1139 Ganja earthquake

1139 Ganja earthquake
1139 Ganja earthquake is located in Azerbaijan
1139 Ganja earthquake
Local date30 September 1139 (1139-09-30)[1]
Magnitude7.7 MLH, 7.5 Ms, 7.0–7.3 Mw
Depth23–16 km (14.3–9.9 mi)
Epicenter40°18′N 46°12′E / 40.3°N 46.2°E / 40.3; 46.2[2]
Areas affectedSeljuk Empire (present-day Azerbaijan)
Max. intensityMMI IX (Violent) or MMI XI (Extreme)
Casualties230,000–300,000 dead (estimation)

The 1139 Ganja earthquake was one of the worst seismic events in history. It affected the Seljuk Empire and the Kingdom of Georgia, in modern-day Azerbaijan and Georgia. The earthquake had an estimated magnitude of 7.7 MLH, 7.5 Ms and 7.0–7.3 Mw. A disputed death toll of 230,000–300,000 resulted from this event, making it one of the deadliest earthquakes ever recorded.[3]

Tectonic setting

The Eurasia-African-Arabian-Indian convergent zone

Azerbaijan, Armenia and Georgia are located in an area of high seismic activity as both countries are situated in the collision zone between the Eurasian and Arabian plates. The collision zone consists of an accreted island arc that collided after the closure of the Tethys Ocean, continental blocks, and sediments from the Mesozoic and Tertiary eras. The area is separated into three geographical regions; Lesser Caucasus, Kura Basin and Greater Caucasus. Seismic activity in the Lesser Caucasus is typically associated with strike-slip faults with vertical dip angles. In the Greater Caucasus, seismic activity corresponds to thrust faulting. Extending 100–160 km (62–99 mi) beneath the Greater Caucasus is the remnant of a subducted tectonic plate after the ocean closed.[4] Earthquakes are caused by crustal compression and shear as the two tectonic plates interact.[5]

Earthquake

The earthquake had an estimated moment magnitude of 7.0–7.3 and 7.7 or 7.5 on the surface-wave magnitude scale at a depth of 16–23 kilometres (9.9–14.3 mi).[2][6][7] A maximum intensity of IX (Violent) or XI (Extreme) on the Mercalli intensity scale was assigned.[8] It was also perceived as far as Aleppo where the felt intensity was II (Weak).[9]

An epicenter location at 40°18′N 46°12′E / 40.3°N 46.2°E / 40.3; 46.2, near Ganja, was suggested by researchers. This region of the Lesser Caucasus is dominated by oblique and strike-slip tectonics. The fault responsible for the earthquake, the Pambak-Sevan-Syunik Fault, is a 490-kilometer-long WNW–ESE striking strike-slip fault. For the majority of its length, it demonstrates right-lateral displacement, but at the westernmost segment, its slip sense is left-lateral. The earthquake ruptured the Mrav segment of the fault at its eastern end. Unlike the rest of the Pambak-Sevan-Syunik Fault, the Mrav segment is characterized by a series of north-dipping thrust faults.[10] Paleoseismology in the region indicate large earthquakes of up to Mw  7.5 have occurred on the fault.[11] The Pambak-Sevan-Syunik Fault was also responsible for an earthquake in 1931.[10]

Damage

The Gates of Ganja at the Gelati Monastery

Mkhitar Gosh, an Armenian scholar and writer, quoted Job 9:6 and Psalm 103:32 from the Holy Bible to describe the earthquake.[12] He wrote of tremendous damage in the P'ar'isos and Xach'e'n districts of Syunik. The city of Ganzak was also devastated, leaving many of its residents buried under ruins. Many structures, including monasteries and churches, castles and villages in the mountainous region, were totally destroyed.[13] Strong shaking triggered massive landslides off the sides of mountains and canyons in the Caucasus Mountains region. Parts of Kapaz Mount collapsed, and the resulting landslide blocked the Kürəkçay River, forming Lake Göygöl.[14] Another six lakes formed, including Maral-gol and Lake Ağgöl.[15]

