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dgavin
2010-May-07, 06:54 PM
One of the unnamed Sea Mountains on the Juan De Fuca plate experinced a whooping 5.1 earthquake about an hour ago ~ 10:48 am PDT.

Location: http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=44.407N+129.339W&sll=44.407,129.339&sspn=0.169723,0.227623&g=44.407+129.339&ie=UTF8&ll=44.613934,-129.193726&spn=2.705947,3.938599&t=h&z=8

Although this is close to the Blanco fracture zone, it's an unkown at this point if it is Tectonic or Volcanic.

Gillianren
2010-May-07, 07:06 PM
Ah. No wonder I didn't feel it--for the curious, it's out west of Coos Bay, Oregon, a couple hundred miles offshore.

korjik
2010-May-07, 07:07 PM
well, the Mayan calendar ends in 2 and a half years...

:D

dgavin
2010-May-07, 07:14 PM
No Tsunami warnings have been issued, although informational statement was released by NOAA.

A Magnitude 3.1 and 3.9 earth quake just /now/ occured in the same region.

dgavin
2010-May-07, 07:43 PM
The 3.1 was Upgraded to 3.8 Mag.

There was another 3.9 and 4.3 earth quake in same region. These are too strong to be normal aftershocks. Still unknown if Volcanic or Techtonic. Depth of events have decreased from 28km to 10km.

dgavin
2010-May-07, 08:24 PM
Another Quake Mag 4.4 in same region, back to 28km+ depth.

dgavin
2010-May-07, 09:43 PM
Latest Log, with updates to depths and Magnitudes.

MAG UTC DATE-TIME y/m/d h:m:s LAT deg LON deg DEPTH km Region
MAP 4.4 2010/05/07 20:02:19 44.496 -129.418 10.0 OFF THE COAST OF OREGON
MAP 3.9 2010/05/07 19:15:59 44.527 -130.659 10.0 OFF THE COAST OF OREGON
MAP 4.3 2010/05/07 19:03:31 44.536 -129.557 10.0 OFF THE COAST OF OREGON
MAP 4.4 2010/05/07 18:55:04 44.508 -130.052 10.0 OFF THE COAST OF OREGON
MAP 4.2 2010/05/07 18:51:00 44.490 -129.557 10.0 OFF THE COAST OF OREGON
MAP 3.9 2010/05/07 18:48:37 44.458 -129.107 10.0 OFF THE COAST OF OREGON
MAP 4.5 2010/05/07 18:43:08 44.456 -129.410 10.0 OFF THE COAST OF OREGON
MAP 4.4 2010/05/07 18:41:55 44.407 -129.456 10.0 OFF THE COAST OF OREGON
MAP 5.1 2010/05/07 17:46:15 44.396 -129.437 10.0 OFF THE COAST OF OREGON

Swift
2010-May-08, 03:26 AM
You know, my wife and I are planning a trip to the Pacific Northwest this fall. Between this and Mount Hood, I might have to change our plans to the beautiful beaches of the Gulf Coast. ;)

Gillianren
2010-May-08, 03:33 AM
They are awfully beautiful beaches. If you choose to visit scenic Olympia . . . well, we don't really have much in the way of beaches. But you can come by for dinner!

jj_0001
2010-May-08, 08:44 AM
There are some really beautiful beaches out on the Olympic Peninsula and Oregon Coast.

Hmm, where is my shot of Ruby Beach?

http://i238.photobucket.com/albums/ff228/jj_0001/rubybeach.jpg There ye go.

As to Hood? Well, you could drive down to Ca. if you needed to get an ash-free airport, and anyhow, volcanos do this all the time, and usually don't go off.

The south edge of the Juan de Fuca plate? It seems to shake every month or so.

geonuc
2010-May-08, 10:06 AM
The USGS doesn't have a 'beachball' for this quake (why?), but it is right next to the transform fault which has exhibited only transform-related strike/slip movement in the recent past.

http://neic.usgs.gov/neis/bulletin/neic_vzbx_m.html

dgavin
2010-May-08, 11:19 PM
Seam to be fault related, and nothing new today from it. Still all but one of the events was dirrectly under a Sea Mount. All told it looks like it relesed as much energy as a single 6.0 quake.

Jens
2010-May-10, 02:52 AM
One of the unnamed Sea Mountains on the Juan De Fuca plate experinced a whooping 5.1 earthquake about an hour ago ~ 10:48 am PDT.


Whooping? You mean like the cough? Or do you mean "whopping"? If so, is 5.1 really so big?

BTW, we had an interesting earthquake during lunch yesterday. It was just 4.0, but it was really right below us. There was no shaking, but we felt these kinds of thuds coming up from the ground. The epicenter was like 40 km under us.

Gillianren
2010-May-10, 03:59 AM
5.1 is not that big. However, a whooping earthquake would be interesting to experience. Much more unusual than the ordinary rumbling ones.

dgavin
2010-May-10, 07:04 PM
Yes well, while whooping quakes might be a bit more entertaining the whopping ones, I had ment the latter:P

Looks like this seiries is over, still nothing since the last 4.4 on Thursday. Neither USGS or NOAA has made any sort of statements yet.

So as it sits it's looking like this is transform fault activity, as mentioned by geonuc, even though most of these occured under a Sea Mount its very unlikely this is releated to volcanism of a it.

dgavin
2010-May-13, 06:25 PM
There was another 5.1 Mag Quake on the Jaun de Fuca Plate off Oregon coast, this time located in the North Gordo (http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US10/37.47.-130.-120.php) region.

Again no tsunami warnings will be issued for this event.

dgavin
2010-May-14, 06:50 PM
Just a followup on the new 5.1 Quake from yesterday , it was followed by a 4.1 quake in the same region and then by a 2.7 in the South Gordo area.

dgavin
2010-May-15, 02:22 AM
A busy quake day for the oregon, another 4.1 and then 4.0 in the North Gordo region of the Jaun de Fuca plate.

