Pac NW Earthquake and Volcano thread

[WESTSEATTLEGUY]

Originally Posted by Joosanova

On February 23rd 2009 Mt. Rainier lost the title of most dangerous volcano to the Massive Caldera that encompasses 95% of Yellowstone N.P

That's so stupid. Sure Yellowstone is dangerous, but no one living in the Yellowstone vicinity is in imminent danger of a massive eruption which is unlikely due to the size of the massive caldera. But millions of people are reminded everyday in the PAC NW of the unstoppable danger that looms over them which is Rainer. And it's not like yellowstone has a concentration of large high tech populated cities that rim its base. Whoever made that statistic should really rethink what they consider 'dangerous' as the loss of life with a Rainer eruption would be far more greater than a Yellowstone catastrophe.

[RMacherat]

Uh-oh. Discord has come early to our nice new thread. I'll referee. Rainier will kill more people immedately, though not the hundreds of thousands that some predict. It will be a huge mess for us, for sure. Long term, Yellowstone will kill more, like everybody.

[pwalker]

Originally Posted by RMacherat

Uh-oh. Discord has come early to our nice new thread. I'll referee. Rainier will kill more people immedately, though not the hundreds of thousands that some predict. It will be a huge mess for us, for sure. Long term, Yellowstone will kill more, like everybody.

True. The super-mega-whatever you want to call it Yellowstone eruption would be catastrophic world-wide. The good news is the last one was over 600,000 years ago, and the one before that, 2 million years ago. The chances of this happening during any of our lifetimes is extremely small.

[Backstrom]

Despite the heralded destruction of Cascadia earthquakes, I highly doubt that our "tallest buildings" would collapse. What we're likely to see is the decimation of smaller brick and load-bearing buildings, those that rely on compressive strength. The taller, modern and postmodern steel buildings will *probably* be spared-- albeit a LOT of shaking at the top floors.

As far as when it will it, I averaged out the intervals between the five Cascadia earthquake since 600BC, and its about a 460 year interval on average--so we're still in the early days. By as each minute goes by, the probability of it happening increases.

[CrazyAboutCities]

I heard if Mt. Rainer erupt... It will not affect Seattle metro area much but it will destroy most part of Portland metro area and block I-5.

[Bond James Bond]

I don't think Mt Rainier is a threat to Portland at all. Look at a map. Tacoma? Yes. Portland? No.

[Backstrom]

The only threat Portland would likely face is fallout from ash. Tacoma and the South Puget Sound will get the brunt of the mudslides likely to ensue from a Rainier eruption. Towns situated in the river valleys that flow into the Sound are at most threat. Orting, for example, would probably have a good chance of being wiped out. And the lahars would most likely take the path of flowing straight through the Port of Tacoma into Commencement Bay.

[pwalker]

Originally Posted by Bond James Bond

I don't think Mt Rainier is a threat to Portland at all. Look at a map. Tacoma? Yes. Portland? No.

Yes, that is correct. The lahars would flow basically into the Puyallup valley, then perhaps on to Tacoma. Prevailing winds would blow ash normally to the east-northeast, much like Mt. St. Helens. However, any deviation might cause significant ashfall over the Seattle metro, or with offshore winds, SW Wash, and/or Portland, as backstrom mentioned. I'm not sure there would be any structural damage in Seattle, though. That would have to be a worst-case scenerio.

[Black Box]

Was not here for the 2001 quake, but that seemed bad enough. It could have been much worse. I hope I die before it happens and before Mt. Rainier blows.

[Joosanova]

MASSIVE 7.9 Earthquake off the SW coast of New Zeland late last night...

No immediate reports of damage or injuries but a H-U-G-E wake up call for anyone living in a seismic region....

The one saving grace is the quake had a depth of 21.7 miles most likely limiting any catastrophic damage.

[CrazyAboutCities]

Do not forget that Portland is almost surrounded by three major volcanoes (Mt. Hood, St. Helens, and Mt. Rainier) That is highly chance that Portland metro would be damaged badly if any one of them erupts. I learned about it from my environment science class around two years ago. I am glad Seattle isn't that close to the volcanoes but I believe that Seattle metro area could be affected by earthquake, ashes and mudslide or lava (only if they have it).

[WESTSEATTLEGUY]

St. Helens or Rainer if they erupted would not effect Portland. Mount Hood could do some damage but all it's rivers are tributaries to the Columbia so the lahars would bypass the PDX metro completely.

The only thing they are in danger of is ash which would also be unlikely due to the normal easterly wind pattern.

[old_smithy]

Originally Posted by just4ivaylo

A big one's going to hit soon.

This may, or may not, provide comfort to folks but Seattle will not have another big (6.5 or greater) earthquake as long as I am living here. For the last 45 years I was a resident of any city on the West Coast of the US when it had an earthquake of 6.5 or greater. The first was the San Fernando Valley quake in 1971. I was 11 years old and about 45 miles from the epicenter. The next large quake was the World Series Quake in Oakland in 1989. I lived across the bay in San Franciso.

In 1992 I moved back to Los Angeles and on Martin Luther King Day in 1993 (1994?) we had the Northridge quake. In 1999 I moved to Seattle and in 2001 we had the Ash Wednesday quake.

