traces of vertical components from shallow earthquakes recorded by 10 CDSN (Chinese Digital Seismographic Network) stations and 5 GSN (Global Seismographic Network) stations were collected to study the attenuation cha...traces of vertical components from shallow earthquakes recorded by 10 CDSN (Chinese Digital Seismographic Network) stations and 5 GSN (Global Seismographic Network) stations were collected to study the attenuation characteristics of Lg coda in the Chinese continent and its adjacent regions. The records were processed first using the stack spectral ratio method to obtain the average values of Q0 (Q at 1Hz) and h, the frequency dependence, of Lg coda in the ellipses corresponding to the paths. The back-projection technique was then employed to obtain the tomographic maps of Q0 and h values, and the distribution of their errors. Results indicate that in the studied area Q0 varies between 200 and 500. The lowest value of Q0 exists in the Yun-nan-Tibetan region, while the highest value of Q0 occurs in the southern edge of Siberian platform. h varies between 0.3 and 0.8. For most part of the studied area h varies inversely with Q0.展开更多
基金This study is supported by the National Natural Science Foundation of China (Grant No. 49974012) and the Natural Science Foundation of Yunnan Province (Grant No. 98D003R).
文摘traces of vertical components from shallow earthquakes recorded by 10 CDSN (Chinese Digital Seismographic Network) stations and 5 GSN (Global Seismographic Network) stations were collected to study the attenuation characteristics of Lg coda in the Chinese continent and its adjacent regions. The records were processed first using the stack spectral ratio method to obtain the average values of Q0 (Q at 1Hz) and h, the frequency dependence, of Lg coda in the ellipses corresponding to the paths. The back-projection technique was then employed to obtain the tomographic maps of Q0 and h values, and the distribution of their errors. Results indicate that in the studied area Q0 varies between 200 and 500. The lowest value of Q0 exists in the Yun-nan-Tibetan region, while the highest value of Q0 occurs in the southern edge of Siberian platform. h varies between 0.3 and 0.8. For most part of the studied area h varies inversely with Q0.