Quite a few meduim sized quakes in the last month on this plate. Haven't heard of a historical president for these size of quake's in the quantity there happening, so don;t know what to make of it, other then as Vulancs might say, "Fasinating."

dgavin
2010-May-19, 07:14 PM
Nothing new to report here.

However I did go through the historic quakes data a bit over the weekend, and actualy quake swarms of these sizes are entirely normal for the region. The plate seems to produce very few quakes under a 3.0 magnitude historically.

This might be due to the lack of a siemographs near the active regions of the plate, but I don't think that is the case these days. The Mt Hood 2.7 quake was picked up easily on Crater Lake and Mt. Shasta siesmographs, which is further in distance then the events were to the on shore siesmology stations.

dgavin
2010-May-21, 01:30 PM
One more smaller quake last night 3.4 mag at the south transform fault between Jan de Fuca Plate and the Pacific Plate.

Over all an intresting series of events, starting with a single quake on the north of the plate roughly east of seattle, followeed by swarms of mid range earth quakes that slowly seem to migrate south. Can't say I've ever heard of Jaun de Fuca quite being this active EQ wise before, It's allready hit it's yearly average of quakes in just a matter of three weeks. I do not think it portends anything at this point.

dgavin
2010-May-25, 01:08 AM
Another 3.0 along the transform fault between Jan de Fuca Plate and the Pacific Plate today. A bit closer to the coast then the last one.

geonuc
2010-May-25, 04:14 PM
I wonder if all the stress being relieved at the transform fault will be transferred to the subduction zone? In other words, as one section of the micro-plate boundary loosens up, the leading edge gets more stressed.

dgavin
2010-May-26, 03:58 AM
Geonuc

As the North to south migration of the swarms alonth the transform regions do indicate some sort of release of stresses there, I think it's safe to say the pressure might be trasfered towards the direction of the subduction region. Not much is really known about the Jaun de Fuca Subduction zone and plate historically though, other then the Native's legends of the 'Thunderbird' which might of been a description for a megatrust event.

It's only been recently monitoed (past 30 years or so) by siesmographs so there are a lot of unknowns about this tiny, state sized tectonic plate. But what you are wondering, makes sense to some degree from what this swarm event is doing.

dgavin
2010-May-27, 06:52 PM
A minor 2.8 Quake today at the junction of the Jan De Fuca, North American, and Pacific Plates. Again eastward location from pervious. I think you have the right of it geonuc, its starting to look like a gradual migration of plate stresses.

dgavin
2010-Jun-05, 10:23 PM
Three more quakes at the south junction of Jan De Fuca and Pacific plates today, largest being 4.2 mag.

dgavin
2010-Jun-09, 07:24 PM
There were a few more minor quake following my last post, not very notable.

However today there was another 4.4 Magnitude quake located back in the same region of the originally posted about 5.1 Quake.

dgavin
2010-Jul-26, 06:39 PM
Well Jan-de-Fuca isn't quite done yet. There was a 5.1 EQ a few weeks ago on the canadian portion of the plate, followed by a 4.7 in the same region yesterday.

dgavin
2010-Jul-28, 07:19 PM
About 3 hours ago there was a 5.3 quake just 85 miles WNW of Coos Bay Oregon, just 15 miles W of the Juan de Fuca/Contiental Plate interface. No Tsunami warning issued for this quake.

Location on Google Maps (http://maps.google.com/maps?q=43.7704+-125.8025(M5.3+-+OFF+THE+COAST+OF+OREGON+-+2010+July+28++16%3A12%3A06+UTC)&ll=43.7704,-125.8025&spn=2,2&f=d&t=h&hl=e)

Although I don't really like saying this, these medium sized quakes over the last few months are now about double of the yearly average. I think there is a small, very small chance at this time these might be precursor events to a megathrust quake event.

jlhredshift
2010-Jul-28, 11:14 PM
About 3 hours ago there was a 5.3 quake just 85 miles WNW of Coos Bay Oregon, just 15 miles W of the Juan de Fuca/Contiental Plate interface. No Tsunami warning issued for this quake.

Location on Google Maps (http://maps.google.com/maps?q=43.7704+-125.8025(M5.3+-+OFF+THE+COAST+OF+OREGON+-+2010+July+28++16%3A12%3A06+UTC)&ll=43.7704,-125.8025&spn=2,2&f=d&t=h&hl=e)

Although I don't really like saying this, these medium sized quakes over the last few months are now about double of the yearly average. I think there is a small, very small chance at this time these might be precursor events to a megathrust quake event.

Is it possible that the built up strain is being released in small chunks? (yeah, I know, we'll know, after.)

dgavin
2010-Jul-29, 12:02 AM
Is it possible that the built up strain is being released in small chunks? (yeah, I know, we'll know, after.)

Basicaly thats the rub. It could just be small releases of pressure which is the most likely case, or it could be precursor events to a megatrust, the unlikely case.

However we won't really know till after like you said.

The frequency of quakes in the short time frame is unusual. Thats about the only thing that can be said point positive about it.

dgavin
2010-Jul-30, 02:00 PM
I've been researching things to find any alternative explaination about why suddenly there are so many medium sized events here in the last few months, as opposed to what i said three posts ago.

It seems that in January/Febura, NOAA released a series of under water siesmographs onto Jaun De Fuca plate. While that might account for an increase in reporting of smaller events, I don't think that would account for an increase in reporting the 4-5 magnitude events.

So were still looking at an unusual amout of medium sized quakes, without much indication as to what it might lead too yet.

dgavin
2010-Aug-16, 06:35 PM
Another 4.5 on the South Gordo portion of Jaun de Fuca plate today.

dgavin
2010-Aug-17, 07:34 PM
And another 4.2 quake today at the northern most interface of North America (Canada), Pacific and Jaun de Fuca plates.

dgavin
2010-Sep-23, 06:59 PM
3 more quakes this week after a long peorid of quiet, 3.3, 3.6 and 4.4 magnitudes.

