【摘要】 使用河北省数字地震遥测台网25个台的259条波形记录资料,采用三段几何衰减模型,通过反演得到华北中北部地区剪切波的衰减模型和介质的品质固子Q（f）值,Q（f）=420.8f^0.384。研究发现,华北中北部地区的Q值与广东地区很接近,而与其它地区差异较大。更多还原

【Abstract】 Based on 259 horizontal-component digital seismograms recorded on 25 stations of HebeiTelemetered Network, the attenuation model and medium quality factor Q（f）=420. 8f^0.384 of S-wave inCentral and North area of North China are obtained by using a trilinear geometrical spreading model andGA. It is shown that Q（f） in Central and North area of NorthChina is similar to that in Guangdong. Trilinear geometrical spreading model of NorthChina indicates that at a distance less than 50 km, cor-responding to attenuation of the direct wavel amplitudes decay slightly and more rapidly than 1/R. Be-tween 50 and 83 km, where the direct wave is joined by SmS, spectral amplitudes are approximately con-stant. Beyond 83 km, corresponding to the Lg phase, amplitudes decay at a rate that is consistent withR^-0.5. The result shows that postcritical reflections from the Moho discontinuity play an important role indetermining the shape of the attenuation curve.更多还原