Lg-waves propagate over long distances in the northern part of Africa and are recorded on the seismic station located close to Abeche (Chad). We have applied the well-known coda analysis method developed by Aki and Ch...Lg-waves propagate over long distances in the northern part of Africa and are recorded on the seismic station located close to Abeche (Chad). We have applied the well-known coda analysis method developed by Aki and Chouet [1] to study the Lg-wave anelastic attenuation in this area. We found a frequency dependence: Q( f ) = (650±34) f <sup>(0.77±0.2)</sup>. This result shows an average value of Q0 (Q0 ≈ 650) for earthquakes occurred in tectonic areas as the East African Rift system, Turkey, Greece and Red Sea. The higher value of Q0 (Q0 ≈ 800) is obtained for the event occurred in the middle of the stable plate close to the Tamanrasset (TAM) station in Algeria.展开更多
文摘Lg-waves propagate over long distances in the northern part of Africa and are recorded on the seismic station located close to Abeche (Chad). We have applied the well-known coda analysis method developed by Aki and Chouet [1] to study the Lg-wave anelastic attenuation in this area. We found a frequency dependence: Q( f ) = (650±34) f <sup>(0.77±0.2)</sup>. This result shows an average value of Q0 (Q0 ≈ 650) for earthquakes occurred in tectonic areas as the East African Rift system, Turkey, Greece and Red Sea. The higher value of Q0 (Q0 ≈ 800) is obtained for the event occurred in the middle of the stable plate close to the Tamanrasset (TAM) station in Algeria.
