PRELIMINARY SHEAR Q STRUCTURE IN THE MEDITERRANEAN-SEA FROM RAYLEIGH-WAVE OBSERVATIONS

Fundamental-mode Rayleigh wave attenuation coefficients have been obtained for the Mediterranean Sea using the two-station method applied to seismograph stations located in the coastal regions of Spain and Israel. The average attenuation coefficients vary between 7.36 10(-4)km(-1), at a 16 s period, to 0.76 10(-4)km(-1) at a 70 s period. The associated Rayleigh wave anelastic factors range from 42 to 157. The above results indicate a relatively highly attenuating region. Inversion methods applied to the determined Rayleigh wave attenuation coefficients indicate that a strong and well-developed shear Q structure seems to be located under the Mediterranean Sea.