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The characteristic of seismic coda wave attenuation in Yunnan area in 7 frequency-bands range from 1 Hz to 20 Hz was estimated by using the local earthquake′s waveform data recorded from 22 Yunnan digital seismic stations. Coda attenuation Qc ?1 of each station was firstly calculated by single scattering method. Then, mean free path Le and seismic albedo B0 of each station were calculated, and scattering attenuation Qs ?1 and intrinsic attenuation 1iQ ? were separated from total attenuation Qt ?1 by multiple lapse time window analysis based on the multiple scattering model in uniform random isotropic scattering medium. The attenuating characteristics in Yunnan show that most value of Le are in 10~30 km, with maximal within 2~6 Hz; B0 are about 0.5 at 1~2 Hz, but less than 0.5 at other frequency-bands, which means Qi ?1 is comparable with Qs ?1 at 1~2 Hz, and after 1~2 Hz, Qi ?1 is greater than Qs 1 and dominates the attenuation process. Qc 1 is close to Qi 1 at other frequency bands except 1~2 Hz. Results show that Q?1 especially Qs 1 varies spatially, Q1 in eastern Yunnan zone is a bit higher than in north-western Yunnan zone; northwestern Yunnan zone higher than southwestern Yunnan zone. Comparing with other results in global, Qs 1 in Yunnan is lower than the global average value among these results, Qi 1 is higher than the global average value, and Qt 1 lies the middle among these results.
The characteristic of seismic coda wave attenuation in Yunnan area in 7 frequency-bands range from 1 Hz to 20 Hz was estimated by using the local earthquake’s waveform data recorded from 22 Yunnan digital seismic stations. Coda attenuation Qc? 1 of each station was The mean free path Le and seismic albedo B0 of each station were calculated, and scattering attenuation Qs? 1 and intrinsic attenuation 1iQ? were separated from total attenuation Qt? 1 by multiple lapse time window analysis based on the multiple scattering model in uniform random isotropic scattering medium. The attenuation characteristics in Yunnan show that the most value of Le are in 10 ~ 30 km, with maximal within 2 ~ 6 Hz; B0 are about 0.5 at 1 ~ 2 Hz, but less than than 0.5 at other frequency-bands, which means Qi? 1 is comparable with Qs? 1 at 1 ~ 2 Hz, and after 1 ~ 2 Hz, Qi? 1 is greater than Qs 1 and dominates the attenuation process. Qc 1 is close to Qi 1 at other frequency bands except 1 to 2 Hz. Results show that Q? 1 especially Qs 1 varies spatially, Q1 in eastern Yunnan zone is a bit higher than in north-western Yunnan zone; northwestern Yunnan zone higher than southwestern Yunnan zone. Comparing with other results in global , Qs 1 in Yunnan is lower than the global average value among these results, Qi 1 is higher than the global average value, and Qt 1 lies the middle among these results.