Sumatran earthquake of October 2010

from Wikipedia, the free encyclopedia
Sumatran earthquake of October 2010
Sumatra earthquake of October 2010 (Sumatra)
Bullseye1.svg
date October 25, 2010
Time 14:42:22 UTC
intensity IV  on the MM scale
Magnitude 7.7  M S
depth 20.6 km
epicenter 3 ° 27 '50 "  S , 100 ° 5' 2"  E Coordinates: 3 ° 27 '50 "  S , 100 ° 5' 2"  O
country Indonesia
Affected places

Mentawai Islands

Tsunami Yes
dead 435,> 100 missing

The Sumatra earthquake of October 2010 was a severe earthquake with a magnitude of 7.7 M s that occurred on October 25, 2010 at 21:42 local time (14:42 UTC ) off the west coast of the Indonesian island of Sumatra . The earthquake struck the same fault that caused the 2004 Indian Ocean earthquake . It was in large parts of the provinces of Bengkulu and West Sumatra felt and generated a local tsunami , the Mentawai Islands met.

Many villages on the islands were affected by the tidal wave, which reached a height of up to three meters and swept up to 600 meters inland. The tsunami caused destruction that left more than 20,000 people homeless. 435 victims of the natural disaster have been confirmed, more than a hundred missing. The subsequent rescue and emergency aid operation was initially hampered by bad weather and the remoteness of the islands, which also contributed to the reluctance to announce the number of victims.

Tectonic overview

Map showing the previous earthquake areas near the earthquake in October 2010

The epicenter of the earthquake was about 240 km west of Bengkulu and 280 km south of Padang near the Mentawai Islands, southwest of southern Pagai . Initially, the United States Geological Survey (USGS) stated that the hypocenter was at a depth of 33 km, but later corrected this to 20.6 km. The intensity of the earthquake was MM IV in Bengkulu and MM III in Padang .

The island of Sumatra lies above the Sunda Megathrust , the zone in which the descending Australian Plate and the overlapping Sunda Plate meet. Movement in this subduction zone is responsible for a number of large megathrust earthquakes . The last sequence of large earthquakes in the region began with the Indian Ocean tsunami in 2004 and closes the earthquake off Sumatra in 2005 and the Sumatra earthquake in March and in September 2007 a. The earthquake of October 2018 was probably the result of a thrust at or near the plate boundary. Measured by the potential for seismic risk, the Sunda Trench can be divided into several segments. The southern segment is on the south side of the island of Siberut . The crack zone of the earthquake of October 25, 2018 lies within this southern segment. Historical earthquakes in this section included the Sumatra earthquake of 1797 and the Sumatra earthquake of 1833 with a magnitude of M w  ~ 9.0.

In contrast to 2004, the tsunami that was triggered was not directed westward and therefore did not affect a number of other states bordering the Indic. It was also noted that the earthquake could be a powerful aftershock of the much larger Sumatran earthquakes of September 2007.

The earthquake occurred around seven hours after the Merapi erupted on the Indonesian island of Java . Because of the distance between the epicenter and the volcano, the two events are believed not to be directly related.

Effects

Epicenter in relation to North and South Pagai

The effects of the earthquake were felt most strongly in the Mentawai Islands off Sumatra. On the island of South Pagai, the tsunami that followed the earthquake reached a height of three meters and sloshed up to 600 meters inland. According to Indonesian officials, more than 20,000 people in the more than twenty towns hit by the tsunami have become homeless , affecting around 4,000 households. The coastal village of Betu Monga on South Pagai was destroyed by the tidal wave and many of its residents are missing. Many residents of the villages of Peurogat and Beleerakso were also reported missing. Eighty percent of the houses in the village of Muntei Baru on North Pagei were damaged or destroyed.

A spokesman for the Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG) announced that the earthquake was felt in several cities in Sumatra, but no property damage or casualties were reported. The Mentawai Islands shielded the Sumatran coast from the full force of the tsunami.

On October 30, the death toll from the effects of the earthquake and tsunami was given as 435, 110 more were still missing, although it is assumed that many of them were washed out to sea by the tidal wave.

Due to bad weather and rough seas, disaster relief workers were initially unable to reach the area. The Indonesian military has been deployed, and international aid organizations have also initiated aid measures. The first aid teams arrived on site two days after the earthquake on October 27th.

Problems with the tsunami early warning system

The BMKG issued a tsunami warning based on seismographic data. The alarm was broadcast on the radio and shouted over loudspeakers from mosques, which in Sumatra caused thousands to flee to higher lands. The alarm was later canceled; However, some officials stated that the tsunami warning system installed after the 2004 seaquake did not function properly. Two of the buoys at sea had been vandalized and were not working. These claims were denied by the German side. The head of the German Indonesian Tsunami Early Warning System (GITEWS) stated that the system "worked very well", only one of the sensors had failed and its failure did not affect the functioning of the system. However, the epicenter of the earthquake was so close to the islands that it was too late to warn, as the tsunami only took five to ten minutes to reach the islands.

