Major Earthquake off alaska

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Potential Tsunami from M7.7 earthquake off Alaska – ALL WARNINGS and ADVISORIES are now CANCELED

Last update: January 5, 2013 at 4:57 pm by By

Earthquake overview : A major earthquake has struck off the Alaskan coast with the potential for a tsunami. Finally, no dangerous tsunami was generated but during a couple of hours people had to evacuate to higher grounds in many locations

7.4

First update – Massive earthquake in Alaska
We have just received the report that a massive 7.8 Magnitude quake struck Alaska
More details in a moment

Most important Earthquake Data:
Magnitude : M7.7
UTC Time : 5th January 2013, 08:58:19 UTC
Local time at epicenter : 4th January 2013, 23:58:19 UTC-09:00
Depth (Hypocenter) : 9.9km
Geo-location(s) : 101 km (63 miles) SW (221 degrees) of Edna Bay, AK
102 km (64 miles) W (259 degrees) of Craig, AK
106 km (66 miles) S (182 degrees) of Port Alexander, AK
314km (195mi) WNW of Prince Rupert, Canada
335km (208mi) S of Juneau, Alaska
1032 km (641 miles) NW (315 degrees) of Vancouver, British Columbia, Canada

ectonic Summary
The January 5, 2013 M 7.5 earthquake off the west coast of southeastern Alaska occurred as a result of shallow strike-slip faulting on or near the plate boundary between the Pacific and North America plates.  At the location of this earthquake, the Pacific plate is moving approximately northwestward with respect to the North America plate at a velocity of 51 mm/yr.
This earthquake is likely associated with relative motion across the Queen Charlotte fault system offshore of British Columbia, Canada, which forms the major expression of the Pacific:North America plate boundary in this region. The surrounding area of the plate boundary has hosted 8 earthquakes of magnitude 6 or greater over the past 40 years; In 1949, a M 8.1 earthquake occurred close to the Pacific:North America plate boundary approximately 230 km to the south east of the January 5th earthquake,  as a result of strike-slip faulting. In October of 2012, a M 7.8 earthquake occurred approximately 330 km to the south east of the January 5th event, slightly inboard of the plate boundary, and was associated with oblique-thrust faulting. The latter earthquake was likely an expression of the oblique component of deformation along this plate boundary system. The January 5th, 2013 earthquake is related to that Haida Gwai earthquake three months previously, and is an expression of deformation along the same plate boundary system.

Update 16:52 UTC : This earthquake was shallow, strike-slip and possible on Queen Charlotte Fault & few 100 km N of Haida Gwaii thrust quake
– We thank our many readers to send us your experiences almost immediately after the shaking stopped and before we got the official seismological data

Update 13:24 UTC : Most of the Pacific West Coast people  (USA, Alaska and Canada) have returned to their beds
– Only few of them will feel the many moderate aftershocks which will continue for many days and even weeks

Update 12:31 UTC : Most recent and normally last Tsunami bulletin for Alaska, British Columbia and the West Coast

PUBLIC TSUNAMI MESSAGE NUMBER 4 – NWS WEST COAST/ALASKA TSUNAMI WARNING CENTER PALMER AK
158 AM AKST SAT JAN 5 2013

…THE TSUNAMI WARNING IS CANCELLED…

CANCELLATIONS
————-
* THE TSUNAMI WARNING IS CANCELED FOR THE COASTAL AREAS OF BRITISH COLUMBIA AND ALASKA FROM THE NORTH TIP OF VANCOUVER ISLAND BRITISH COLUMBIA TO CAPE FAIRWEATHER ALASKA/LOCATED 80 MILES SE OF YAKUTAT/

IMPACTS – UPDATED
—————–
* A TSUNAMI WAS GENERATED DURING THIS EVENT BUT NO LONGER POSES A THREAT.
* SOME AREAS MAY CONTINUE TO SEE SMALL SEA LEVEL CHANGES.
* THE DETERMINATION TO RE-OCCUPY HAZARD ZONES MUST BE MADE BY LOCAL OFFICIALS.

RECOMMENDED ACTIONS – UPDATED
—————————–
* DO NOT RE-OCCUPY HAZARD ZONES UNTIL LOCAL EMERGENCY OFFICIALS INDICATE IT IS SAFE TO DO SO.