*edit to add*

Another quake today, 3.7 Mag.

dgavin
2010-Oct-04, 06:37 PM
4 more Quakes, two today. 4.5 followed by a 4.8 on the norther edge of plate today, a 3.3 and 2.1 on the mid and south parts of plate ealier this week.

I finnaly found out that the seemingly sudden appearence of these quakes and continuing frequency of them, is due to the recent installation of ocean based Siesmographs. On average Jaun De Fuca has around 600 quakes a year, typically 3 of which are over 5.0 magnitude. Before this year they were only detected through Hydrophones left in operation after the last war (WW2) so the data was only availabe through US Navy channels.

So now we have real time ocean based Siesmographs in operation now, and seeing the results of that.

dgavin
2011-Mar-24, 07:59 PM
Nothign to worry over, but just an FYI.

Toady at 8pm Pacific Time, many siemographs from nothern Calif, to southern Canada picked up a slow/slip tremor signature of the Jaun-de-fuca Subduction zone. The strogest readings were from the Mid. Oregon stations.

These do happen occasioanly, but this is the first time I've seen this happen since I started watching webicorders. The wave forms had a frequency span measuring in the 30's of seconds. Nice to finaly catch one of these types of background events.

grapes
2011-Mar-24, 08:04 PM
Still reading. :)

Ara Pacis
2011-Mar-24, 09:31 PM
Is this the location from which the infamous 1700 Cascadia subduction zone megathrust earthquake and tsunami originated?

dgavin
2011-Mar-25, 12:24 AM
Ara,

My method of location is a bit rough and based more on signal stregths and arrival times, then on the proper methods (As i'm not trained well enough in those fomulas yet). The strongest signals were alost directly below 3 Sisters and Newberry calder areas, while the arrival timing puts it bit more towards the coastal region of Oregon.

So if i'm not to far off, it is south of the 1700 event which occured mostly along the washington coast.

dgavin
2011-Apr-12, 07:23 PM
Besides the Mt. Axial activity along the Jaun De Fuca ridge, there was a 3.6 quake off the coast of Eureka, Calif., and a 4.3 just off shore of the calif/oregon border.

I'd almost have to say these are follow up events to the slow slip event from Mar 24th.

It's been quiet on the plate for a number of months, and then activity picks up again just after the slow/slip event. The quakes are all located at the spreading/transform boundries between pacific plate, and Jaun De Fuca plate. This also makes some sense if the slow/slip process reduces enough stress, then the spreading of the Jaun De Fuca ridge will be less impeeded.

dgavin
2011-Jun-21, 06:59 PM
June 18th a 4.8 and a 4.2 about 1 - 5km's from the rift zone.

Today a 3.8 along the mid plate transfrom zone.

dgavin
2012-Feb-05, 06:09 AM
Today (Sat Feb 4th) there was a 2.6. Quake off the Oregon Coast at 11 am, followed by a 4.3 near by that at 11:30am and then a 5.7 Quake at 12 noon, off the coast of Washington/Canada.

The 5.7 seems to be a standard Strike/Slip fault, the others have no movement tensors posted yet.

Tensor
2012-Feb-05, 07:08 AM
... have no movement tensors posted yet.

Not surprising, I've been ill and spend most of the day in bed, so yeah, no movement here.:p :D

dgavin
2012-Feb-05, 04:56 PM
Not surprising, I've been ill and spend most of the day in bed, so yeah, no movement here.:p :D

:doh:

dgavin
2012-Feb-08, 07:34 PM
A small 2.2 micro earthquake today, off oregon southern coast. Thats 4 quakes this week so far on the Jaun De Fuca plate. Nothing untoward about this activity though.

This was a nice one to look at in that it showed up on a number of broad band and volcano's seismographs, in spite of it's small magnitude. Noticed it first on Newberry/Pine Mountain stations, and can even follow and the see the signal arriving earlier the closer to SW coast stations are.


As far as Tensor movement goes, hopfully our Tensor is up and moving around again:p

dgavin
2012-Feb-09, 07:24 PM
Late updates: On Sat Feb 4th there was an additional 4.8 Mag. quake near the 5.7 area. and a 3.0 quake near the 4.3 one on the pacific plate side of the Jaun De Fuca ridge. 6 Quakes total.

dgavin
2012-Feb-10, 11:27 PM
Another quake reported late, on feb 7th, magnitude 3.4 directly on a part of the rift area, this one half way between the 4.3 and 3.0 from saturdays quakes.

And yesterday another 3.0 at the southmost part of the Jaun de Fuca rift off california coast, this one only at a depth of 600m (has not been reviewed yet though). Considering it's depth, this might be related to a hydrate release. It had a very -short- duration, 22 seconds, and there was no precursor P wave identifiabale (the webicorders may not be sensitive enough to see that though)

8 quakes total now.

dgavin
2012-Feb-11, 05:06 AM
Another 3.0 just posted from jan 9th, near the other one and close to the same time. This one appears to be a normal strike/slip along the rift. 9 total now, still counting.

dgavin
2012-Feb-16, 12:01 AM
Last night, 7:30 PST Valentines quake coming in at a 6.0 mag along the Jaun de Fuca Ridge.

dgavin
2012-Feb-16, 04:40 PM
USGS posted five more older events from Jaun de Fuca, a 4.5 and 4.2 up by Canada, two 3.0’s at the southern edge, and a 2.5 just off shore from Lincoln City, OR.

Count for this week now at 6 quakes, with one strong.
Last two weeks total now upto 15 quakes.

At this point this is just slightly higher then the average amount of activty on Jaun de Fuca, but it's not anything significant to worry about.

Sticks
2012-Feb-16, 05:35 PM
Name of thread changed to Jaun de Fuca Plate Activity

dgavin
2012-Feb-16, 08:03 PM
Thanks Sticks!

Another 2.1 today about 80km from Depot Bay near the subduction region itself.

Gillianren
2012-Feb-16, 08:07 PM
So we've introduced a misspelling into the thread title? It's Juan. Not "Jaun." It's the Spanish for "John."

