Reinvestigation of the 1978 Gilf El Kebir earthquake, Egypt

Figures & data

Figure 1. Location map for Gilf El Kebir studied area with seismicity M_L > 4 from 1970 to 2022.

Figure 2. a) geological map modeified after Egyptian Mineral Resources Authority (EMRA) 2008 b) focal mechanism solution of earthquakes in the studied and adjacent areas, Table 1 and in the Gebco (2019) digitial elevation model base map (Tozer et al. 2019).

Table 1. Focal mechanism solutions used in this study and adjacent areas for earthquakes with magnitude (ML)>4.6.

N	Long.	Lat.	Date/Origin time	Plane 1			Plane 2			P-axis		T-axis		D. km	ML	References
				Strike	dip	Rake	Strike	dip	Rake	Trend	Plunge	Trend	Plunge
1	26.20	24.00	9 December 1978 /07:12:52	323.65	74.00	−19.66	58.70	72.94	−193.00	281.00	23.23	11.38	00.72	7.0	5.3	In this study
				322.82	77.80	−21.99	57.70	68.53	−166.00	278.77	24.00	11.55	06.28
				327.60	75.97	−20.90	62.00	69.74	−165.00	284.00	16.12	24.00	04.20
				318.00	75.97	−20.91	53.28	69.74	−165.06	274.58	24.58	06.52	04.23
2	32.28	23.88	14 November 1981 /09:05:34	146.00	72.00	−15.00	241	76	−162	104	23	13.00	2.00	15	5.8	(CMT HARVERD, 2012)
3	34.52	25.25	2 July 1984 /01:46:59	131.21	71.78	−29.12	230.7	62.43	−159.60	87.81	28.88	181.94	07.44	9	5.1	(Hussein et al. 2011)
4	32.84	24.00	07 November, 2010 /09:54:34	256	76	−154	160	65	−15	120.84	27.69	26.44	07.64	5	4.6	(Saadalla et al. 2020)
5	28.63	22.88	19 February 2021 /08:40:00	350.0	56.47	−13.95	87.81	78.40	−145.68	314.18	32.19	214.89	14.38	8.0	4.6	In this study
				350.52	58.30	−12.99	87.43	78.97	−147.63	313.58	30.45	215.36	13.67
				354.07	58.30	−12.99	90.9	78.97	−147.63	317.13	30.45	218.91	13.67

Figure 3. a). 9 December 1978 earthquake, M5.3, b). 19 February 2021 earthquake, M4.6.

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