Zware aardbeving (8,7) Indonesië - 11-04-2012

[sylvester1986]

Zware aardbeving Indonesië

ATJEH -  Indonesië is woensdag opgeschrikt door een zeer zware aardbeving voor de kust van Sumatra. De beving had een kracht van 8.7 op de schaal van Richter en werd tot in Singapore, Thailand en zuid-India gevoeld. Er is een tsunamiwaarschuwing uitgegaan die voor de hele Indische Oceaan van kracht is. Ook voor Sri Lanka en India geldt inmiddels een tsunami-alarm.

Het epicentrum van de aardbeving lag volgens Indonesische en Amerikaanse seismologische instellingen ruim 30 kilometer onder de zeebodem, circa 430 kilometer ten westen van het noordelijk deel van het eiland. Na de beving volgde een naschok met een kracht van 6.5 op de schaal van Richter. De Indonesische overheid heeft een reddingsteam naar Atjeh gestuurd. De president heeft verklaard dat er nog geen schade of slachtoffers zijn gemeld. Ook is er volgens hem op het moment geen direct gevaar voor een tsunami.
Hetzelfde gebied werd eind 2004 verwoest door een enorme tsunami of vloedgolf die een gevolg was van een aardbeving onder de zeebodem ten westen van Sumatra. Vloedgolven troffen toen zelfs de kust van Oost-Afrika. Naar schatting een kwart miljoen mensen verloren het leven.

http://www.telegraaf.nl/buitenland/11886051/__Zware_aardbeving_Atjeh__.html

[sylvester1986]

Update.

De vrees voor een verwoestende tsunami zoals die in 2004 is afgenomen omdat het zeewater zich niet heeft teruggetrokken. Dat vormde bijvoorbeeld in 2004 de voorbode van een enorme vloedgolf na de aardbeving die een kracht had van 9,1 op de schaal van Richter. Het gevaar zou nu vele minder zijn door het soort aardbeving. Woensdag beefde de aarde ten westen van Sumatra meer op en neer dan heen en weer. Dat verkleint de kans op een vloedgolf, aldus waarnemers.

http://www.telegraaf.nl/buitenland/11886051/__Zware_aardbeving_Atjeh__.html

[ChrisRT]

SUNAMI BULLETIN NUMBER 003
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 1014Z 11 APR 2012

THIS BULLETIN IS FOR ALL AREAS OF THE INDIAN OCEAN.

... AN INDIAN-OCEAN-WIDE TSUNAMI WATCH IS IN EFFECT ...

A TSUNAMI WATCH IS IN EFFECT FOR

 INDONESIA / INDIA / AUSTRALIA / SRI LANKA / MYANMAR / THAILAND /
 MALDIVES / UNITED KINGDOM / MALAYSIA / MAURITIUS / REUNION /
 SEYCHELLES / OMAN / PAKISTAN / SOMALIA / MADAGASCAR / IRAN /
 UAE / YEMEN / COMORES / MOZAMBIQUE / KENYA / TANZANIA /
 CROZET ISLANDS / BANGLADESH / KERGUELEN ISLANDS / SOUTH AFRICA /
 SINGAPORE

THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES.  ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE
DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND
ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

 ORIGIN TIME -  0839Z 11 APR 2012
 COORDINATES -   2.3 NORTH   93.1 EAST
 LOCATION    -  OFF W COAST OF NORTHERN SUMATRA
 MAGNITUDE   -  8.7

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

 GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN
 MEULABOH ID           4.1N  96.1E  0950Z   0.27M /  0.9FT  14MIN
 SABANG ID             5.8N  95.3E  0956Z   0.31M /  1.0FT  08MIN

 LAT  - LATITUDE (N-NORTH, S-SOUTH)
 LON  - LONGITUDE (E-EAST, W-WEST)
 TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
 AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
        IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
        VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
 PER  - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

 NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
        ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
         MEASUREMENTS AT SIMILAR LOCATIONS.

Bron: http://ptwc.weather.gov/ptwc/?region=3

[Danny722]

Update.

De vrees voor een verwoestende tsunami zoals die in 2004 is afgenomen omdat het zeewater zich niet heeft teruggetrokken. http://www.telegraaf.nl/buitenland/11886051/__Zware_aardbeving_Atjeh__.html

Niet?

https://t.co/RkRkb7cm

Overigens houdt Geenstijl, zoals gebruikelijk bij grote incidenten, een liveblog bij.

[ChrisRT]

Volgens de PACIFIC TSUNAMI WARNING CENTER (PTWC) is er maximaal een vloedgolf van ca 30 cm te verwachten

GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN
 MEULABOH ID           4.1N  96.1E  0950Z   0.27M /  0.9FT  14MIN
 SABANG ID             5.8N  95.3E  0956Z   0.31M /  1.0FT  08MIN

[sylvester1986]

Niet?

https://t.co/RkRkb7cm

[ChrisRT]

TSUNAMI BULLETIN NUMBER 004
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 1054Z 11 APR 2012

THIS BULLETIN IS FOR ALL AREAS OF THE INDIAN OCEAN.