Aftershocks

Several aftershocks have been recorded since the original earthquake, the most significant of which are the following:

  • 5.0 - October 25 15:21:12 UTC
  • 6.1 - October 25 19:37:30 UTC
  • 4.9 - October 25 22:10:03 UTC
  • 6.2 - October 25 22:59:53 UTC
  • 5.3 - October 26 10:51:25 UTC
  • 5.3 - Oct 26 11:33:21 UTC
  • 5.0 - October 26 19:40:41 UTC
  • 5.0 - October 26 23:09:47 UTC
  • 5.8 - October 26 23:45:38 UTC

See also

supporting documents

  1. ↑ a b c Magnitude 7.7 - KEPULAUAN MENTAWAI REGION, INDONESIA ( English ) In: earthquake.usgs.gov . USGS . October 25, 2010. Archived from the original on October 28, 2010. Retrieved on October 27, 2010.
  2. ↑ a b Major earthquake strikes off Indonesia ( English ) In: BBC News . British Broadcasting Corporation. October 25, 2010. Retrieved November 1, 2010.
  3. ↑ Tsunami Bulletin ( English ) Pacific Tsunami Warning Center. October 25, 2010. Retrieved November 1, 2010.
  4. ↑ a b Bayo Ismoyu: Death Toll From Indonesian Disasters Tops 400 (English) . In: The Jakarta Globe , October 30, 2010. Archived from the original on September 25, 2012. 
  5. ↑ a b c d Indonesia tsunami: Death toll soars to 282 (English) , BBC News Online. October 27, 2010. Retrieved November 1, 2010. 
  6. ^ John Nedi: Indonesia tsunami kills 113; scores more missing ( English ) Christian Science Monitor. October 26, 2010. Archived from the original on November 1, 2010. Retrieved on November 1, 2010.
  7. ↑ - ( Memento from October 28, 2010 in the Internet Archive )
  8. ↑ K. See: The Sunda megathrust: past, present and future ( English , PDF; 769 kB) Archived from the original on August 1, 2010. Retrieved October 26, 2018.
  9. ↑ R. Bürgmann: Imperfect dominoes . (PDF) In: Nature Geoscience . 2, 2009, pp. 78-88. Retrieved October 26, 2010.
  10. ↑ http://igpphome.ucsd.edu/~shearer/Files/Sumatra_Papers/deshon_grl05.pdf
  11. ↑ a b Sumatra earthquake and tsunami could herald bigger quake ( English ) In: The Great Beyond . Nature. October 27, 2010. Retrieved November 1, 2010.
  12. ↑ a b c d Toni O'Loughlin in Jakarta, Robert Booth and Matthew Weaver: Indonesia death toll reaches 300 with more feared after twin disasters. (English) . In: The Guardian , October 27, 2010. Retrieved October 28, 2010. 
  13. ↑ a b c We Couldn't Outrun Killer Wave: Villager ( English ) The Jakarta Globe. October 28, 2010. Archived from the original on October 30, 2010. Retrieved on October 28, 2010.
  14. ↑ 108 dead, 500 missing after tsunami hits Indonesia ( English ) channelnewsasia.com. October 26, 2010. Retrieved October 27, 2010.
  15. ↑ Tsunami warning relaxed after Indonesia quake ( English ) Reuters. October 25, 2010. Retrieved October 26, 2010.
  16. ^ Indonesian tsunami warning system 'was not working' (English) , Daily Telegraph. Retrieved November 1, 2010. 
  17. ↑ Death Toll From Indonesian Disasters Tops 400 (English) . In: NPR , October 28, 2010.  
  18. ↑ https://earthobservatory.nasa.gov/images/46607/77-magnitude-quake-off-sumatra
  19. ^ Agence France-Presse: Major 7.7 quake strikes Indonesia . October 25, 2010. Retrieved October 27, 2010.
  20. ↑ Magnitude 4.9 - KEPULAUAN MENTAWAI REGION, INDONESIA . In: earthquake.usgs.gov . USGS. October 25, 2010. Archived from the original on October 28, 2010. Retrieved on October 27, 2010.
  21. ↑ Magnitude 6.2 - KEPULAUAN MENTAWAI REGION, INDONESIA . In: earthquake.usgs.gov . USGS. October 25, 2010. Archived from the original on October 27, 2010. Retrieved on October 27, 2010.
  22. ↑ Magnitude 5.3 - SOUTHWEST OF SUMATRA, INDONESIA . In: earthquake.usgs.gov . USGS. October 26, 2010. Retrieved October 27, 2010.
  23. ↑ Magnitude 5.3 - KEPULAUAN MENTAWAI REGION, INDONESIA . In: earthquake.usgs.gov . USGS. October 26, 2010. Retrieved October 27, 2010.
  24. ↑ Magnitude 5.0 - SOUTHWEST OF SUMATRA, INDONESIA . In: earthquake.usgs.gov . USGS. October 26, 2010. Retrieved October 27, 2010.
  25. ↑ Magnitude 5.0 - SOUTHWEST OF SUMATRA, INDONESIA . In: earthquake.usgs.gov . USGS. October 26, 2010. Retrieved October 27, 2010.
  26. ↑ Magnitude 5.8 - KEPULAUAN MENTAWAI REGION, INDONESIA . In: earthquake.usgs.gov . USGS. October 26, 2010. Retrieved October 27, 2010.

Web links