A Serious Discussion On The Cascadia Subduction Zone and Latest Studies

reply to post by geotrician


Thanks! I have saved it to read later when I get a chance.

@John....I supose it would make sense that the area wouldn't have been as well monitored since they didn't expect a big one from there. Too bad...

reply to post by westcoast


No, it's very well monitored. But the slabs that are older and presumably drier tend not to have slow slow, and this falls in that category.

Originally posted by JohnVidale
reply to post by westcoast

 

No, it's very well monitored. But the slabs that are older and presumably drier tend not to have slow slow, and this falls in that category.

John, I presume you meant 'slow slip'. The Japanese scientists and politicians seem to have been obsessed with the Nankai trough region because of the 1923, 1944, and 1945 damaging quakes there. And the Tohoku event last year occurred where fairly consistent M7 max events suggested this was the biggest possible. They also did not have the long tsunami evidence from digging that they might have had. What they overlooked was the random nature of earthquakes and the fact that the Pacific Plate was going down at 4 cm/yr rather than the 2 cm/yr of the Phillipine plate under the Nankai Trough, which did exhibit slow slip and tremor.

writerfighter,
i invite you to use anything from my articles covering juan de fuca and cascadia, lisabona etc;
the great seattle fire article also relates to our situation,
let me find them for you:

nuclearnuttery.wordpress.com... ntists-could-be-looking-too-low-for-megaquake-epicenter/

**UPDATE** Can Humans Sense Remote Earthquakes or Hours-Away Quakes? BOTTOM. Also, Oregon Microplate Risk — Please Watch Closely if in PNW. **Mag 4.0 Strikes Across from Vancouver Island** Scientists could be looking too low for megaquake epicenter.
Posted on November 23, 2011

nuclearnuttery.wordpress.com... o-911-mayoral-corruption-a-problem-for-public-satefy/

FIREMEN AND FREEMASONS PLEASE READ: ARSON ACROSS AMERICA! Politics Make Strange Bedfellows, History Finds Strange Mayors — from London 1666 to Seattle Great Fire to 9/11, Mayoral Corruption a Problem for Public Satefy
Posted on January 29, 2012

nuclearnuttery.wordpress.com... 01-a-megaquake-precursor/

How Much Quake Does It Take to Trigger a Lateral Blast from an Elevated Active Volcano? Was Nisqually 2001 a MegaQuake Precursor? Also — Looking at the “Clathrate Gun Hypothesis” (for #s and giggles). How Do Developed Nations Plan to Fight Eco-Terror and Corporate Resistance to Fuel Alternatives?
Posted on January 6, 2012

**UPDATE@Bottom: The Lake NYOS Effect and Eco Terrorism Today** Cascadia Subduction Zone, Silent Earthquakes, Mid-Plate “THUNDER” Sounds, Megathrust Precursors, Needs More Study. AT BOTTOM: GLOBAL WARMING/CARBON FRAUD AND SEISMIC TERRORISM?
Posted on November 10, 2011

Nov 3rd UPDATE, Oregon Microplate 3.1 Quake — Oct 31 Studying “THE GONG EFFECT”. Seattle/Vancouver Island Region Not Quaking With Rest of “RING OF FIRE” REGION — Are we holding stress? **ALSO — LOOKING AT CHEROKEE RATTLESNAKE PROPHECIES**
Posted on October 31, 2011

AboveTopSecret.com Going Nuts Over Cascadia EQ Risk — I wasn’t the only one who “noticed”.
Posted on March 3, 2012

Recent Earthquake Activity on Mexico Border, Northern California Coast, Juan de Fuca Risk High. Also Looking at Alchemy, Basil Valentine, and His Words on Apollo and Diana
Posted on February 14, 2012

Cascadia Update – WIKIPEDIA reports UPGRADED RISK – Looking at “Transform Faults”, “Connected Faults”, “Domino Effect Seismicity”, “Subduction and Strike-Slip Disasters”, “Lateral Blasts and Masonry”, and “SUPERMOON”! Yay!
Posted on January 18, 2012

reply to post by nuclearnuttery

Maybe you should change your moniker to nuclearnutterynarcissism.

Ack, I found this thread all the way back on page 4.

This is the past 2 days of ETS. It's really far south. Then I noticed that the main tremor page at PNSN.org has 2 new locations: N. Vancouver Island and N. Central California. I'm glad to see the extension at both ends of the CSZ. What prompted the change, I wonder?


Is there any correlation between this paltry tremor activity (only 5.5 hrs/88 epicenters), and 5 tiny earthquakes near Mt. Shasta and Lassen Peak in the past week?

reply to post by Olivine


Steve Malone and Aaron Wech decided to extend the area of their analysis, so there are two new regions on the map.

I haven't looked closely at the pattern in California.

reply to post by Olivine


Hey Olivine! Thanks for the heads up on that. It would figure that after wishing that would happen for over a year, I happen to not check the tremors for a couple of days....and there you go.


