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Geosciences Journal

, Volume 5, Issue 2, pp 165–171 | Cite as

Focal mechanism determination based on the polarity and SV-P amplitude ratio in the Kalabsha area, Aswan, Egypt

  • Haggag Hamed Mohamed
  • Tae-Seob Kang
  • Chang-Eob Baag
Article

Abstract

Focal orientations are presented for small earth-quakes of the four different local seismic zones (zone A, zone B, zone C and zone D) in the Kalabsha area, Aswan, Egypt. These earthquakes (1.2≤M<3, and depth 1.5-23km) were monitored by the Aswan Telemetered Network between November 1995 and November 1997. Three or four single-event focal mechanisms and one composite event focal mechanism were determined for each zone. One composite focal mechanism for all events of the zones A, B, and C (10 earthquakes) was obtained. Both P-wave polarities and SV/P amplitude ratios were used to determine the focal mechanisms in the study area. The focal mechanism solutions in the four seismic zones show that they are almost characterized by strike-slip faults with two types of motion, right lateral along ENE-WSW faults and left lateral motion along NNW-SSE faults. The orientations of the compressional and tensional stresses prevailing in the area have the directions of ESE-WNW and NNE-SSW, respectively. It is found that there is no significant change in either the direction of prevailing stresses or the senses of motion along the preexisting faults in the area.

Key words

focal mechanism P-wave polarity SV/P amplitude ratio Kalabsha area strike-slip motion 

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Copyright information

© Springer 2001

Authors and Affiliations

  • Haggag Hamed Mohamed
    • 1
  • Tae-Seob Kang
    • 2
  • Chang-Eob Baag
    • 2
  1. 1.National Research Institute of Astronomy and GeophysicsCairoEgypt
  2. 2.School of Earth and Environmental SciencesSeoul National UniversitySeoulKorea

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