting how that would look along areas such as Coos Bay.  If you live there and understand the lay of the land – it’s logical and makes sense.  I assume it’s the same for other coastal communities.

Thank you to the many subject matter experts and researchers who are working to save lives.

A Prediction of 10,000 deaths in the Northwest

I read a study recently discussed on KGW which stated scientists estimate 10,000 people in the Northwest will perish from this megaquake…. this gives me chills. I’m not an overly religious person but I actually catch myself saying a little prayer that my children are not among the casualties. I really, really pray they always remain safe and this earthquake doesn’t occur in their (very long) lifetime.

Unfortunately, I can see this large body count happening after growing up along the coast. The news of the earthquake is a slap in the face and many live in denial. I feel there was almost a false sense of security that “we live God’s country” – we don’t have tornadoes (BTW, I read that one did touchdown in Coos County about 30 plus years ago), no hurricanes (OK, we will not count the Columbus Day storm, where winds at Cape Blanco were well over 145 mph), no black widow spiders (we have the Hobo Spider and they are nasty little suckers), but all in all…. it’s a pretty tame environment or at least so I thought.

Many residents may think that they can muscle through this event, which they may and I hope they do, but without knowing where is safe and where landslides

English: Damage from the Columbus Day Storm of...

English: Damage from the Columbus Day Storm of 1962 (Photo credit: Wikipedia)

may occur, how can you truly be safe?

I implore anyone living along the coasts of Washington and Oregon… know the path of a tsunami whether it’s from a local earthquake or a distant one. (The paths may vary depending on the location of the seismic activity) It will surprise you.

Have a plan and execute it flawlessly.

Evacuation Maps:

Oregon

http://www.oregongeology.com/sub/earthquakes/coastal/Tsubrochures.htm

Washington

Click to access ger_tsunami_inundation_maps.pdf

KGW Article:

http://www.kgw.com/home/Report-makes-chilling-forecast-on-NW-quake-198444741.html

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