6.9 Quake Just Slammed California

There are several hundred recorded eatquake worldwide per day, especially aroun d the Ring Of Fire that touches the CA / coast. That this geological super-sub-system blew off some 'steam' over there tonight, out in the vast expanse, rather than a couple hundreds miles to the East, thats good news. No need for alarm. A good night for millions.

MrInquisitive
There are earthquakes of this magnitude or larger in this region all the time -- a couple a year, often times. Take a look at the USGS EQ catalog for the area. Don't know why this made the news, and don't know why people are talking about here. There's at least two threads on it here, for Pete's sake.

edit on 10-3-2014 by MrInquisitive because: (no reason given)

There are not quakes of this magnnitude in that region "all the time" and certainly not "a couple a year, often times". Maybe you should take a look at the USGS database before you post such generalizations -- because it appears that you haven't.

That quake occurred at 40.829°N 125.134°W. I just did a search of the USGS/NEIC database for all quakes within 320km (circa 200 miles) of 40.8 N and 125 W, magnitude 6.0 or greater, since 1/1/2000 and until today. There were precisely four:

6.9 77km WNW of Ferndale, California 2014-03-10 06:18:13 UTC+01:00 16.6 km
6.5 offshore Northern California 2010-01-10 01:27:39 UTC+01:00 29.3 km
6.6 off the coast of Northern California 2005-06-17 07:21:42 UTC+01:00 13.2 km
7.2 off the coast of Northern California 2005-06-15 03:50:53 UTC+01:00 9.9 km

[Anyone can check the above results in the database by using their search facility here and inputting the same coordinates, search region, time frame and quake range. (The 6.0 is ually set as default anyway.) ]

So, besides this one, there was one over mag six in 2010 and two in 2005 (within days of each other).

That's all. Three others over mag 6.0 in more than fourteen years, prior to today.

This is not a common event and hence the concerns expressed by some people are fully justified. Your "nothing to see here, move along" kind of attitude is frankly rather out of place.

Mike

reply to post by JustMike


How many major quakes inland since / during that stretch? Perhaps the hot-metric-zone has shifted out towards sea?

Aftershocks continuing

Magnitude: 3.4
Location: California, 88 km WNW of Ferndale

Time: Mon, Mar 10, 2014, 3:18:04 AM PDT
GMT: Mon, Mar 10, 2014 10:18:04 GMT

Latitude: 40° 44' 40" N (40.7447°)
Longitude: 125° 17' 19" W (-125.2887°)
Depth: 5.0 km

Map: maps.google.com...@40.744700,-125.288700&z=6

More Information (while available): earthquake.usgs.gov...

Data provided by US Geological Survey.

reply to post by violet


Hey, thanks for that!! update. I clicked your map and got Florida!! hahahah! ..But, that's ok

IgnoranceIsntBlisss
reply to post by JustMike

 

How many major quakes inland since / during that stretch? Perhaps the hot-metric-zone has shifted out towards sea?

They've all been off shore on the Juan du Fuca plate I believe
The last one I posted is much closer to the mainland on another plate .

Well I don't want to alarm anyone, but one thing I have noticed when I pulled again a 30 day 2.5+ for this area, is that there have been 7 quakes now, directly on or very near the exact fault thought responsible for the last massive ~9M quake there, some 300 years ago. This fault is called the Cascadia Megathrust, and I show it here in this pic, directly left of the label. That is the fault that runs some 1000 km up the west coast, and the bringer of monsters. (Another aftershock incoming, estimate: 4.2 or so as I type this).



It is possible that the surface tension is breaking, in preparation for another slammer. No one knows the exact precursory seismicity, if any, to another massive quake there. We can only watch and wait.

EDIT: that aftershock was a 4.4- I am conservative anymore


EDIT2: And yeah, I see the one that just happened south of there, out at sea. Before I freak out though cause now we have seismicity on all sides of the zone- I am going to wait for a while and see if they move that quake. It has happened many times before. They move quakes all the time out there- cause locating them precisely there is rough.

Aftershocks back up to mag 4

Magnitude: 4.5
Location: California, 120 km SW of Ferndale

Time: Mon, Mar 10, 2014, 3:28:06 AM PDT
GMT: Mon, Mar 10, 2014 10:28:06 GMT

Latitude: 39° 48' 46" N (39.8130°)
Longitude: 125° 16' 26" W (-125.2740°)
Depth: 13.0 km

Map: maps.google.com...@39.813000,-125.274000&z=6

More Information (while available): earthquake.usgs.gov...

Data provided by US Geological Survey.


