Liang G.-J.,Volcanic Observatory of Longgang |
Li Z.-W.,Volcanic Observatory of Longgang |
Zheng S.-F.,Volcanic Observatory of Longgang |
Liu J.-Q.,China Earthquake Administration |
And 2 more authors.
Dizhen Dizhi | Year: 2011
According to Sato (1977) single scattering model and using 41 earthquakes with ML1.6 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 10km, 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(0.845 9±0.164 2),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 Qo 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 volca For the lower coda Qovalue,we interpret the strong attenuation of coda waves near the Longgang volcano is possibly related to high temperature medium caused by magma chambers.