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用云南腾冲火山地区观测的地震数字化记录进行了尾波和剪切波的衰减测量。用AkiandChouet和Sato单次散射模型获得 5 2秒和 18秒流逝时间尾波的品质因子分别为Qc (f) =5 7×f- 0 94和Qc (f) =2 6×f- 0 95 ,表明地壳上部和地壳上地幔的地震波衰减频率变化率一致。两者均未显示出活火山地区尾波衰减的异常特征。尾波掠过空间椭球的平均半轴 ,前者约为 80km ,大大超出了腾冲火山分布的地理范围 ,后者约为 30km ,在腾冲火山分布的地理范围之内。用尾波规一双台S波振幅比法进一步缩小所用地震波掠过的空间 ,最后获得了S波随频率的衰减有类似于前人报导的活火山地区尾波频率衰减的特征 :相对于低频 (1 5～ 6Hz) ,高频 (6～2 0Hz)的Q- 1s 变化很小。从地表位置看 ,腾冲最年青的全新世的马鞍山和老龟坡火山就在S波掠过范围内 ,打鹰山火山也在近旁。这一结果表明在这三座火山体之下存在低速高衰减体。火山或处于休眠状态 ,或在消亡过程之中。
The coseismic and shear wave attenuation measurements were made using the digitized records of earthquakes observed in the volcano Tengchong, Yunnan. The quality factors of the wake wave of 52 seconds and 18 seconds were obtained with the AkiandChouet and Sato single-scattering models as follows: Qc (f) = 57 × f-0 94 and Qc (f) = 26 × f-0 95, It shows that the rate of change of seismic wave attenuation frequency in the upper crust and upper crust upper mantle is consistent. Neither show the abnormal characteristics of coda attenuation in the active volcano area. The average of the coda wave passing over the ellipsoid of the space is about 80 km, far beyond the geographic range of the Tengchong volcano, which is about 30 km within the geographic range of the Tengchong volcano. Finally, the attenuation of S-wave with frequency is similar to that of the coda wave attenuation in the active volcano region reported by the predecessor. Compared with the low-frequency 1 5 ~ 6Hz), high frequency (6 ~ 20Hz) Q-1s change is small. From the surface location, the youngest Holocene Ma Tanshan and La Kamepo volcanoes in Tengchong are within the range of S waves, and the Eagles are also nearby. This result shows that there are low-velocity and high-attenuation bodies beneath the three volcanoes. Volcano or in dormancy, or in the demise process.