Quake Alaska 7.7 or 7.5 near Juneau

Well, this is interesting. We had an earlier 7.x in B.C., then a littler 6.x near it, now a big ol 7.x north of it in Alaska but still close. That chunk of fault is just being very active.

So first off, h/t to Crosspatch and Sabertoothed who both spotted it (and posted comments in two other threads).

But I do have to wonder if ‘three in a row’ means they are preshocks for something yet to come. IMHO, anyone in Alaska down through Washington / Oregon on the Cascadia needs go to a higher level of alert and preparedness. That much action, in the context of the prior 9 scale events on the other side of the plate in Indonesia (years back) and Japan (not so long back); and given the history of Great Quakes on that fault system (from the 8.6 in Anchorage years back to historic 9 scale events evidenced in the dirt – though with big error bars); well, it’s just not a time to be taking added risks. More like a time to check the “bug out bag” and gas up the car, stock some food and make sure the generator works…

With that, the particulars. I’m going to leave in the ‘static captures’ from the prior quakes so we can see the pattern.

Magnitude 7.5 - SOUTHEASTERN ALASKA

2013 January 05 08:58:16 UTC 

Earthquake Details
This event has been reviewed by a seismologist.Magnitude	7.5
Date-Time	Saturday, January 05, 2013 at 08:58:16 UTC
Friday, January 04, 2013 at 11:58:16 PM at epicenter 
Time of Earthquake in other Time Zones
Location	55.238°N, 134.777°W
Depth	9.9 km (6.2 miles)
Region	SOUTHEASTERN ALASKA
Distances	102 km (63 miles) W of Craig, Alaska
303 km (188 miles) WNW of Prince Rupert, Canada
335 km (208 miles) S of Juneau, Alaska
402 km (249 miles) WNW of Terrace, Canada
Location Uncertainty	horizontal +/- 16.1 km (10.0 miles); depth +/- 5 km (3.1 miles)
Parameters	NST= 17, Nph= 17, Dmin=108 km, Rmss=0.61 sec, Gp=162°,
M-type=(unknown type), Version=8
Source	Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)
Event ID	usc000ejqv

Prior Series

British Columbia has a 7.7 (a while ago…)

Static captures of image:

Quakes 7.7 British Columbia. 28 Oct 2012 230_55

Quakes 7.7 British Columbia. 28 Oct 2012 230_55

British Columbia 6.3

Quake 6.3 BC 8 Nov 2012

Quake 6.3 BC 8 Nov 2012

Alaska originally 7.7, now 7.5

Static:

Quake Alaska 5 Jan 2012 about 7.5

Quake Alaska 5 Jan 2012 about 7.5

Live Close up:

Quakes Alaska near Juneau live map

Quakes Alaska near Juneau live map

Original Image

Global Views

30 Days:

30 Day Global View

30 Day Global View

Recent:

Quakes Last 7 Days Live

Quakes Last 7 Days Live

Northern Hemisphere

North Polar Earthquake Map

North Polar Earthquake Map

Original Image with Clickable Details

North America

Quakes North America Live Map

Quakes North America Live Map

Original Image

Southern Hemisphere

A view of Earthquakes from the South Pole

A view of Earthquakes from the South Pole

Original Image with Clickable Details

Asia and Russia

Asia Quake Map

Asia Quake Map

Original Image with clickable areas

Australia / New Zealand

This is a live map of the Australia / Indonesia / New Zealand area:

Australia / Indonesia / New Zealand Quake Map

Australia / Indonesia / New Zealand Quake Map

Original with clickable regions to zoom in

California Map

Action Closer to Me

As I live in California, it makes it easier for me if I keep them in the list where I can see what’s shaking near me.

Here is an alternative view of things with the fault lines highlighted:

California Quakes with fault lines

California Quakes with fault lines

Original Image

Map of Plates

You can see it is where plates collide here:

Plates Of The World

Plates Of The World

Original Image, and with other language options.

Some Volcano Stuff

The Smithsonian page:

http://www.volcano.si.edu/reports/usgs/

USGS Page listing recent major quakes:

http://earthquake.usgs.gov/earthquakes/eqinthenews/

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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10 Responses to Quake Alaska 7.7 or 7.5 near Juneau

  1. sabretoothed says:

    If its an earthquake swarm, is it going north or south ?
    Will Cascadia be next or will Anchorage be whacked again like in the 60s

    http://www.seattlepi.com/local/article/Will-a-megathrust-earthquake-strike-the-NW-in-4162559.php#photo-3975722

    http://en.wikipedia.org/wiki/1964_Alaska_earthquake

  2. Jeff Alberts says:

    I’m on Whidbey Island ( https://maps.google.com/?ll=48.295528,-122.619095&spn=0.323427,0.567169&t=h&z=11 ) in Puget Sound. My house is at 220 ft elevation, and on the back side of the island (not directly open to the Sound), so i’m not worried about a tsunami directly affecting my house. It WOULD directly affect my ability to get off the island, since the only road leading off would probably be destroyed, as would Whidbey NAS.

