1992 Cairo earthquake

Geology

Cairo sits within a diffuse zone of faulting that transfers extension from the Gulf of Suez Rift to the Manzala rift beneath the Nile Delta.

Damage

More than 129,000 residential buildings and houses were affected by the earthquake across 17 of Egypt’s 27 governorates, disproportionately affecting heavily populated governorates near to the epicentre, with Giza, where the epicentre was, seeing over two fifths of the damage.

Over 12,000 residential buildings and houses (12%) collapsed or were so heavily damaged, they were identified to be demolished, while a further 28,000 buildings (25%), required significant repairs or partial demolition (usually of a floor or more), and the remaining two thirds were found to need minor repair. Some 216 mosques and 350 schools were badly damaged.

Around 40,000 of the affected buildings were in the capital, Cairo, representing over one third of all buildings. The areas of greatest damage were in the historic neighbourhoods of Historic Cairo, Old Cairo and Boulaq. Damage was reported to have affected 212 out of a total of 560 historical monuments. Most of the severe damage was confined to older masonry structures and particularly those built of adobe. The exception was a modern reinforced concrete building in Heliopolis, killing 79 people. Fortunately, many of the inhabitants were outside of the building at the time of the event. It was later revealed that many additional stories were added to the building illegally and the ground floor/basement had been opened up to accommodate community amenities, including a laundry.

The villages of Giza, were some of the worse hit as they were very close to the epicentre, where 5292 houses collapsed or were damaged beyond repair, and 12,700 needed significant repair, while three villages were almost entirely levelled in Markaz Al-Ayyat. Liquefaction was reported from areas near the epicenter.

The third most affected governorate was Fayoum, where villages in its north-east were also close to the epicentre, especially in Markaz Tamiya where heavy damage was sustained in 5135 houses in the villages of Al-Rawda, Manshiyat Al-Gamal, Qasr Rashwan and Fanous.

The high number of deaths and injuries (561 and 12,392 respectively) was partly due to the amount of panic caused by the earthquake in Cairo itself. A large block fell from the Great Pyramid of Giza.

Earthquake characteristics

The earthquake was felt throughout most of northern Egypt, in Alexandria, Port Said and as far south as Asyut, and in southern Israel. The calculated focal mechanism suggests that this event originated on a WNW-ESE or W-E trending normal fault with a small strike-slip component. The aftershocks extended about 11 km to the south-east of the main shock epicentre, indicating unidirectional rupture propagation. The estimated fault rupture length was also 11 km. The earthquake consisted of two sub-events, the second located about 27 km south-east of the first.

Response

The government was criticized for not doing much to respond. On the other hand, Islamic fundamentalist groups such as the Muslim Brotherhood stepped in to provide aid.

References

References

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2. (11 March 2010). "Modelling of seismic hazard at the northeastern part of greater Cairo metropolitan area, Egypt". Journal of Geophysics and Engineering.
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4. (1 September 2009). "Stochastic ground motion simulation of the 12 October 1992 Dahshour earthquake". Acta Geophysica.
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6. (1 November 1992). "رئيس الوزراء فى حديث"للاهرام"حول قضايا الساعه:شقه جديده بالمرافق خلال هذا الشهر لكل من انهار مسكنه". Al-Ahram.
7. (6 September 2023}}{{Creative Commons text attribution notice). "Mapping the Fallout of the 1992 Dahshur (Egypt) Earthquake".
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9. (October 2005). "The Red Sea and Gulf of Aden Basins". Journal of African Earth Sciences.
10. "NGDC page on the Cairo earthquake".
11. "NGDC page on the Cairo earthquake".
12. (1993). "NCEER-93-0016: Reconnaissance of Damage to Historic Monuments in Cairo, Egypt Following the October 12, 1992 Dahshur Earthquake".
13. [https://www.jstor.org/stable/40574029 "Earthquake Vulnerability in the Middle East"] DEGG, MARTIN, and JACQUELINE HOMAN. ''Geography'', vol. 90, no. 1, 2005, pp. 54–66. [[JSTOR]]. Accessed 16 July 2021.
14. (1 January 2009). "Estimation of Ground Motion at Damaged Area During 1992 Cairo Earthquake Using Empirical Green's Functions". Seismological Research Letters.
15. Hussein, H.M.. (1999). "Source process of the October 12, 1992 Cairo earthquake". Annali di Geofisica.
16. Hussein, H.M.. (1996). "The October 12, 1992 Cairo earthquake a complex multiple shock". Bulletin of the International Institute of Seismology and Earthquake Engineering.
17. "Muslim Groups Take Lead in Cairo Quake Relief : Egypt: Mosques house and feed the homeless. Disappointment in government assistance is expressed.".