2012 Tabriz earthquake
| 2012 Tabriz earthquake | |||
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| Coordinates | 38 ° 19 '19 " N , 46 ° 53' 17" E | ||
| date | August 11, 2012 | ||
| Time | 12:23:17 UTC | ||
| Magnitude | 6.4 M W | ||
| depth | 9.9 km | ||
| epicenter | Near Tabriz
(60 km east-northeast )
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| country | Iran | ||
| Affected places | |||
| dead | 306 | ||
| Injured | 3037 | ||
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The 2012 Tabriz earthquake - also known as the Ahar-Varzaqan Doublet earthquake - occurred on August 11, 2012 at 4:53 p.m. local time (12:23:18 UTC ). Its epicenter was in the province of East Azerbaijan , around 60 kilometers northeast of the metropolis of Tabriz in Iran . The United States Geological Survey specified the strength of this earthquake with the moment magnitude M W = 6.4. Just eleven minutes after the first major quake, another earthquake with M W = 6.2 occurred at 12:34:35 a.m. (UTC) . Because of the similar magnitude and the short time interval between the two earthquakes, the events are regarded as an earthquake doublet. The number of victims amounts to at least 306 dead and over 3,000 injured, mostly in rural areas northeast of Tabriz in and around the cities of Ahar and Varzaqan . The earthquakes were also felt in the neighboring states of Azerbaijan and Armenia , but there was no significant damage to persons or property.
As a tectonically very active area with a large number of geological faults, Iran is frequently hit by strong earthquakes. The most devastating in the recent past were the Manjil Rudbar earthquake in 1990 and the earthquake in Bam in 2003 .
geology
Iran lies in the complex interaction zone of a converging plate boundary . This is where the Arabian plate meets the Eurasian plate and is one of the largest interaction zones of its kind in the world. In the north-west of Iran, the Arabian plate moves northwards at around 20 mm per year, relative to the Eurasian plate. The deformation in the region of Tabriz is the North Tabriz Fault dominated (NTF), a WNW-ESE trending strike-slip (English. Strike-slip fault ). This has been responsible for seven historical earthquakes with a magnitude of at least 6.0 since 858 . Another known disruption is striking in the WO direction between the cities of Ahar and Heriz . The Tabriz earthquake is an intraplate tectonic event that occurred 300 kilometers east of the Eurasian-Arab plate boundary. The first major quake occurred along a WO oriented fault and shows a clear dextral blade displacement mechanism. For the second main quake, the mechanism can not be determined with absolute certainty, but featured a strike-slip portion and a deferment santeil. The orientation of the causing disturbance is more SW-NE oriented.
Damage and sacrifice
Rescue organizations reported that the hardest hit areas were difficult to get to because the roads were destroyed and traffic congestion made it difficult to get there. The first aid measures got off to a slow start; the mostly poorly equipped hospitals in the vicinity of the earthquake were completely overloaded. The greatest damage and the highest number of victims occurred in and around the cities of Ahar , Varzaqan and Heriz . According to the Red Crescent , over 1,000 locations were affected by the earthquake. Damage of more than 70% was recorded in around 130 locations, and around 20 locations were completely destroyed. Since the earthquake occurred at 4:53 p.m. local time, many people were not in their homes, which should have had a positive effect on the number of victims. However, a particularly large number of women and children fell victim to the earthquake, as they tended to stay in the poorly stable mud houses while the men were working. As a result, many people spent the following night outdoors for fear of aftershocks.
Rescue teams worked through the night to track down people who had been buried, but between ten and twenty locations near the epicenter were cut off from the outside world immediately after the earthquake and could only be reached later. The Iranian government said that around 16,000 people spent the first night after the earthquake in emergency shelters. On the first day after the earthquake, emergency shelters were provided for over 36,000 people, as well as 44,000 food packages and 5,600 tents.
Aftershocks
In addition to the two main earthquakes of August 11, 2012, around 1,110 aftershocks with a local magnitude of M L ≥ 2.0 occurred by the beginning of October . After a somewhat quieter phase with 107 aftershocks ( M L ≥ 2.0) until the beginning of November, the strongest measured aftershock with a magnitude of M W = 5.5 occurred on November 7, 2012 at 06:26 a.m. (UTC) . This triggered a new sequence of earthquakes at the western end of the fracture surface of the first major quake.
Web links
Individual evidence
- ↑ a b M6.4 - 26km WSW of Ahar, Iran. United States Geological Survey, August 11, 2012, accessed September 1, 2012 .
- ↑ M6.2 - 30km WSW of Ahar, Iran. United States Geological Survey, August 11, 2012, accessed September 1, 2012 .
- ↑ a b c Stefanie Donner, Abdolreza Ghods, Frank Krüger, Dirk Rößler, Angela Landgraf: The Ahar ‐ Varzeghan Earthquake Doublet (Mw 6.4 and 6.2) of 11 August 2012: Regional Seismic Moment Tensors and a Seismotectonic Interpretation . In: Bulletin of the Seismological Society of America . tape 105 , 2A, February 10, 2015, ISSN 0037-1106 , p. 791-807 , doi : 10.1785 / 0120140042 (English, geoscienceworld.org [accessed September 30, 2019]).
- ↑ Iran raises quake death toll to 306. (No longer available online.) The New Zealand Heral, August 13, 2012, archived from the original on August 14, 2012 ; accessed on September 1, 2012 (English). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Search For Survivors After Devastating Iran Earthquakes. Radio Free Europa Radio Liberty, August 11, 2012, accessed September 1, 2012 .
- ↑ M. Allen, J. Jackson, R. Walker: Late Cenozoic reorganization of the Arabia-Eurasia collision and the comparison of short-term and long-term deformation rates Archived from the original on January 12, 2012. Info: The archive link was automatically used and not yet tested. Please check the original and archive link according to the instructions and then remove this notice. In: American Geophysical Union (Ed.): Tectonics . 23, 2004. Retrieved September 1, 2012.
- ^ AS Moradi, D. Hatzfeld, M. Tatar: Microseismicity and seismotectonics of the North Tabriz fault (Iran) . In: Elsevier (Ed.): Tectonophysics . 506, No. 1-4, 2011, pp. 22-30. bibcode : 2011Tectp.506 ... 22M . Accessed September 1, 2012.
- ↑ M. Hoseinpour, M. Zare: Seismic Hazard Assessment of Tabriz, a City in the Northwest of Iran (PDF; 1.3 MB) Science Information Database. 2009. Retrieved September 1, 2012.
- ↑ a b Two earthquakes in Iran kill 300 and injure 5,000. Reuters, August 12, 2012, accessed September 1, 2012 .
- ↑ 200 Rescued in Iran After Quakes; Death Toll Rises to 300. In: The New York Times. August 12, 2012, accessed September 1, 2012 .