    If there is a really bad quake, however, the Deception Pass Bridge, which I take every day to work, and is only one of two ways off the island, could be too damaged to use. The other way off is the Clinton/Mukilteo ferry at the sound end of the island. Even on a good day that’s pretty crowded.

    I’ve got a 10kw Propane Generator that kicks in automatically when grid power is lost. Don’t have a good emergency kit. Will have to do that.

  3. sabretoothed says:

    http://en.trend.az/regions/scaucasus/georgia/2105346.html Something brewing underwater near Italy, was it that giant volcano that lives underwater there?

    http://earthquake-report.com/2013/01/04/volcano-activity-of-january-4-2013/

    January 4, 2013 volcano activity

    Update : another Mammoth Mountain deep earthquake swarm
    Another deep earthquake swarm at Mammoth Mountain volcano (CA). I saw this one developing late last night actually, but larger magnitude (i.e. locatable) earthquakes began earlier today. The intensity of the swarm again is not comparable to the late October 2012 sequence (thus far!), but what is interesting is that this one is focused at a significantly shallower level (~12 km vs.17-20 km for the previous swarms) and is centered directly beneath Mammoth Mountain rather than southwest of the edifice. Dilatometers are also showing offsets in trend with the current swarm, whereas the last deep swarm (28-29 December) did not. The December activity again was at around 20 km depth, was comprised of rather small magnitude earthquakes, and lasted only one day, which probably explains the lack of a clear response by dilatometers near the surface for that unrest. See LV and MRD graphs below

  4. crosspatch says:

    The quakes would have been way different. The quake off the coast of Alaska would have been strike slip motion on a transform fault where the Pacific plate is sliding past the North American plate. The one off of BC would have been on a subduction fault where the Juan de Fuca plate (northern remnant of the old Farallon plate) is subducting under the North American plate. The stress buildup would be different where the two quakes occurred and would likely not be related.

  5. GeoLurking says:

    If I remember correctly, the Queen Charlotte Islands quake (the 7.7) was reverse faulting, typical of a subduction zone, though that area is north of the Explorer microplate and the Cascadia subduction zone. It’s still a convergent margin, but it acts to push up mountains. According to the USGS Google Gizo, it’s a continental convergent margin. The thing about that event that I found cool, was that at least one of the the follow-on quakes showed normal faulting… the two sides moving away from each other. (the opposite of the initial quake).

    As for the more recent one, definitely strike-slip. Using the formulas in Wells-Coppersmith (1994), it works out to about 4.9 meters maximum displacement along the fault (2.7 meters average) The subsurface rupture length would have been about 120 km. (the length of the rupture).

    http://seismo.berkeley.edu/~rallen/teaching/eps256-s07/WellsCoppersmith1994.pdf

  6. E.M.Smith says:

    Wow, California is under 300 count. Odd, we’ve gone ominously quiet…

    @Crosspatch:

    When anything that big lets loose, the stresses redistribute all up and down the faults. Even a great quake on the Japan side is known to correlate with large quakes on the other side of the Pacific (both above and below the triple junction). That the two parts of the system are going in different modes does not decouple the rocks or the energy flows.

    The Hayward / Calaveras and the San Andreas tend to have quakes a few years apart, despite being different fault systems (though both subducting). Stress relieved on one increases stress on the other ( or so it is thought).

    So it’s well worth it to watch any ‘cluster’ or ‘swarm’ and pay attention.

    @Sabertoothed:

    We’re not even sure if it IS a ‘swarm’ yet. So far it’s just normal stress releases.

    Mammoth always has minor swarms from time to time (decade to decade). If there is a consistent ramp up, then it’s a concern.

    Interesting story on the cable. Link says Georgia, though. Need to know where it was to know if it is an unusual thing or not.

    @Jeff Alberts:

    Not hard to ‘make the basics’ of a kit. Especially for a ‘shelter in place’ with the car or a damaged house. First step is to just park the car outside the garage in high concern times and toss some spare blankets / sleeping bag in it. Instant water proof home… with radio and lights too. I ‘rode out’ at 6ish in my car in a parking lot once. It was fun and only a little bit ‘bouncy’. No risk at all, really. Even the 7.2 didn’t hurt any cars in open spaces.

    Add some ‘ready to eat canned food and water’ and you are set for a pretty good time. ( Ravioli from a can are edible cold. I’ve lived on it when on various odd jobs before.)

    For more “prep”, see:

    https://chiefio.wordpress.com/2009/05/27/crisis-kits-and-preparedness-packs/

    Biggest issue is likely to be water. I have some “surplus” food grade drums filled with water in the back yard. I think they cost me something like $20 each. A cheap ‘kids wading pool’ can be set up and filled as a stop gap. More than you need for a week for about $10.