Swift
2012-Feb-16, 08:30 PM
So we've introduced a misspelling into the thread title? It's Juan. Not "Jaun." It's the Spanish for "John."
:eek:

Everyone clap hard and think of their happy spelling thoughts....http://oi39.tinypic.com/o6h3r7.jpg

Trebuchet
2012-Feb-17, 05:35 PM
So we've introduced a misspelling into the thread title? It's Juan. Not "Jaun." It's the Spanish for "John."

As long as it didn't become "San Juan de Fuca", which is all too common, I'm happy.

Gillianren
2012-Feb-17, 07:00 PM
Right. Two different guys. (Actually, there are a lot of San Juans. But you know what I mean.) Though the Wikipedia page on Juan de Fuca is more interesting than I would have expected.

dgavin
2012-Feb-17, 08:33 PM
Two Aftershocks from the 6.0 added to USGS from prior days activity, a 2.1 and a 2.7. Weekly Count up to 9 again.

The reason these are sometimes delayed, is the Juan de Fuca plate seismographs are not on the list of stations that automatically post events. I asked a local Geologist that works for our Trasportation Dept. here about the delay on these.

So the smaller the event, the more delay there is before a Seismologist gets to it.

dgavin
2012-Feb-22, 07:41 PM
Updates to last weeks activity: Another 4.7 near canada coast, and a 3.1 southern mid-plate.
Two week total: 18 with 1 mag 6.0

This week so far:
3.0 magnitude along subduction area off N. California, 3.4 aftershoock in the region of the prior weeks 6.0.

dgavin
2012-Feb-27, 07:48 PM
A small quake yesterday, 2.7 off the southern oregon coast.

Total events at 21 so far, with an appearent slowing trend last week.

dgavin
2012-Mar-02, 07:31 PM
Two small quakes today, 2.7 and a 2.8 west of Newport in the subduction region.

dgavin
2012-Mar-12, 06:37 PM
No additiona quakes list week, other then the noted 2.

A 3.1 EQ this moring just off the coast west of Newport. Same region as last weeks events.

dgavin
2012-Mar-13, 06:56 PM
A 4.1 EQ 2am this morning on the southern area of the Rift Zone, it Doesn't appear to be volcanic.

dgavin
2012-Mar-20, 11:13 PM
This moring starting just after 1:30am PDT, a micro-swarm of Earthquakes occured on Jaun De Fuca plate along the Subduction region just off the coast of Newport Oregon. Quake's registered in at 3.2, 3.7, then 3.1, at about 30km depth, then the swarm immediately stoped.

I can't really say what this is, as I haven't seen such a small number of quakes in a swarm before, with magnitudes over 1.8. This swarm is around the estimated depth of the Jaun-der-Fuca/Pacific junction area however, so I suspect these were not Strike/Slip quakes, but Lateral/Slip quakes. No movement solutions were posted for them yet, so thats only a guess.

Trebuchet
2012-Mar-21, 12:52 AM
As long as they don't send a major tsunami up the actual Strait of Juan de Fuca, I'm good with that. I spend way too much time looking out at it and wouldn't want any unpleasantries.

dgavin
2012-Mar-26, 06:44 PM
Another 1.9 over the weekend, and just a few (11:04am PDT) minutes ago, an unspecified Mag quake that showed on almost all Oregon siemographs, with Reedssport being the closest one to the quake. This isn't even posted to the auto events yet. Soon as i find out mroe i'll post a followup.

dgavin
2012-Mar-26, 06:50 PM
And just a few (11:04am PDT) minutes ago, an unspecified Mag quake that showed on almost all Oregon siemographs, with Reedssport being the closest one to the quake. This isn't even posted to the auto events yet. Soon as i find out mroe i'll post a followup.

It was a preliminary 6.0 quake 500 miles offshore of Acapulco, Mexico, on the Pacific Rift, 9.9 km deep. Scratch this one of the Jaun-de-Fuca list:)

dgavin
2012-Mar-28, 07:13 PM
Not to be left out, the was a 4.4 mag quake last night on the Juan De Fuca ridge, due west of Coos Bay Oregon.

Gillianren
2012-Mar-28, 07:25 PM
Juan. And Coos Bay.

dgavin
2012-Mar-29, 07:12 PM
2 aftershocks so far from the 4.4 event, both registering 2.1 magnitude.

dgavin
2012-Apr-12, 12:29 AM
There was a 5.9 Quake along the Juan-de-Fuca Ridge (Slip) area, off the Oregon coast, west of Brandon, OR, about 2 hours ago.

This puts the amount of strong quakes at 1 over the normal yearly average. I have no additional comments yet on that little fact.

Trebuchet
2012-Apr-12, 01:13 AM
I think that would be Bandon (http://en.wikipedia.org/wiki/Bandon,_Or), not Brandon. Home of one of my favorite little lighthouses (http://en.wikipedia.org/wiki/Coquille_River_Light). Which I see they've at least partially painted since we were there.

dgavin
2012-Apr-17, 06:59 PM
So far 3 aftershocks to the 5.9 Quake, off the coast of Bandon Oregon, last weeks aftershocks were 2.6 and 2.8. This mornings was a 3.4.

dgavin
2012-Apr-18, 06:11 PM
2 More quakes since yesterdays report. Both along the subduction region this time, a 4.1 Mag near Eureka, CA and a 2.8 Mag near Newport, OR.

dgavin
2012-Apr-23, 07:01 PM
4.1 Mag Yesterday near northern edge offshore of Canada

dgavin
2012-Apr-27, 07:24 PM
Busy week for Juan de Fuca plate.

The 4.1 in prior post the offshore Canada quake was updated to a 4.4, and there were 3 subsequent evens in same region, 3.9, 4.0 and 4.4 magnitudes.

At the otherside of the plate off shore of California, there was a 2.5, 3.0 and a 3.8 mag.

dgavin
2012-May-02, 06:27 PM
So far since last report

2 more quakes off shore of Canada, in same region as others, a 4.5 mag and a 4.0 Mag.

