Q-values for P and S Waves in Southern Sinai and Gulf of Suez Region, Egypt

Аннотация

The quality agents for P- and S-waves (Q_p and Q_s) were estimated for earthquakes that recorded by nine seismic stations (DHA, NUB, TR1, TR2, KAT, SH2, GRB, HRG and SFG) from the Egyptian National Seismological Network (ENSN). These stations are located at southern Sinai and northern Red Sea coast region. For Q-values estimation, one station spectral rate method was applied and the spectral amplitude rates have been calculated between 2‒20 Hz for this aim. The obtained Q-values prove that Q_p and Q_s increase as a follower of frequency according to the relation Q = Q₀f ⁿ. By averaging Q-values which were calculated at all nine stations the median attenuation relations for Q_p and Q_s were obtained as: Q_p = (13.15 ± 0.76) f ^0.95±0.19 and Q_s = (20.05± 0.79)f ^1.03±0.04. These relations are helpful for respect of origin parameters of earthquakes and emulation of earthquake strong ground motions. The Q_s/Q_p ratio for KAT station is less than 1 at lower frequencies, whereas at HRG and SH2 stations Q_s/Q_p ratios are greater than 1.