    Easy DIY food storage:

    https://chiefio.wordpress.com/2009/04/06/food-storage-systems/

    came through a 7.2 (hey, that’s what they called it when I was in it… only later did they say it was smaller, so I’m going to continue to claim I got my 7.x badge! ;-) ok.

    For a stop gap, just get a week or two worth of ‘canned goods’. They can be eaten cold and you don’t need to cook to rehydrate them like dried goods. Ravioli, SPAM, peas, green beans, tuna, etc. ( I’d not eat corn without re-cooking it as it has more botulism risk). Add crackers and some single serve mayo packets from the local fast food place to the tuna and you are ‘good to go’ for a while ;-) A large dry salami and a brick of cheese holds up well too. (It ought to be ‘refrigerator temps’ up there about now… so string cheese ought to keep well. If not, get jerky… unless there are bears on your island… )

    Warmth, water, physical shelter; then all the other stuff including food. The car (full tank!) gives you two of the first three. Add a good sleeping bag and coat to reduce fuel burn staying warm in the car… pick up a flat of water bottles at the mega-mart on the way back from work tomorrow for the water.

    Cheap ($20 ish) and easy emergency lighting kit that works in the car too and saves battery drain:

    https://chiefio.wordpress.com/2011/02/17/minimalist-emergency-power/

    You can substitute an LED light if desired. Also, a Maglight with LED bulb runs for something like a couple of hundred hours on a set of batteries. I always have at least one small flashlight on my person. ( In the computer room with power out post quake it was pitch black. We were using laptops for flashlights… now I have one ‘on my hip’ at all times.)

    Oh, and put a pair of spare heavy boots in the car. You might end up running out in the night barefoot… maybe add a set of clothes too… and pair of work gloves.

  7. John Robertson says:

    My bug-out is a diesel 4×4 with a old 8ft camper on it, great for road trips as well.
    Course I’m up on the canadian shield and relatively safe from earthquake.Forest fires the #1 fear here.
    Was trying to remember where on the old coast road in N California or Oregon state the road has dropped 2-3ft in a past earthquake and the tear has been patched over.Its quite the lurch.
    Kind of rubs it in, how fragile our infrastructure is.
    If we wanted to get in on the highly lucrative fear-mongerring business, it obvious some kind of majestic subterranean beast is heading north (any direction) and can only be appeased by the payment of indulgences to the correct persons.

    The Italian technician who insisted the earthquake was coming, prior to that which resulted in the court case, was there some mention of a prediction on his part?
    Got to love the LED when I was a kid, a dry cell flashlight was lucky to last an evening. Now those AAA headlamps last for months, freeze-dried meals and other such campers goodies make it easy to be prepared. Course best line on that, was the theory, we always prepare for the wrong emergency, Pournelle&Niven; Footfall.
    But basic preparedness is a state of mind, probably why our parents taught us to love camping.

  8. adolfogiurfa says:

    @John Robertson….Unfortunately those LED flashlights won´t help too much during a finance break down … (that was what the “end of the world” was all about :-) )

  9. KevinM says:

    Way off topic, but given where this starts and where it goes, the following story-link ought to have steam bursting from the Chiofio’s ears.

    http://www.marklynas.org/2013/01/lecture-to-oxford-farming-conference-3-january-2013/

  10. E.M.Smith says:

    @KevinM: Um, that’s what “Tips” is for up top…

    New Quake:

    Magnitude 8.0 – SANTA CRUZ ISLANDS
    This webpage is being phased out and is no longer maintained. Please use the new Real-time Earthquake Map instead and update your bookmark. See Quick Tips & User Guide.
    2013 February 06 01:12:27 UTC

    Earthquake Details

    This event has been reviewed by a seismologist.

    Magnitude 8.0
    Date-Time

    Wednesday, February 06, 2013 at 01:12:27 UTC
    Wednesday, February 06, 2013 at 12:12:27 PM at epicenter
    Time of Earthquake in other Time Zones

    Location 10.738°S, 165.138°E
    Depth 28.7 km (17.8 miles)
    Region SANTA CRUZ ISLANDS
    Distances 81 km (50 miles) W of Lata, Solomon Islands
    575 km (357 miles) NNW of Luganville, Vanuatu
    581 km (361 miles) ESE of Honiara, Solomon Islands
    847 km (526 miles) NNW of Port-Vila, Vanuatu
    Location Uncertainty horizontal +/- 14.2 km (8.8 miles); depth +/- 5.2 km (3.2 miles)
    Parameters NST=347, Nph=351, Dmin=586.7 km, Rmss=1.28 sec, Gp= 18°,
    M-type=(unknown type), Version=B
    Source

    Magnitude: USGS NEIC (WDCS-D)
    Location: USGS NEIC (WDCS-D)

    Event ID usc000f1s0

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