I can only think that more information is better...that it may perhaps help to give a clearer picture. Especially since it looks to include some nice seismicly active areas to compare!

I know last year (or the year before?) Aaron had told me they wanted to extend it, but it was a matter of collaboration and resources. SO glad to see that it's happening!

Washington has been having some quakes pop up today. I was surprised to see that no one has posted them.



That was the latest. There was another earlier in about the same spot, same depth.

reply to post by AuntB


yup....there have been five there today. About 20 km from Mount Baker....

Quake list

O goody. My spidey sense just told me that the serious nature of this thread just went out the window.

reply to post by geotrician


You know, I resisted posting an equally sarcastic retort to your post because seeing is believing. Please friend me on Facebook and check out my timeline. You'll see that I predicted this morning's quake. My ability is very real, and if you scroll down my Facebook page timeline, you'll see just how real it is.

Pamela's Facebook page

reply to post by PamelaBritton2U


OOPS....I think you got this on the wrong thread.


I did however, want to make a comment here.

The two massive quakes today (and dozens of aftershocks) off-shore Sumatra are really something. John, I have been following your posts on facebook regarding the odd pattern of these shocks and the fact that they are so shallow. I find any large quake on the ring of fire of interest to us here in the PNW for obvious reasons. I believe we stand a good chance of learning from them....what do you make of the patterns today? How is this area alike and different from our own? I know you have said before that you do not believe in the triggering affect from long distances, but do you also feel that way in regards to the ring of fire? That a large release in one area may affect another?

Originally posted by westcoast
reply to post by PamelaBritton2U

 

OOPS....I think you got this on the wrong thread.

Alas, no. This nice person commented on page one of your thread (very bottom). I was rather miffed when I read it, but kept my comments to myself figuring that I'd be able to prove my words sooner or later.

Anyway, I love to read about the science behind the earthquakes so thanks for starting this (and other) threads.

reply to post by westcoast


We tend not to interpret any one instance of apparent correlations of widely spread earthquakes. When examining decades of data, we find that triggering of distant earthquakes is very uncommon, although it has been seen for small triggered events in several cases.

The new aspect of these two quakes last night is their size and complexity. The M8.6 and the M8.2 are now the two biggest recorded strike-slip earthquakes, and they struck is a place that was not an obvious thoroughgoing fault. I don't know what this means, exactly, except that every year we get less and less confident that we know what is likely to happen next.

reply to post by JohnVidale


Thanks for the frank response....I didn't know until just a bit ago that these were actually strike-slip quakes! Amazing. I ofcourse assumed it was a subduction quake.

I'm wondering if this might lead to some revisions of the current geology books?? I'm also wondering if this may affect the current estimates of potential quake sizes for our own strike-slip faults in the PNW?

reply to post by westcoast


It's too soon to tell how it will impact hazard estimates in the Pacific Northwest. Probably not too much, since it seems a rare event and not terribly dangerous, but it was definitely a surprise.

reply to post by JohnVidale


So another question for you! I have speculated as to whether or not the San Andreas fault was a result/symptom of the CSZ.....especially if the CSZ continues a bit further South than the current maps indicate (this would be supported by the deep tremors occuring further south than where it is now considered to end, IMO)

Is there any comparison between the fault that created the 8.6 and the San Andreas? If these strike-slip faults both sit close to the edge of a subducting plate, is there a potential to have some of the same mechanisms? It just really makes me think more about the potential for major quakes along other strike-slip faults. Could you imagine a 8.5 from the San Andreas? Especially since there are a couple of calderas near it.

Then there is ofcourse the Seattle Fault, the Nisqually fault and the big Southern Whidbey Island fault zone. I think they were estimating up a 7.5 on the Seattle fault (which literally runs under safeco field). What in the world would a 8.6 under the heart of Seattle do, or right through Puget Sound?

I don't want to speculate too much....but I just think that in light of the Sumatra quake, these are legitimate questions now.

reply to post by westcoast


This is complicated, and we don't know the answers yet. Specifically, we don't yet know why the magnitude of this recent events was so big. It might have broken deeper than expected, 20-40km instead of 10-15. The fault might be longer than some estimates, 400-500 km rather than 250, or maybe even a set of faults. The slip might be much greater than expected, maybe 40-80m rather than 10-20m.

Until we know better what happened, it is too soon to apply lessons to faults elsewhere.

New dangers and earthquake risks found in Washington
www.msnbc.msn.com...

I saw this article today and thought this was the perfect reason to relive this thread. The article is stating that there are now 3 new faults in the Washington area. Please note this is a MSM article so hype and misquotes are common but it is an interesting article.

reply to post by AuntB


Thanks for the link. I am slacking!

So we have had two more quakes this morning in that same region off-shore vancouver. A 4.4 and then a 4.0 in about an hour of each other. Those, combined with the 4.4 and the 3.9 from a few days ago.....makes me wonder if something bigger is coming.

Link to quake list


Take a look at the depths. Either they are coming from different faults although they are very near each other, or the shocks are getting shallower. Hmmmm.....