---------------



Magnitude: 4.4
Location: California, 85 km WNW of Ferndale

Time: Mon, Mar 10, 2014, 3:28:16 AM PDT
GMT: Mon, Mar 10, 2014 10:28:16 GMT

Latitude: 40° 45' 28" N (40.7578°)
Longitude: 125° 14' 30" W (-125.2418°)
Depth: 5.1 km

Map: maps.google.com...@40.757800,-125.241800&z=6

More Information (while available): earthquake.usgs.gov...

Data provided by US Geological Survey.

TA, I'm having a heck of a time hunting down a nearby station to monitor through GEE (most in the area seem to be offline) Whatever network you are using to watch, is it by chance available in the Add Network list in GEE??

TrueAmerican
EDIT2: And yeah, I see the one that just happened south of there, out at sea. Before I freak out though cause now we have seismicity on all sides of the zone- I am going to wait for a while and see if they move that quake. It has happened many times before. They move quakes all the time out there- cause locating them precisely there is rough.

edit on Mon Mar 10th 2014 by TrueAmerican because: (no reason given)

Touche. It's gone, just as I suspected! HA! Ok, no need to freak out anymore. No, it's not some USGS conspiracy. As I said, they have trouble there with the autolocator. This time experience paid.

Nyiah
TA, I'm having a heck of a time hunting down a nearby station to monitor through GEE (most in the area seem to be offline) Whatever network you are using to watch, is it by chance available in the Add Network list in GEE??

There might be closer stations, but currently two of the stations I am using, that I know you can access in GEE are on the TA network- so add that network, and look for stations:
N02D and
M02C

Here you all cone again with the doom. Every event lately is the end of the world WWIII California into the sea, the aliens are coming Jesus is coming. Why. Why is everyone so eager to die or see others die ? I just don't get it. Can't we just report an earthquake without it being the end or the big one ?

TrueAmerican
There might be closer stations, but currently two of the stations I am using, that I know you can access in GEE are on the TA network- so add that network, and look for stations:
N02D and
M02C

Oh thanks! Since they updated GEE, it's hit or miss on the icons as to whether or not the station's actually available. Didn't they used to have color indications of that? Anyway, now that I've found those you pointed out, time to sit back & watch 'em

reply to post by TrueAmerican

Agreed, those are the closest working stations in GEE--no other networks have been loading since the latest release.

This PBO station is the nearest to these earthquakes. PB. 046. EHZ.

It figures, I go to sleep early because of the time change, and the quake I have been anticipating (because of GPS changes similar to conditions pre-June 2005) for the past 4 months comes to pass...

TrueAmerican
Sorry, west, can't help ya with that. IRIS has been pretty crappy lately as far as live monitoring.

So far, this appears to be a classic mainshock-aftershock sequence. No real big aftershocks yet to make me suspect the worst. But I remind you that's what we thought about the 9+ in Japan after the 7.2 hit. It looked just the same, with its own set of aftershocks. Then WHAM.

Let's make sure to keep that fear factor tuned up now.

AutumnWitch657

TrueAmerican
Sorry, west, can't help ya with that. IRIS has been pretty crappy lately as far as live monitoring.

So far, this appears to be a classic mainshock-aftershock sequence. No real big aftershocks yet to make me suspect the worst. But I remind you that's what we thought about the 9+ in Japan after the 7.2 hit. It looked just the same, with its own set of aftershocks. Then WHAM.

Let's make sure to keep that fear factor tuned up now.

Its better to be safe than sorry.....And i rather be safe


As for fear ....its not about fear but info that people need to know.

reply to post by Olivine


Yes, it may be the closest station, but it is a shortband station, along with all the other PB network stations in that cluster on the northern Cali coast. The data was clipped, capping at about 13 e5 counts. We really do better to watch these bigger quakes on broadband stations. And the TA network is good for that. That PB station and the others close to it are great for the smaller aftershocks though. For example, just now there was a smaller one, and it's not even showing up on the TA stations. So good observation, oli.

AutumnWitch657
Let's make sure to keep that fear factor tuned up now.

So do you have anything at all to add constructively to this thread, or are you just going to sit there and whine? Where's mah cheese... I'll even give you some of my favorite... Port WHINE!

Well the northern California network seismogram page is a complete mess. A bit overrun by the mag 6.9. (all of the stations that begin with "K" are near the northern CA coast)



The spectrograms are much more useful.
(Again, the "K" stations are nearest the epicentral region)

reply to post by Olivine


Just curious, why are spectrograms more useful?

reply to post by TrueAmerican


Thanks. Ive been studying this area since I joined ATS. It's my former home, and future (moving back next summer). So I've got my favorite avenues of viewing publically available data. I really wish Berkeley (BK network) and NC network were available in IRIS, but alas, no.

The new PNSN spectrogram page for northern CA tremor has good images, too, but it only updates every hour. The LGB station on this page shows how Mt. Shasta is responding to the seismic waves.