Off shore of california another 3.8 mag quake.

dgavin
2012-Jul-26, 06:37 PM
After quite some time of quietness, there have been four events this week. A 5.1 and a 5.2 earthquake along the southern plate edge, off of california's coast, and a 4.1 and a 4.2 in the mid plate slip flault zone, off the oregon coast.

dgavin
2012-Aug-02, 07:10 PM
Starting on the 29th, there has been what now qualifies as a small earthquake swarm, on the subduction region about 20-30km off shore of Gold Beach, Oregon

2.9 34km SW of Gold Beach, Oregon 2012-08-02 00:00:44 42.204N 124.746W 21.9
2.6 29km SW of Gold Beach, Oregon 2012-08-01 10:59:38 42.235N 124.693W 0.0
2.8 31km SW of Gold Beach, Oregon 2012-08-01 07:15:17 42.228N 124.718W 4.8
2.2 29km SW of Gold Beach, Oregon 2012-08-01 04:30:45 42.210N 124.665W 0.0
2.1 26km SW of Gold Beach, Oregon 2012-08-01 03:03:05 42.223N 124.627W 0.1
1.9 28km SW of Gold Beach, Oregon 2012-08-01 02:15:17 42.196N 124.627W 18.3
2.2 26km SW of Gold Beach, Oregon 2012-08-01 01:00:50 42.241N 124.649W 0.0
2.5 27km SW of Gold Beach, Oregon 2012-08-01 00:34:29 42.238N 124.670W 0.0
3.0 30km SW of Gold Beach, Oregon 2012-07-31 23:53:11 42.220N 124.687W 21.9
2.1 27km SW of Gold Beach, Oregon 2012-07-31 09:13:10 42.234N 124.653W 0.0
1.6 25km SW of Gold Beach, Oregon 2012-07-30 11:47:42 42.236N 124.629W 0.0
1.6 24km SW of Gold Beach, Oregon 2012-07-29 14:35:59 42.249N 124.620W 0.1
1.6 23km SW of Gold Beach, Oregon 2012-07-29 11:34:08 42.257N 124.618W 0.0
2.1 26km SW of Gold Beach, Oregon 2012-07-29 09:30:48 42.239N 124.654W 0.0

dgavin
2012-Aug-09, 07:02 PM
This week three quakes so far, a 4.3 mag in the same location as the swarm two weeks ago. Plus a 4.5 and a 4.9 along the midplate-slip zone of the Jaun-de-Fuca rift area.

dgavin
2012-Aug-22, 07:21 PM
Moderate Quake, plus two aftershocks on the 19th. A 5.5 Mag just off northern most washingtons coast. Followed by a 3.1 and then a 4.2 aftershook.

dgavin
2012-Aug-23, 06:56 PM
Another aftershock this morning, 4.1 magnitude. All four events so far this week have been at 10km depth.

dgavin
2012-Sep-26, 07:20 PM
Moving to a monthly report on this thread. 36 Jaun de Fuca/Cacadia Subduction Earthquakes this last month, three of them coming in at the 4.1 -4.5 magnitude range.

Ara Pacis
2012-Sep-26, 09:20 PM
A question: I'm curious to know if any geologists have used strata along the shores or bathymetry to determine the angle of the NA plate in relation to the subducting plate to get an idea of how stressed it might be and how close it may be to snapping back.

grapes
2012-Sep-26, 11:44 PM
A question: I'm curious to know if any geologists have used strata along the shores or bathymetry to determine the angle of the NA plate in relation to the subducting plate to get an idea of how stressed it might be and how close it may be to snapping back.The earthquakes themselves can pretty much map that out, way deeper than bathymetry or strata, and more accurately--however not good enough to make any sort of stress calculations or timing predictions, which are mostly based on historical data, IIANACI.

Ara Pacis
2012-Oct-01, 08:41 AM
The earthquakes themselves can pretty much map that out, way deeper than bathymetry or strata, and more accurately--however not good enough to make any sort of stress calculations or timing predictions, which are mostly based on historical data, IIANACI.

I'm not sure I follow, nor do I know what IIANACI means. I'm referring to bending stress. When the Japanese earthquake happened last year, parts of Sendai alongthe coast subsided and were inundated (before the tsunami hit), while the portion of plate near the subduction fault snapped upwards. So, it's like a portion of the crust did a seesaw motion along some pivot line. I was wondering if we have historical data that we can look at angle that the crust is deforming and how close that angle is to historical maxima which is relaxed via an earthquake.

dgavin
2012-Oct-02, 06:50 PM
Ara,

Yes there has been investigation in the strata along the NW coast lines, indicating about a once per 700 year time frame for cosatal inudation due to subsidence after a likely megathrust EQ event.

This is what led to the seperate thread I made, about a major Oregon EQ actualy being predicted over the next few decades.

The native american legends about a mythical "Thunderbird", are now thought to be related to stories about these huge plate altering earthquake events. The times of these legends that are datable, seem to roughly coincide with the strata evidence of the megathrust events.

From the Strata evidence, there are some low lying area's along the coast that would likely be underwater after such an event. This may possibly include most of Pacific City and Beverly Beach state park, along with parts of Astoria, Lincoln City, Newport, Coos Bay, and Depot Bay.

Ara Pacis
2012-Oct-03, 05:13 AM
Ara,

Yes there has been investigation in the strata along the NW coast lines, indicating about a once per 700 year time frame for cosatal inudation due to subsidence after a likely megathrust EQ event.

This is what led to the seperate thread I made, about a major Oregon EQ actualy being predicted over the next few decades.

The native american legends about a mythical "Thunderbird", are now thought to be related to stories about these huge plate altering earthquake events. The times of these legends that are datable, seem to roughly coincide with the strata evidence of the megathrust events.

From the Strata evidence, there are some low lying area's along the coast that would likely be underwater after such an event. This may possibly include most of Pacific City and Beverly Beach state park, along with parts of Astoria, Lincoln City, Newport, Coos Bay, and Depot Bay.

