Info Detail Gempa Kepulauan Mentawai
- This event has been reviewed by a seismologist.
|Depth||20.6 km (12.8 miles)|
|Region||KEPULAUAN MENTAWAI REGION, INDONESIA|
|Distances||240 km (150 miles) W of Bengkulu, Sumatra, Indonesia
280 km (175 miles) S of Padang, Sumatra, Indonesia
305 km (190 miles) W of Lubuklinggau, Sumatra, Indonesia
795 km (500 miles) WNW of JAKARTA, Java, Indonesia
|Location Uncertainty||horizontal +/- 5.3 km (3.3 miles); depth +/- 3.4 km (2.1 miles)|
|Parameters||NST=297, Nph=297, Dmin=330.2 km, Rmss=1.16 sec, Gp= 22°,
M-type=surface wave magnitude (Ms), Version=V
The Pulau Pagai Selatan, Sumatra earthquake of October 25, 2010 occurred as a result of thrust faulting on or near the subduction interface plate boundary between the Australia and Sunda plates. At the location of this earthquake, the Australia Plate move north-northeast with respect to the Sunda plate at a velocity of approximately 57-69 mm/yr. On the basis of the currently available fault mechanism information and earthquake depth it is likely that this earthquake occurred along the plate interface. The subduction zone adjacent to the region of this event last slipped during the Mw 8.5 and 7.9 earthquakes of September 2007, and today’s event appears to have occurred near the rupture zones of those earthquakes. Today’s earthquake is the latest in a sequence of large ruptures along the Sunda megathrust, including a M 9.1 earthquake that ruptured to within 800 km north of this earthquake in 2004; a M 8.6 700 km to the north between Nias and Simeulue in 2005; and a M 7.5 300 km to the north near Padang in 2009. Today’s earthquake occurred near the southern edge of a Mw 8.7-8.9 rupture in 1797 and within the rupture area of a Mw 8.9-9.1 earthquake in 1833.
000 WEIO21 PHEB 251657 TSUIOX TSUNAMI BULLETIN NUMBER 004 PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS ISSUED AT 1657Z 25 OCT 2010 THIS BULLETIN IS FOR ALL AREAS OF THE INDIAN OCEAN. ... TSUNAMI WATCH CANCELLATION SUPPLEMENT ... 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 - 1442Z 25 OCT 2010 COORDINATES - 3.1 SOUTH 100.1 EAST DEPTH - 33 KM LOCATION - SOUTHERN SUMATRA INDONESIA MAGNITUDE - 7.5 MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY GAUGE LOCATION LAT LON TIME AMPL PER ------------------ ----- ------ ----- --------------- ----- TANAHBALAH ID 0.5S 98.5E 1605Z 0.23M / 0.8FT 16MIN PADANG ID 0.9S 100.4E 1558Z 0.33M / 1.1FT 14MIN ENGGANO ID 5.3S 102.3E 1528Z 0.27M / 0.9FT 06MIN COCOS ISLAND AU 12.1S 96.9E 1612Z 0.11M / 0.4FT 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. 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. ...SP...