My friends call me the human earthquake predictor. I prefer to think that the earthquakes are following me. Either way, Seattle has had it's quake so we are all safe until the next time I move. I'd really like to go back to SF, but my friends who live there won't let me. Go figure.

[pwalker]

Originally Posted by old_smithy

This may, or may not, provide comfort to folks but Seattle will not have another big (6.5 or greater) earthquake as long as I am living here. For the last 45 years I was a resident of any city on the West Coast of the US when it had an earthquake of 6.5 or greater. The first was the San Fernando Valley quake in 1971. I was 11 years old and about 45 miles from the epicenter. The next large quake was the World Series Quake in Oakland in 1989. I lived across the bay in San Franciso.

In 1992 I moved back to Los Angeles and on Martin Luther King Day in 1993 (1994?) we had the Northridge quake. In 1999 I moved to Seattle and in 2001 we had the Ash Wednesday quake.

My friends call me the human earthquake predictor. I prefer to think that the earthquakes are following me. Either way, Seattle has had it's quake so we are all safe until the next time I move. I'd really like to go back to SF, but my friends who live there won't let me. Go figure.

That's funny. One slight correction, though. The Bay Area World Series quake in '89 was at Candlestick in San Fransisco, not Oakland. It was the "Bay Bridge series", and ironically, the Bay Bridge had some of the most dramatic damage from that quake. I remember the tv coverage, all the networks went live for hours that evening.

[CrazyAboutCities]

Originally Posted by old_smithy

This may, or may not, provide comfort to folks but Seattle will not have another big (6.5 or greater) earthquake as long as I am living here. For the last 45 years I was a resident of any city on the West Coast of the US when it had an earthquake of 6.5 or greater. The first was the San Fernando Valley quake in 1971. I was 11 years old and about 45 miles from the epicenter. The next large quake was the World Series Quake in Oakland in 1989. I lived across the bay in San Franciso.

In 1992 I moved back to Los Angeles and on Martin Luther King Day in 1993 (1994?) we had the Northridge quake. In 1999 I moved to Seattle and in 2001 we had the Ash Wednesday quake.

My friends call me the human earthquake predictor. I prefer to think that the earthquakes are following me. Either way, Seattle has had it's quake so we are all safe until the next time I move. I'd really like to go back to SF, but my friends who live there won't let me. Go figure.

It is 1994. I lived in San Diego when it happened.

[Backstrom]

Originally Posted by old_smithy

This may, or may not, provide comfort to folks but Seattle will not have another big (6.5 or greater) earthquake as long as I am living here. For the last 45 years I was a resident of any city on the West Coast of the US when it had an earthquake of 6.5 or greater. The first was the San Fernando Valley quake in 1971. I was 11 years old and about 45 miles from the epicenter. The next large quake was the World Series Quake in Oakland in 1989. I lived across the bay in San Franciso.

In 1992 I moved back to Los Angeles and on Martin Luther King Day in 1993 (1994?) we had the Northridge quake. In 1999 I moved to Seattle and in 2001 we had the Ash Wednesday quake.

My friends call me the human earthquake predictor. I prefer to think that the earthquakes are following me. Either way, Seattle has had it's quake so we are all safe until the next time I move. I'd really like to go back to SF, but my friends who live there won't let me. Go figure.

Move out to the Montana Badlands, smithy! We'll see how well you do there!

[silence.kit]

Originally Posted by Joosanova

Not trying to make light of your wanting need for major quake to NOT occur in our lifetime but..... IT WILL HAPPEN!!!!

NOT a matter of " IF " but " WHEN "

Additionally we are unfortunately screwed seeing as how we are located in 1 of only 3 places in the world ( primarily within the ring of fire ) where MAJOR subduction zone quakes have occurred and alas we are the only region in the world that has MEGA-Thrust quakes where indescribable damage has occurred and will occur again.

One such mega thrust quake occurred around 300 a.d and lifted the central and north coast of Washington state a staggering and unprecedented 60 feet....

I too pray it doesn't happen in our lifetime but the odds are not in our favor....

Just remember what happened on February 28th 2001 and know that a quake of that magnitude and duration will occur again if not stronger, longer lasting and with more devastating implications.

The next subduction zone quake to occur in our area will make Mexico City pale in comparison to what happens here..... when it DOES occur.

You sound like those silly programs on the History channel.

"Not a matter of if, but a matter of when."

[RMacherat]

More research is needed.

[Joosanova]

Originally Posted by silence.kit

You sound like those silly programs on the History channel.

"Not a matter of if, but a matter of when."

Well... I may sound " Goofy " but what I said is true and will be proven at some point in time whether it's now or in the future.

HISTORY WILL repeat itself.

[Backstrom]

Originally Posted by Joosanova

Well... I may sound " Goofy " but what I said is true and will be proven at some point in time whether it's now or in the future.

HISTORY WILL repeat itself.

Yeah, it will, but we're actually not in the window for the next Cascadia earthquake yet. Since 600BC, the smallest interval between two major megathrust earthquakes in this region was 390 years-- over the 5 earthquakes, the average interval is 460 years. If I had to chance a guess, it would probably happen around 2100-2150.