Right, but is that only related to periodicity or to an angular deviation from zero level?

dgavin
2012-Oct-03, 02:19 PM
The strata evidence all seems to point to the periodicity of megathrust or larger quakes. Andd there seems to be some variences in how often.

The follow URL repost from another thread, I think will answer some of your questions about strata evidence and quakes.

http://www.pnsn.org/outreach/earthquakesources/CSZ/turbiditeevidence

Ara Pacis
2012-Oct-08, 08:26 AM
The strata evidence all seems to point to the periodicity of megathrust or larger quakes. Andd there seems to be some variences in how often.

The follow URL repost from another thread, I think will answer some of your questions about strata evidence and quakes.

http://www.pnsn.org/outreach/earthquakesources/CSZ/turbiditeevidence

Nope. It doesn't even touch on tilt.

dgavin
2012-Nov-07, 07:56 PM
Catching up here.

On October 28th a Large 7.8 Mag just north of the Juan De Fuca edge. Listing all events upto today.

M Location UTC Lat Lon D-km
4.1 165km SSW of Masset, Canada 2012-11-07 15:04:23 52.649N 133.085W 10.0
4.0 158km SSW of Masset, Canada 2012-11-06 15:47:13 52.717N 133.062W 10.0
4.6 194km SSE of Masset, Canada 2012-11-06 10:27:03 52.335N 131.305W 10.2
4.6 167km S of Masset, Canada 2012-11-04 18:27:19 52.522N 132.346W 20.3
4.9 186km S of Masset, Canada 2012-11-04 12:27:36 52.339N 132.031W 10.4
4.1 142km S of Masset, Canada 2012-11-04 07:42:15 52.741N 131.859W 10.0
4.0 156km S of Masset, Canada 2012-11-04 05:07:53 52.617N 131.957W 10.0
4.2 165km S of Masset, Canada 2012-11-03 17:49:14 52.535N 132.007W 22.4
4.0 187km SSW of Masset, Canada 2012-11-03 12:18:42 52.380N 132.751W 9.8
4.0 157km S of Masset, Canada 2012-11-03 09:48:24 52.611N 132.378W 10.1
4.4 166km S of Masset, Canada 2012-11-03 04:25:19 52.522N 131.870W 12.8
4.0 203km S of Masset, Canada 2012-11-02 08:37:10 52.186N 132.160W 10.4
4.5 182km S of Masset, Canada 2012-11-02 08:19:59 52.379N 132.025W 10.2
4.2 170km S of Masset, Canada 2012-11-02 07:15:45 52.497N 131.759W 11.0
4.9 161km S of Masset, Canada 2012-11-01 03:16:00 52.564N 131.943W 10.3
5.1 181km SSE of Masset, Canada 2012-11-01 03:15:23 52.500N 131.100W 1.0
4.0 165km S of Masset, Canada 2012-10-30 17:33:29 52.535N 132.323W 1.8
4.6 192km S of Masset, Canada 2012-10-30 14:10:59 52.285N 131.948W 10.0
4.7 208km S of Masset, Canada 2012-10-30 04:40:15 52.170N 131.604W 10.2
5.0 199km S of Masset, Canada 2012-10-30 02:55:08 52.222N 132.116W 19.2
6.2 210km S of Masset, Canada 2012-10-30 02:48:58 52.129N 132.320W 18.6
4.1 179km S of Masset, Canada 2012-10-30 00:35:09 52.423N 131.655W 10.0
4.0 166km S of Masset, Canada 2012-10-30 00:32:18 52.526N 131.936W 10.0
4.3 158km S of Masset, Canada 2012-10-29 22:00:33 52.593N 132.273W 10.0
4.6 188km SSE of Masset, Canada 2012-10-29 20:49:49 52.366N 131.459W 26.5
4.1 198km S of Masset, Canada 2012-10-29 16:33:08 52.231N 131.971W 10.0
4.0 216km S of Masset, Canada 2012-10-29 15:38:29 52.074N 132.137W 10.0
4.0 225km S of Masset, Canada 2012-10-29 15:15:02 51.989N 132.225W 10.0
4.0 224km S of Masset, Canada 2012-10-29 15:01:06 52.013N 131.757W 10.0
4.4 163km S of Masset, Canada 2012-10-29 12:05:14 52.574N 132.552W 10.2
4.1 119km S of Masset, Canada 2012-10-29 06:03:52 52.959N 132.377W 3.3
4.1 173km S of Masset, Canada 2012-10-29 03:47:55 52.461N 132.190W 10.0
4.0 182km S of Masset, Canada 2012-10-29 02:40:53 52.396N 132.502W 10.0
4.6 165km S of Masset, Canada 2012-10-29 01:49:02 52.530N 131.965W 10.0
4.3 184km S of Masset, Canada 2012-10-29 00:26:49 52.358N 132.096W 10.0
4.0 174km SSE of Masset, Canada 2012-10-29 00:18:50 52.612N 130.948W 10.0
4.1 126km SSE of Masset, Canada 2012-10-28 23:55:02 52.978N 131.333W 10.0
4.7 161km S of Masset, Canada 2012-10-28 23:34:23 52.570N 132.291W 10.0
4.9 144km S of Masset, Canada 2012-10-28 23:26:50 52.733N 132.436W 10.0
4.2 158km S of Masset, Canada 2012-10-28 23:11:17 52.608N 132.454W 12.5
4.7 189km S of Masset, Canada 2012-10-28 22:41:28 52.316N 131.904W 10.0
4.6 158km S of Masset, Canada 2012-10-28 21:38:19 52.602N 131.893W 24.7
5.1 166km S of Masset, Canada 2012-10-28 19:16:55 52.544N 132.580W 47.2
5.5 190km S of Masset, Canada 2012-10-28 19:09:56 52.315N 131.860W 14.8
5.4 151km SSW of Masset, Canada 2012-10-28 19:03:24 52.742N 132.902W 32.8
6.3 177km SSW of Masset, Canada 2012-10-28 18:54:16 52.480N 132.793W 20.0
4.3 169km SSE of Masset, Canada 2012-10-28 16:17:03 52.537N 131.508W 10.0
4.6 140km SSW of Masset, Canada 2012-10-28 15:59:11 52.786N 132.595W 10.0