The number of people who died in the mountains is not known, described as "incalculable".[13] Estimates of the death toll range between 230,000 and 300,000, making it one of the deadliest earthquakes in history.[9] Among the dead were two sons of the ruler of the Seljuk Empire, Qara Sonqor.[16] The death toll figure remains controversial with some authors stating it is an exaggeration considering the population of the area at the time of the disaster.[17] Others argued that this was a conflation of information about the 1138 Aleppo and 1137 Jazira earthquakes.[1]

Aftermath

King Demetrius I of Georgia took advantage of the earthquake and looted the city. Troops stole many artifacts and prized items from the city, including the Ancient Gates of Ganja, which were treated as a trophy.[18][19] The city was reconstructed by Qara Sonqor, and it again began to flourish.[20]

See also

References

  1. ^ a b Ambraseys, N. (2004), "The 12th century seismic paroxysm in the Middle East: a historical perspective" (PDF), Annals of Geophysics, 47 (2–3), National Institute of Geophysics and Volcanology: 743, archived (PDF) from the original on 2020-08-21, retrieved 2021-06-23
  2. ^ a b Ulomov, V.I.; Medvedeva, N.S. (2014). "Специализированный каталог землетрясений для задач общего сейсмического районирования территории Российской Федерации" [Specialized catalog of earthquakes for the purpose of general seismic zoning of the territory of the Russian Federation] (PDF). O.Y. Smidt Institute of Physics of the Earth, Russian Academy of Sciences. Archived (PDF) from the original on 2023-04-04. Retrieved 2021-06-04.
  3. ^ "Most Destructive Known Earthquakes on Record in the World". United States Geological Survey. Archived from the original on 2009-09-01. Retrieved 2022-04-22.
  4. ^ Alik Ismail-Zadeh; Shota Adamia; Aleksandre Chabukiani; Tamaz Chelidze; Sierd Cloetingh; Michael Floyd; Alexander Gorshkov; Alexei Gvishiani; Tahir Ismail-Zadeh; Mikhail K. Kaban; Fakhraddin Kadirov; Jon Karapetyan; Talat Kangarli; Jemal Kiria; Ivan Koulakov; Jon Mosar; Tea Mumladze; Birgit Müller; Alexander Soloviev (2020). "Geodynamics, seismicity, and seismic hazards of the Caucasus" (PDF). Earth-Science Reviews. 207 (103222). Elsevier: 103222. Bibcode:2020ESRv..20703222I. doi:10.1016/j.earscirev.2020.103222. hdl:1874/408462. S2CID 219925399.
  5. ^ Bochud, Martin (2011-10-25). Tectonics of the Eastern Greater Caucasus in Azerbaijan (PDF) (Dr. rer. nat. thesis). Switzerland: University of Fribourg. Archived (PDF) from the original on 2022-03-04. Retrieved 2022-03-04.
  6. ^ Musson R.M.W. (2014). "Great Earthquakes". Encyclopedia of Solid Earth Geophysics. Encyclopedia of Earth Sciences Series. Netherlands: Springer, Dordrecht. pp. 561–568. doi:10.1007/978-90-481-8702-7_7. ISBN 978-90-481-8702-7. Archived from the original on 21 February 2023. Retrieved 23 June 2021.
  7. ^ Inessa Vorobieva; Alik Ismail-Zadeh; Alexander Gorshkov (2019). "Nonlinear dynamics of crustal blocks and faults and earthquake occurrences in the Transcaucasian region" (PDF). Physics of the Earth and Planetary Interiors. 297 (106320). Elsevier: 106320. Bibcode:2019PEPI..29706320V. doi:10.1016/j.pepi.2019.106320. S2CID 210621325. Archived (PDF) from the original on 2022-08-10. Retrieved 2022-03-04.
