Crustal structure of Tushka region, Abu-Simbel, Egypt, inferred from spectral ratios of P waves of local earthquakes

• Autorzy: Gharib A.
• Języki publikacji: EN

Abstrakty

EN

The crustal structure of North Abu-Simbel area was studied using spectral ra-tios of short-period P waves. Three-component short period seismograms from the Masmas seismic station of the Egyptian National Seismic Network Stations were used. The Thomson–Haskell matrix formulation was applied for linearly elastic, homogeneous crustal layers. The obtained model suggests that the crust under the study region consists of a thin (0.8 km) superficial top layer with a P-wave velocity of 3.8š0.7 km/s and three distinct layers with a mean P-wave velocity of 6.6 km/s, overlaying the upper mantle with a P-wave velocity of 8.3 km/s (fixed). The results were obtained for 14 different earthquakes. The P-wave velocities of the three layers are: 5.8š0.6 km/s, 6.5š0.4 km/s and 7.2š0.3 km/s. The total depth to the Moho interface is 32š2 km. The crustal velocity model estimated using observations is relatively simple, being characterized by smooth velocity variations through the middle and lower crust and normal crustal thickness. The resultant crustal model is consistent with the model obtained from previous deep seismic soundings along the northern part of Aswan lake zone.

Słowa kluczowe

EN

Tushka region; P-wave spectral ratios,; cross-correlation; crustal structure model.

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2006
• Tom: Vol. 54, no. 4
• Strony: 361--377

Twórcy

autor

Gharib A.

• National Research Institute of Astronomy and Geophysics (NRIAG) 11421-Helwan, Cairo, Egypt,

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