Geosciences Research

Download PDF (2400.5 KB) PP. 138 - 150 Pub. Date: May 15, 2017

DOI: 10.22606/gr.2017.22007

• Ahmed Badawy^*
  Seismology Dept., National Research Institute of Astronomy and Geophysics, 11421-Helwan, Egypt
• Sh. Ali
  
  Seismology Dept., National Research Institute of Astronomy and Geophysics, 11421-Helwan, Egypt
• A. El-Werr
  
  Geophysics Dept., Faculty of Sciences, Ain Shams University, Cairo, Egypt

The source characterizations of five small felt earthquakes have been investigated using local seismograms of the Egyptian National Seismological Network (ENSN), Egypt. The studied earthquakes are located at three inland dislocations namely: Dahshour, southeast Beni-Suef and Cairo-Suez district. Throughout the analysis, Empirical Green’s Function (EGF) deconvolution technique has been applied. The records of an appropriate aftershock are taken as the EGF and are used to deconvolve the mainshock seismograms, thus obtaining a Relative Source Time Function (RSTF) at each station. The deconvolution is performed using P waves in frequency domain. From the time-domain analysis of the RSTF, the resulting source time functions indicate a complex rupture process for the strike-slip events (11 October, 1999 and 08 November, 2006)) and simple rupture process for the dip-slip events (28 December, 1999; 12 June 2001 and 17 December, 2001). The azimuthally dependencies of the RSTF pulse amplitudes and widths are used to estimate rupture velocity and rupture directivity. We found that the rupture directions are tending to propagate toward the north and NNW.

Source characterization, small inland earthquakes, Empirical Green’s Function, relative source time function, tectonic implications.

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