... AN INDIAN-OCEAN-WIDE TSUNAMI WATCH IS IN EFFECT ...

... A MAJOR AFTERSHOCK OCCURRED AT 11:43Z WITH MAGNITUDE 8.3 ...

A TSUNAMI WATCH IS STILL IN EFFECT FOR

 INDONESIA / INDIA / AUSTRALIA / SRI LANKA / MYANMAR / THAILAND /
 MALDIVES / UNITED KINGDOM / MALAYSIA / MAURITIUS / REUNION /
 SEYCHELLES / OMAN / PAKISTAN / SOMALIA / MADAGASCAR / IRAN /
 UAE / YEMEN / COMORES / MOZAMBIQUE / KENYA / TANZANIA /
 CROZET ISLANDS / BANGLADESH / KERGUELEN ISLANDS / SOUTH AFRICA /
 SINGAPORE

THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES.  ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE
DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND
ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

 ORIGIN TIME -  0839Z 11 APR 2012
 COORDINATES -   2.3 NORTH   93.1 EAST
 LOCATION    -  OFF W COAST OF NORTHERN SUMATRA
 MAGNITUDE   -  8.7

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

 GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 TELUKDALAM ID         0.6N  97.8E  0952Z   0.15M /  0.5FT  08MIN
 SABANG ID             5.8N  95.3E  1010Z   0.36M /  1.2FT  06MIN
 MEULABOH ID           4.1N  96.1E  1007Z   1.06M /  3.5FT  12MIN
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN
 SABANG ID             5.8N  95.3E  0956Z   0.31M /  1.0FT  08MIN

 LAT  - LATITUDE (N-NORTH, S-SOUTH)
 LON  - LONGITUDE (E-EAST, W-WEST)
 TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
 AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
        IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
        VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
 PER  - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

 NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
        ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
         MEASUREMENTS AT SIMILAR LOCATIONS.

EVALUATION

 SEA LEVEL READINGS INDICATE A TSUNAMI WAS GENERATED. IT MAY
 ALREADY HAVE BEEN DESTRUCTIVE ALONG SOME COASTS.

 BASED ON THESE DATA THE THREAT CONTINUES FOR ALL COASTAL AREAS OF
 THE INDIAN OCEAN. FOR THOSE AREAS - WHEN NO MAJOR WAVES HAVE
 OCCURRED FOR AT LEAST TWO HOURS AFTER THE ESTIMATED ARRIVAL TIME
 OR DAMAGING WAVES HAVE NOT OCCURRED FOR AT LEAST TWO HOURS THEN
 LOCAL AUTHORITIES CAN ASSUME THE THREAT IS PASSED. DANGER TO
 BOATS AND COASTAL STRUCTURES CAN CONTINUE FOR SEVERAL HOURS DUE
 TO RAPID CURRENTS.  AS LOCAL CONDITIONS CAN CAUSE A WIDE
 VARIATION IN TSUNAMI WAVE ACTION THE ALL CLEAR DETERMINATION MUST
 BE MADE BY LOCAL AUTHORITIES.

Bron: http://ptwc.weather.gov/ptwc/?region=3

[ChrisRT]

TSUNAMI BULLETIN NUMBER 005
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 1151Z 11 APR 2012

THIS BULLETIN IS FOR ALL AREAS OF THE INDIAN OCEAN.

... AN INDIAN-OCEAN-WIDE TSUNAMI WATCH IS IN EFFECT ...

... A MAJOR AFTERSHOCK OCCURRED AT 1043Z WITH MAGNITUDE 8.3 ...

... THE WATCH AREA IS NOW REDUCED ...

A TSUNAMI WATCH IS IN EFFECT FOR

 INDONESIA / INDIA / SRI LANKA / MALDIVES / UNITED KINGDOM

THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES.  ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE
DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND
ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

 ORIGIN TIME -  0839Z 11 APR 2012
 COORDINATES -   2.3 NORTH   93.1 EAST
 LOCATION    -  OFF W COAST OF NORTHERN SUMATRA
 MAGNITUDE   -  8.7

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

 GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 TRINCONMALEE LK       8.6N  81.2E  1116Z   0.04M /  0.1FT  18MIN
 COCOS ISLAND AU      12.1S  96.9E  1102Z   0.08M /  0.3FT  18MIN
 TELUKDALAM ID         0.6N  97.8E  1045Z   0.19M /  0.6FT  10MIN
 SABANG ID             5.8N  95.3E  1010Z   0.36M /  1.2FT  06MIN
MEULABOH ID           4.1N  96.1E  1007Z   1.06M /  3.5FT  12MIN
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN

 LAT  - LATITUDE (N-NORTH, S-SOUTH)
 LON  - LONGITUDE (E-EAST, W-WEST)
 TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
 AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
        IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
        VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
 PER  - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

 NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
        ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
         MEASUREMENTS AT SIMILAR LOCATIONS.

