基于sato单次散射模型,利用2007年5月至2010年2月龙岗火山测震台网记录到的发生在火山区及邻近地区内的41次Mt.≥1.6地震的波形资料,计算了龙岗火山区的尾波Q值,得出尾波Q值与频率的关系为Q(f)=(42.65±7.53)f(0.845 9+0.164 2),具有以低Q值高η值为特征的火山构造活跃地区的尾波性质.火山区尾波Q值的空间分布显示,金龙顶子火山附近的金川台尾波Q0值为31.98.明显低于其它台站.结合深地震探测和垂直形变资料成果,佐证了龙岗火山岩浆囊的位置可能在金龙顶子火山附近.%According to Sato( 1977) single scattering model and using 41 earthquakes with ML ≥ 1. 6 in the Longgang volcano and the nearby regions recorded by Longgang volcano digital seismic network from 2007 to February 2010, the coda Q value in the Longgang volcanic region was determined. All of events used in this paper occurred at depths from 6 to 1Okm,with the epicentral distances less than 75km. The results show that the coda Q has a dependence with frequency as Q (f) = (41. 65±11. 74)f(O.8459±0.1642) ,which is characteristic of coda in active volcanic regions as low Q value and high η value. Compared to other volcanic areas in the world , the average Qc of the Longgang volcanic area is obviously lower. Distribution of coda Q value on Longgang volcano shows that coda Q0 value at Jinchuan seismic station near Jinlongdingzi volcano is 31. 98 , significantly lower than other stations',which,in combination with the deep seismic sounding data and vertical deformation data,proves that the magma chambers probably locate in the vicinity of Jinlongdingzi volcano. For the lower coda Q0 value ,we interpret the strong attenuation of coda waves near the Longgang volcano is possibly related to high temperature medium caused by magma chambers.
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