  8. ^ Guidoboni, E.; Ferrari, G.; Comastria., A.; Tarabusi, G.; Sgattoni, G.; Valensise, G. (2018). "Catalogue of Strong Earthquakes in Italy 461 B.C. – 1997 and Mediterranean Area 760 B.C. – 1500". National Institute of Geophysics and Volcanology (INGV). doi:10.6092/ingv.it-cfti5. Archived from the original on 4 June 2021. Retrieved 4 June 2021.
  9. ^ a b National Geophysical Data Center (1972). "Significant Earthquake Information AZERBAIJAN: GYZNDZHA". National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information. doi:10.7289/V5TD9V7K. Archived from the original on 30 September 2022. Retrieved 4 June 2021. {{cite journal}}: Cite journal requires |journal= (help)
  10. ^ a b Alice O. Matossian; Hayk Baghdasaryan; Ara Avagyan; Hayk Igityan; Mikayel Gevorgyan; Hans-Balder Havenith (2020). "A New Landslide Inventory for the Armenian Lesser Caucasus: Slope Failure Morphologies and Seismotectonic Influences on Large Landslides". Geosciences. 10 (3): 111. Bibcode:2020Geosc..10..111M. doi:10.3390/geosciences10030111. hdl:1854/LU-8655179.
  11. ^ J.-F. Ritz; A. Avagyan; M. Mkrtchyan; H. Nazari; P.-H. Blard; A. Karakhanian; H. Philip; S. Balescu; S. Mahan; S. Huot; P. Münch; M. Lamothe (2016). "Active tectonics within the NW and SE extensions of the Pambak-Sevan-Syunik fault: Implications for the present geodynamics of Armenia" (PDF). Quaternary International. 395. Elsevier: 61–78. Bibcode:2016QuInt.395...61R. doi:10.1016/j.quaint.2015.05.021. Archived (PDF) from the original on 2022-03-04. Retrieved 2022-03-04.
  12. ^ Manuel Berberian (2014). Earthquakes and Coseismic Surface Faulting on the Iranian Plateau. Elsevier. p. 63. ISBN 9780444632920.
  13. ^ a b Mkhitar Gosh's Colophon (PDF). Archived (PDF) from the original on 10 January 2023. Retrieved 12 July 2021.
  14. ^ Vorobieva, I.; Ismail-Zadeh, A.; Gorshkov, A. (2019). "Nonlinear dynamics of crustal blocks and faults and earthquake occurrences in the Transcaucasian region". Physics of the Earth and Planetary Interiors. 297: 106320. Bibcode:2019PEPI..29706320V. doi:10.1016/j.pepi.2019.106320. S2CID 210621325. Archived from the original on 2022-09-30. Retrieved 2021-11-15.
  15. ^ "History of Ganja". ganca.net. Archived from the original on 23 October 2020. Retrieved 5 March 2022.
  16. ^ Ибн ал-Асир. Тарих-ал-камиль. О победе султана Махмуда над курджами. Перевод П. К. Жузе. Текст воспроизведен по изданию: Материалы по истории Азербайджана из Тарих-ал-камиль (полного свода истории) Ибн-ал-Асира. Баку. АзФан. 1940.
  17. ^ Guidoboni, Emanuela; Comastri, Alberto (2005). Catalogue of earthquakes and tsunamis in the Mediterranean area from the 11th to the 15th century. National Institute of Geophysics and Volcanology (Roma).
  18. ^ "Распахнутся снова ворота Гянджи". Trend.Az (in Russian). 6 April 2007. Archived from the original on 6 November 2019. Retrieved 4 March 2022.
  19. ^ "Гянджинские ворота". kataloq.gomap.az (in Russian). Archived from the original on 30 September 2022. Retrieved 4 March 2022.
  20. ^ Edmund Bosworth (2000), Ganja (Fascicle), vol. X, Encyclopædia Iranica, pp. 282–283, archived from the original on 10 January 2012, retrieved 4 March 2022