Attenuation of coda waves in the Dead Sea region

Coda waves of local small earthquakes in the Dead Sea region, part of the Jordan rift structure, show frequency invariant codas, that is Qc = Q0(f/f0)n, with Q0 = 65 ± 5, f0 = 1 Hz and n = 1.05 ± 0.04 for hypocentral distances between 10 and 55 km, and lapse times less than 60 sec. This justifies, for example, the use of part of the coda for relative site response studies. Lacking direct Qβ measurements, Qc might be considered as a first approximation of Qβ for the region. For short hypocentral distances, r < 20 km, rapidly increasing Qc with lapse time, t, has been observed.