The attenuation mechanism of seismic waves in northwestern Himalayas.

We analysed local earthquake waveforms recorded on a broad-band seismic network in northwestern Himalayas to compute the intrinsic and scattered attenuation parameters from coda waves. Similar to other tectonically active and heterogeneous regions, attenuation-frequency relation for western Himalaya is where is the coda Q parameter. Intrinsic and scattering attenuations was separated using and direct S-wave Q data . It is observed that estimated is close to and both of them are much larger than suggesting that coda decay is predominantly caused by intrinsic attenuation. At higher frequencies, both the attenuation parameters and, are similar indicating that coda is predominantly composed of back-scattered S waves at these frequencies. [ABSTRACT FROM AUTHOR]