Regional variation of attenuation and travel time in China from analysis of multiple-ScS phases

Long-period multiple ScS waveforms from intermediate- and deep-focus earthquakes surrounding China, recorded by the Chinese Digital Seismograph Network, are used to estimate the multiple-ScS attenuation operator and differential travel times using both frequency (phase equalization and stacking) and time domain (waveform inversion) techniques. Theoretical considerations, augmented by synthetic testing, indicate that for continental regions the frequency domain approach yields a more stable estimate of whole mantle attenuation (Q_ScS) that the time domain approach, which is better for whole mantle travel time (τ_ScS). When teamed together, the two afford unprecedented success with continental paths. -from Authors