Temporal and three dimensional spatial analysis of seismicity in the Lake Aswan area, Egypt

• Autorzy: Awad H. , Mekkawi M. , Hassib G. , Elbohoty M.
• Języki publikacji: EN

Abstrakty

EN

On 28 September 2004 an earthquake swarm with the largest event of magnitude 4.2 occurred in the epicentral area of the 1981 Lake Aswan earthquake (M = 5.7), the latest manifestation of seismicity in the area. The swarm is located in a shallow zone along the Rawraw trend, 8 km north of the Kalabsha fault, the main active fault in the Lake Aswan area. The Kalabsha fault is charac-terized by the presence of shallow and deep seismic zones. The shallow earth-quakes have focal depths smaller than 10 km. The sources of deep earthquakes are located at a depth between 14 and 30 km. Characteristics of seismicity observed from 1982 to 2004 along the Kalab-sha and Rawraw faults and the correlation between the temporal variation of seismicity and the water level changes in the Lake Aswan are analysed. The re-sults indicate that the earthquakes in the deep seismic zone along the Kalabsha fault are characterized by a relatively low b-values and show greater degree of clustering than the shallow events. The shallow earthquakes along both the Kalabsha fault and the Rawraw trend are better correlated with the water level changes in the Lake Aswan than the deep events. Thus, the shallow events may be classified as seismicity induced by the water reservoir. Migration of seismic sources along these faults toward the shallow part of the crust is also apparent.

Słowa kluczowe

EN

seismicity of the Lake Aswan; faults; shallow earthquakes

• Wydawca: Instytut Geofizyki PAN
• Czasopismo: Acta Geophysica Polonica
• Rocznik: 2005
• Tom: Vol. 53, nr 2
• Strony: 153--165
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Awad H.

• National Research Institute of Astronomy and Geophysics, 11-421 Helwan, Cairo, Egypt

autor

Mekkawi M.

• National Research Institute of Astronomy and Geophysics, 11-421 Helwan, Cairo, Egypt

autor

Hassib G.

• National Research Institute of Astronomy and Geophysics, 11-421 Helwan, Cairo, Egypt

autor

Elbohoty M.

• National Research Institute of Astronomy and Geophysics, 11-421 Helwan, Cairo, Egypt

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