4.4 161km SSW of Masset, Canada 2012-10-28 15:57:15 52.638N 132.866W 10.7
4.4 177km S of Masset, Canada 2012-10-28 15:48:45 52.427N 132.261W 10.0
4.4 191km S of Masset, Canada 2012-10-28 15:44:59 52.309N 132.408W 10.0
4.0 185km SSE of Masset, Canada 2012-10-28 15:42:21 52.404N 131.422W 10.0
4.3 135km S of Masset, Canada 2012-10-28 15:24:22 52.803N 132.113W 10.0
4.0 166km S of Masset, Canada 2012-10-28 15:10:34 52.516N 132.066W 10.0
4.4 178km S of Masset, Canada 2012-10-28 15:06:55 52.417N 132.169W 10.0
4.0 164km SSE of Masset, Canada 2012-10-28 14:14:28 52.588N 131.440W 7.7
4.2 154km S of Masset, Canada 2012-10-28 14:04:27 52.635N 132.403W 10.0
4.1 190km SW of Bella Bella Islands, Canada 2012-10-28 13:45:48 51.127N 130.305W 10.0
4.8 175km S of Masset, Canada 2012-10-28 13:09:14 52.445N 131.842W 10.0
4.1 127km S of Masset, Canada 2012-10-28 12:38:46 52.870N 132.204W 10.1
4.0 142km S of Masset, Canada 2012-10-28 12:18:00 52.750N 131.769W 10.0
4.1 161km S of Masset, Canada 2012-10-28 12:09:43 52.568N 132.065W 10.0
4.7 175km S of Masset, Canada 2012-10-28 11:53:21 52.438N 132.201W 10.5
4.8 180km S of Masset, Canada 2012-10-28 11:27:46 52.395N 132.161W 11.1
4.3 183km SSE of Masset, Canada 2012-10-28 11:17:22 52.400N 131.566W 10.6
4.0 172km S of Masset, Canada 2012-10-28 10:59:14 52.477N 131.769W 9.7
4.3 170km S of Masset, Canada 2012-10-28 10:50:32 52.484N 131.945W 10.3
4.7 157km S of Masset, Canada 2012-10-28 10:45:50 52.621N 132.500W 10.2
4.5 145km SSW of Masset, Canada 2012-10-28 10:23:09 52.753N 132.678W 10.2
4.3 171km S of Masset, Canada 2012-10-28 10:10:27 52.482N 132.247W 10.3
4.3 119km S of Masset, Canada 2012-10-28 10:04:37 52.948N 132.285W 10.0
4.1 127km S of Masset, Canada 2012-10-28 09:52:58 52.892N 131.733W 10.0
4.4 127km S of Masset, Canada 2012-10-28 09:45:39 52.886N 132.392W 10.2
4.4 221km S of Masset, Canada 2012-10-28 09:41:16 52.029N 132.187W 10.0
4.6 196km S of Masset, Canada 2012-10-28 09:36:36 52.258N 132.343W 10.3
4.4 173km SSE of Masset, Canada 2012-10-28 09:22:50 52.551N 131.193W 10.0
5.1 197km S of Masset, Canada 2012-10-28 09:17:27 52.243N 131.996W 10.0
4.2 215km S of Masset, Canada 2012-10-28 09:15:48 52.102N 131.653W 10.0
4.2 277km SSW of Masset, Canada 2012-10-28 08:47:38 51.634N 133.314W 10.0
4.3 216km S of Masset, Canada 2012-10-28 08:22:04 52.067N 132.073W 10.0
5.0 198km SSE of Masset, Canada 2012-10-28 07:25:22 52.270N 131.493W 10.6
4.9 140km S of Masset, Canada 2012-10-28 07:16:37 52.775N 132.456W 11.4
4.6 212km S of Masset, Canada 2012-10-28 07:12:14 52.109N 132.221W 10.0
4.4 231km S of Masset, Canada 2012-10-28 07:02:19 51.941N 131.836W 10.8
5.0 203km SSE of Masset, Canada 2012-10-28 06:16:53 52.268N 131.212W 11.5
4.5 139km SSW of Masset, Canada 2012-10-28 05:51:17 52.815N 132.714W 10.3
4.3 181km SSE of Masset, Canada 2012-10-28 05:47:08 52.430N 131.451W 10.1
4.1 248km S of Masset, Canada 2012-10-28 05:38:38 51.786N 132.312W 10.1
4.3 211km S of Masset, Canada 2012-10-28 05:21:36 52.140N 131.571W 10.0
4.3 169km S of Masset, Canada 2012-10-28 05:15:12 52.499N 132.222W 10.1
4.5 178km S of Masset, Canada 2012-10-28 05:02:49 52.409N 132.165W 10.3
4.3 180km S of Masset, Canada 2012-10-28 04:54:46 52.403N 132.439W 10.1
4.7 155km SSW of Masset, Canada 2012-10-28 04:41:05 52.648N 132.597W 20.0
4.6 140km SSW of Masset, Canada 2012-10-28 04:33:51 52.906N 133.120W 10.0
5.1 254km SSW of Masset, Canada 2012-10-28 04:25:17 51.930N 133.642W 20.0
4.8 183km S of Masset, Canada 2012-10-28 03:52:25 52.372N 131.823W 20.0
5.8 154km S of Masset, Canada 2012-10-28 03:14:10 52.629N 132.243W 10.0
7.8 141km S of Masset, Canada 2012-10-28 03:04:09 52.742N 132.131W 20.1

dgavin
2012-Nov-07, 08:08 PM
Another large event, this time on the Cocos Subduction region, Posting this here as the Cocos Plate and Juan de Fuca plate were once the same plate (Fallon Plate) and likey once were part of the same subduction zone.
M Location UTC Lat Lon Dkm
7.4 24km S of Champerico, Guatemala 2012-11-07 16:35:50 14.083N 91.916W 41.6

According to Reuters


The quake was also felt in El Salvador and more than 750 miles away in Mexico City, where some office workers were also briefly evacuated. Mayor Marcelo Ebrard said the quake was felt strongly in a large part of the city of 20 million people.

dgavin
2012-Nov-08, 03:17 PM
A moderate one, 6.3 mag off vancover island last evening at 6pm

dgavin
2012-Nov-19, 07:49 PM
A Minor quake, 3.2 mag below NW Portland this morning at 6:15 am

dgavin
2013-Feb-06, 08:49 PM
A 6.0 quake about 250km north of the Juan de Fuca plate this week.