[guest8310]

Volgens de PACIFIC TSUNAMI WARNING CENTER (PTWC) is er maximaal een vloedgolf van ca 30 cm te verwachten

GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN
 MEULABOH ID           4.1N  96.1E  0950Z   0.27M /  0.9FT  14MIN
 SABANG ID             5.8N  95.3E  0956Z   0.31M /  1.0FT  08MIN

Helaas is dat niet een terechte conclusie. Zoals ook in hun eigen NOTE staat, zijn dit meetpunten op open zee. De golfhoogtes zijn dus metingen van diepwatergolven, die beduidend lager zijn dan de daadwerkelijke golfhoogte zodra de golf de kust bereikt. Zodra dit gebeurd zal de golf tegen de bodem van de zee "oplopen" en zo totaal verschillende karakteristieken krijgen. E.e.a. Is afhankelijk van de exacte omstandigheden, maar in principe zullen de golven hoger worden, de golfperiode afnemen (dichter op elkaar) en de golfsnelheid neemt ook af.

De gemeten waardes van deze meetboeien geven ons (zonder verdere lokale kennis) dus Geen enkele informatie over de daadwerkelijk optredende golfhoogtes op de verschillende lokaties langs de kust.

[guest8310]

Tsunami watch is opgeheven, gevaar zou dus grotendeels geweken moeten zijn...

000
WEIO21 PHEB 111236
TSUIOX

TSUNAMI BULLETIN NUMBER 006
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 1236Z 11 APR 2012

THIS BULLETIN IS FOR ALL AREAS OF THE INDIAN OCEAN.

... THE TSUNAMI WATCH IS CANCELLED FOR BOTH MAIN SHOCK
AT 0839Z AND AFTERSHOCK AT 1043Z ...

THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES.  ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE
DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND
ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

 ORIGIN TIME -  0839Z 11 APR 2012
 COORDINATES -   2.3 NORTH   93.1 EAST
 LOCATION    -  OFF W COAST OF NORTHERN SUMATRA
 MAGNITUDE   -  8.7

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY

 GAUGE LOCATION        LAT   LON    TIME        AMPL         PER
 -------------------  ----- ------  -----  ---------------  -----
 KO TAPHAO NOI TH      7.8N  98.4E  1143Z   0.05M /  0.2FT  06MIN
 ENGGANO ID            5.3S 102.3E  1104Z   0.12M /  0.4FT  04MIN
 TRINCONMALEE LK       8.6N  81.2E  1129Z   0.06M /  0.2FT  16MIN
 TELUKDALAM ID         0.6N  97.8E  1044Z   0.22M /  0.7FT  14MIN
 COCOS ISLAND AU      12.1S  96.9E  1102Z   0.08M /  0.3FT  18MIN
 SABANG ID             5.8N  95.3E  1010Z   0.36M /  1.2FT  06MIN
 MEULABOH ID           4.1N  96.1E  1007Z   1.06M /  3.5FT  12MIN
 DART 23401            8.9N  88.5E  0956Z   0.03M /  0.1FT  06MIN

 LAT  - LATITUDE (N-NORTH, S-SOUTH)
 LON  - LONGITUDE (E-EAST, W-WEST)
 TIME - TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
 AMPL - TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
        IT IS ...NOT... CREST-TO-TROUGH WAVE HEIGHT.
        VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
 PER  - PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.

 NOTE - DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
        ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
         MEASUREMENTS AT SIMILAR LOCATIONS.

EVALUATION

 A SIGNIFICANT TSUNAMI WAS GENERATED BY THIS EARTHQUAKE.
 HOWEVER...SEA LEVEL READINGS NOW INDICATE THAT THE THREAT HAS
 DIMINISHED OR IS OVER FOR MOST AREAS.  THEREFORE THE TSUNAMI
 WATCH ISSUED BY THIS CENTER IS NOW CANCELLED.

 FOR ANY AFFECTED AREAS - WHEN NO MAJOR WAVES HAVE OCCURRED FOR AT
 LEAST TWO HOURS AFTER THE ESTIMATED ARRIVAL TIME OR DAMAGING WAVES
 HAVE NOT OCCURRED FOR AT LEAST TWO HOURS THEN LOCAL AUTHORITIES
 CAN ASSUME THE THREAT IS PASSED. DANGER TO BOATS AND COASTAL
 STRUCTURES CAN CONTINUE FOR SEVERAL HOURS DUE TO RAPID CURRENTS.
 AS LOCAL CONDITIONS CAN CAUSE A WIDE VARIATION IN TSUNAMI WAVE
 ACTION THE ALL CLEAR DETERMINATION MUST BE MADE BY LOCAL
 AUTHORITIES.

THIS WILL BE THE FINAL BULLETIN ISSUED BY THE PACIFIC TSUNAMI
WARNING CENTER FOR THIS EVENT UNLESS ADDITIONAL INFORMATION
BECOMES AVAILABLE.

THE JAPAN METEOROLOGICAL AGENCY MAY ISSUE ADDITIONAL INFORMATION
FOR THIS EVENT. IN THE CASE OF CONFLICTING INFORMATION...THE
MORE CONSERVATIVE INFORMATION SHOULD BE USED FOR SAFETY.