Intrinsic Qp seismic attenuation from the rise time of microearthquakes: a local scale application at Rio-Antirrio, Western Greece.

We determine the attenuation structure of a three-dimensional medium based on first pulse-width measurements from microearthquake data. Ninety-five microearthquakes from a seventy stations local network were considered in this study. Measurements of the first half cycle of the wave, the so-called rise time τ were carried out on high quality velocity seismograms and inverted to estimate the P-waves intrinsic quality factor Qp. The results of this investigation indicate that first pulse width data from a local microearthquake network permit retrieval with sufficient accuracy of the heterogeneous Qp structure. The inferred attenuation variability corresponds to the known geological formations in the region. [ABSTRACT FROM AUTHOR]