The Tsunami warning issued from the 8.0 EQ south of Solamon Is. last night was canceled early this morning. The largest Tsunami wave recorded form that quake was only 1.5 feet (4.4 dm)

dgavin
2014-Jan-21, 07:44 PM
Almost made it a full year without much to report, there was a series of 4 inta-plate earth quakes last week, ranging from a 4.0 in the north edge, to 2.0 to the south edge. The 4 quakes form a line that parrelles the subduction region almost exactly, but are mid plate. I'm assume this is likely some effect of intra-plate compression.

dgavin
2014-Mar-10, 02:01 PM
A 6.9 quake on the Juan de Fuca plate, just 70 miles off shore of northern Calif.



2.9 59km W of Ferndale, California 2014-03-11 01:05:12 UTC-07:001.3 km
3.0 87km WNW of Ferndale, California 2014-03-10 17:13:05 UTC-07:005.0 km
3.7 64km WSW of Ferndale, California 2014-03-10 08:16:29 UTC-07:007.9 km
3.0 76km W of Ferndale, California 2014-03-10 08:00:14 UTC-07:000.1 km
3.0 66km W of Ferndale, California 2014-03-10 07:42:56 UTC-07:001.3 km
3.3 87km W of Ferndale, California 2014-03-10 06:58:39 UTC-07:005.0 km
2.9 65km W of Ferndale, California 2014-03-10 05:41:04 UTC-07:0024.2 km
3.5 88km W of Ferndale, California 2014-03-10 03:46:22 UTC-07:0022.0 km
4.5 85km WNW of Ferndale, California 2014-03-10 03:28:16 UTC-07:005.1 km
3.4 88km WNW of Ferndale, California 2014-03-10 03:18:04 UTC-07:005.0 km
2.5 28km SW of Ferndale, California 2014-03-10 02:57:33 UTC-07:0023.5 km
2.7 28km SW of Rio Dell, California 2014-03-10 02:56:33 UTC-07:0019.3 km
3.7 77km WNW of Ferndale, California 2014-03-10 02:54:26 UTC-07:0021.4 km
3.6 82km WNW of Ferndale, California 2014-03-10 02:42:42 UTC-07:0024.5 km
3.2 73km W of Ferndale, California 2014-03-10 00:49:00 UTC-07:005.1 km
2.6 20km SSW of Rio Dell, California 2014-03-10 00:15:48 UTC-07:004.0 km
2.7 47km W of Ferndale, California 2014-03-09 23:58:47 UTC-07:004.8 km
2.8 53km WNW of Ferndale, California 2014-03-09 23:39:09 UTC-07:000.4 km
2.6 76km W of Ferndale, California 2014-03-09 23:30:03 UTC-07:0011.2 km
3.3 59km WNW of Ferndale, California 2014-03-09 23:22:45 UTC-07:003.5 km
3.2 93km W of Ferndale, California 2014-03-09 23:21:15 UTC-07:0010.0 km
2.6 90km W of Ferndale, California 2014-03-09 23:13:07 UTC-07:0018.0 km
2.8 83km WNW of Ferndale, California 2014-03-09 23:12:23 UTC-07:0024.3 km
2.8 73km WNW of Ferndale, California 2014-03-09 22:57:30 UTC-07:0022.1 km
4.4 76km W of Ferndale, California 2014-03-09 22:51:10 UTC-07:0018.8 km
2.9 72km W of Ferndale, California 2014-03-09 22:43:26 UTC-07:001.5 km
3.0 82km WNW of Ferndale, California 2014-03-09 22:41:47 UTC-07:0024.6 km
3.8 140km W of Ferndale, California 2014-03-09 22:36:39 UTC-07:0017.3 km
3.4 96km W of Ferndale, California 2014-03-09 22:32:14 UTC-07:0010.7 km
6.8 77km WNW of Ferndale, California 2014-03-09 22:18:13 UTC-07:0016.6 km
3.3 83km WNW of Ferndale, California 2014-03-09 22:04:09 UTC-07:005.0 km
2.7 36km ENE of Redway, California 2014-03-09 21:17:53 UTC-07:0033.0 km
1.9 4km E of Fortuna, California 2014-03-09 18:17:20 UTC-07:0017.3 km
2.6 4km N of Hydesville, California 2014-03-09 12:13:45 UTC-07:0017.3 km

dgavin
2014-Mar-11, 04:18 AM
Seismograph link (Courtesy of PNSN) of the 6.8 from Dodson Butte in Oregon. This link will only be good for a few weeks. http://pnsn.org/seismogram/2014/3/10/dbo/bhz/uo/

dgavin
2014-May-17, 02:09 PM
A 5.1, 5.3, and 4.1 earthquake along the fracture/slip zone west of coos bay offshore on the 12th.

Trebuchet
2014-May-19, 04:31 PM
Things that bug me: Every time you update this thread, if I'm at the vacation house, I have to look out the window to see if the Strait of Juan de Fuca is still there. It is!

dgavin
2014-May-20, 01:12 PM
But is it still....strait?! lol

Trebuchet
2014-May-20, 02:12 PM
But is it still....strait?! lol

More or less. At least the wind can blow strait down it! I used to tell people that other than the Dungeness Spit (max elevation about 10 feet), the next land in that direction was Japan. (It actually turns out to be Taiwan.) Nothing to stop the wind. Only thing I don't like about the place.