OBSERVATIONS OF TSUNAMI ACTIVITY – UPDATED
——————————————
TIME OBSERVED MAX  SITE OF MEASUREMENT TSUNAMI HEIGHT
—————————- ————— ————–
PORT ALEXANDER AK 1026 UTC 01-05 – 00.5FT
SITKA AK 1041 UTC 01-05 – 00.3FT

HEIGHT – OBSERVED MAX TSUNAMI HEIGHT IS THE WATER LEVEL ABOVE THE
TIDE LEVEL AT THE TIME OF MEASUREMENT.

DEEP OCEAN PRESSURE SENSORS DID NOT RECORD A TSUNAMI.

Update 11:01 UTC : GREAT NEWS :  ALL WARNINGS and ADVISORIES are now CANCELED

Update 10:44 UTC : Nothing really dramatic has happened and will probably not happen also.
Port Alexander, Alaska, sees 6-inch rise in sea level after magnitude 7.5 earthquake
Some warnings remain in effect but maybe downgraded soon :  THE COASTAL AREAS OF BRITISH COLUMBIA AND ALASKA FROM THE NORTH TIP OF VANCOUVER ISLAND BRITISH COLUMBIA TO CAPE FAIRWEATHER ALASKA/LOCATED 80 MILES SE OF YAKUTAT/

PARTLY GOOD NEWS

A NUMBER OF ADVISORY and WARNING CANCELLATIONS
-------------
* THE TSUNAMI ADVISORY IS CANCELED FOR THE COASTAL AREAS OF BRITISH COLUMBIA FROM THE WASHINGTON-BRITISH COLUMBIA BORDER TO THE NORTH TIP OF VANCOUVER ISLAND BRITISH COLUMBIA
* THE TSUNAMI WARNING IS CANCELED FOR THE COASTAL AREAS OF ALASKA FROM CAPE FAIRWEATHER ALASKA/LOCATED 80 MILES SE OF YAKUTAT/ TO CAPE SUCKLING ALASKA/LOCATED 75 MILES SE OF CORDOVA/
* THE TSUNAMI ADVISORY IS CANCELED FOR THE COASTAL AREAS OF ALASKA FROM CAPE SUCKLING ALASKA/LOCATED 75 MILES SE OF CORDOVA/ TO KENNEDY ENTRANCE ALASKA/LOCATED 40 MILES SW OF HOMER/

Update 10:18 UTC :  Some distances from the epicenter to important locations on land
106km (66mi) WSW of Craig, Alaska
304km (189mi) WNW of Prince Rupert, Canada
341km (212mi) S of Juneau, Alaska
404km (251mi) WNW of Terrace, Canada
610km (379mi) S of Whitehorse, Canada

Screen Shot 2013-01-05 at 11.55.02

…THE TSUNAMI WARNINGS REMAINS IN EFFECT…
…THE TSUNAMI ADVISORIES REMAINS IN EFFECT…

If you are a twitter user, we advise you to subscribe to our @quake_Tracker4 or one of the others. It will not only send earthquake notifications, but also I Have Felt It reports and Tsunami alerts

Update 10:08 UTC :  Good news for the broader connected Pacific / Statement for the Pacific Tsunami and weather Center :

NO TSUNAMI THREAT EXISTS FOR OTHER COASTAL AREAS IN THE PACIFIC  ALTHOUGH SOME OTHER AREAS MAY EXPERIENCE SMALL NON-DESTRUCTIVE  SEA LEVEL CHANGES LASTING UP TO SEVERAL HOURS.

Update 10:12 UTC : Tsunami advisory in effect for Prince Rupert. RCMP members going door to door and evacuating residents close to the shore.

Update 10:04 UTC : USGS has now downgraded the Magnitude from 7.7 to 7.5 with a little change in intensities but an important change for an eventual Tsunami potential

Update 09:49 UTC : A visual overview of the Tsunami a warning (red) and Tsunami advisory (orange) locations along the coast. Red means get away from the coast and walk urgently to higher grounds – Orange : be aware of strong waves and potentially higher tides

Screen Shot 2013-01-05 at 10.39.01

Update 09:34 UTC : Our main concern goes to the fisheries in case of a widespread tsunami.

for more information, go to:    http://earthquake-report.com/2013/01/05/potential-tsunami-from-m7-7-earthquake-off-alaska-warning-in-effect/