Monday, June 22, 2015

Tsunami Warnings

The state of Oregon, as you may know, is situated along the Cascadia Subduction Zone, where the Juan de Fuca geologic plate slides underneath the North American Plate at a rate of about 2 inches a year.  This has the potential to cause earthquakes when the movement builds up enough pressure, and earthquakes can cause tsunamis.  Now this is true along most of the west coast, but in Oregon they have decided to get serious about tsunamis.  In fact, to all appearances, Oregon has gone absolutely crazy about tsunamis. Every time the road approaches the ocean there is a sign telling you that you are entering a tsunami danger zone. When you drive up a hill 30 feet they thoughtfully put up another sign to let you know you are leaving the danger zone and can breath a little sigh of relief.  Every beach park and little town has signs indicating where the tsunami escape routes are. One would assume that tsunamis are a huge problem in Oregon. They must happen every other week or so. Out of the 10 leading causes of death in the state, you would have to guess tsunamis come in at about number three. So, when was the last earthquake along the Cascadia Subduction Zone?  Well, it turns out it was at about 9 PM on 26 January, 1700.  Yes, you read that right, one-seven-zero-zero.  Seventy-six years before the signing of the Declaration of Independence.  So all of this huge brouhaha is in preparation for an event that none of us have ever witnessed, nor our grandfathers, nor their grandfathers nor theirs. The estimate is that this sort of thing happens about once every 500 years or so. So, what the heck happened here? Why are the citizens of Oregon living in constant fear of death by drowning?

What happened was the 2004 tsunami in Southeast Asia. The state government here started thinking about what would happen if a large earthquake did occur along that big subduction zone just off the Oregon coast. It would be horrific, with floods extending up every river estuary for miles.  And Oregon has a LOT of river estuaries.  The politicians decided they owed it to the electorate to do something about this potential catastrophe.  The solution, apparently, is to put up signs. When a 100 foot high wall of water hits the beaches, signs will take care of the problem. The people of Oregon can sleep better tonight knowing they have signs between them and watery disaster.  Of course, IF an earthquake DOES occur along the Cascadia Subduction Zone, it will take the resulting tsunami under 2 minutes to reach the Oregon coast, so you'd better read those signs pretty damn quick!

Now, in all fairness, the Cascadia Subduction Zone is not the only fault line on the planet and a tidal wave can travel a long, long way.  The reason we know something about the 1700 quake here is because the resultant tsunami flooded Japan on the other side of the Pacific Ocean (and they kept pretty good records at the time).  The Alaskan earthquake in 1964 flooded Newport Harbor and killed 5 people camping on the beach a few miles north.  So tsunamis can and do occur and having some sort of plan in place is not completely idiotic.  But there are many natural disasters that are more likely to find you during your lifetime and if you do happen to have the misfortune to be sitting on the Oregon coast the next time the Cascadia Zone slips, probably the only real plan is to kiss your butt goodbye.


We first visited the Alsea Bridge Interpretive Center in 2002 when Christopher was 12.  The museum had a bridge model made out of wooden blocks showing how, if you put them together just right they will form an arch that will support itself against gravity.  So he carefully placed all the blocks and - voila...

a bridge.

I did not interfere in this early engineering enterprise of his, but when Vicki and I returned in 2009 I decided to take a try at bridge construction.  I mean, my 12 year old did it, how hard could it be?  So I carefully placed all the blocks and - voila...
 
a pile of wooden blocks.  Hmmf... there must be some trick to it.

So this trip we decided it was Vicki's turn to construct the bridge.  It really is pretty exacting and I told her not to feel bad if it collapsed the first try or two.  She's not really very good at this kind of physical problem solving.  So she studied the problem for some time and then carefully placed each block in place, raised the structure and - voila, the bridge stood perfectly.

But only for a short while.  It turned out not to be structurally stable enough to withstand the environmental stresses it was subjected to.


We have spent the last month staying at the Chinook RV park about 3 miles inland from Waldport along the Alsea Highway.  This is a beautiful little RV park with only about 25 camping sites, right on the Alsea River estuary.  They have a grassy/marshy area next to the river where various birds carry out their birdish activities for the amusement of the campers and your dogs are allowed to explore off leash (but we were warned that the eagles on the other side of the river had been known to try and carry off tiny dogs like ours).  Occasionally an elk could be seen in the marshland on the opposite shore.  It was fun to sit out with binoculars and watch the wild life.  The owners were friendly and very helpful with getting our mail delivered and what-not.  Overall it was one of the most pleasant RV camping experiences we have ever had.  If you are going to be spending time in this area, check it out.

From the time we arrived we kept hearing the constant hooting of an owl.  We couldn't figure out where he was exactly but he sure made a lot of noise.  Finally, last week we spotted him.  Here is our owl...It's a Mourning Dove.  They make a who-whoooooo-who call and are the most common "hooting" bird in America.  Oh well, what do we know?

On Saturday we packed up and headed north.  We are going along in baby steps because we are not in any hurry, but our eventual destination is the Olympic peninsula where we will stay for another month.  I leave you with a collection of Oregon Coast pictures to tide you over for now.
 
 
 




 
 










2 comments:

  1. The Oregon coast area is one of the prettiest anywhere. Really nice that you can just take your time and enjoy it. Way to go Vicki!!! Maybe when the tsunami hits you can swim towards the signs.

    ReplyDelete
  2. Not just the 1960s and the 2004 tsunami. It was predicted that the 2011 tsunami created by the Tōhoku earthquake in Japan would hit the Oregon coast before anywhere else on the West Coast, early the morning after. No one really knew how big the waves might be...As it turned out, once again Crescent City's fishing harbor was destroyed and a marina in Santa Cruz was severely damaged. Oh, and I think someone got washed out to sea. While the signs along the Oregon coast are laughable (who reads them until they need them, right?), it's someone's well-intended notion of a way to keep us aware that it *could* happen. Unlikely, but...who would have guessed that a 6.9 would rock the entire SF Bay Area and Santa Cruz County during the opening of the 1989 World Series...

    ReplyDelete