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宽频带地震记录可以表示为震源时间函数、传播算子和散射／衰减算子的褶积．在传播算子与频率无关、地震波的散射和衰减效应可以用一个以Ｑ－１＝Ｑ－１１＋（Ｑ２ω）－１的方式随频率变化的Ｑ值来表示的情况下，通过位移谱的组合，可以直接估计震源谱；而Ｑ值对地震图的影响，在频谱的组合中被自动消去．用这种算法处理了１９８８年中国云南省澜沧－耿马地震５次余震的近震源宽频带地震记录．对ＭＬ＝３．０和ＭＬ＝３．５余震的处理结果表明，由不同台站上的宽频带地震记录，可以得到相同的高频衰减趋势．对ＭＳ＝６．７的强余震处理结果表明，可以从不同的地震台站上得到相同的震源参数，所估计的参数值也与用经验格林函数法得到的结果相吻合．这些余震震源谱的高频部分呈现出典型的ｆ－γ衰减．其中，对ＭＬ＝３．０余震有γ≈３；对ＭＳ＝６．７和ＭＬ＝４．０余震有γ≈２；而对ＭＬ＝３．５和另一个ＭＬ＝３．０余震有γ≈２．５．ＭＳ＝６．７余震的拐角频率表明，它的震源尺度较小，意味着该余震是一个面积较小但强度较高的障碍体的破裂．
Broadband seismic records can be expressed as a function of the source time, the convolution of the spreading operator and the scattering / damping operator. In the case where the propagation operator is independent of frequency and the scattering and attenuation effects of the seismic waves can be represented by a Q value that varies with frequency in a manner of Q-1 = Q-11 + (Q2ω) -1, by combining the displacement spectra, The source spectrum can be estimated directly, and the effect of Q on the seismogram is automatically eliminated in the spectrum combination. This algorithm has been used to deal with the near-source broad band seismic records of 1988 aftershocks of the Lancang-Gengma earthquake in Yunnan, China. The results of the ML = 3.0 and ML = 3.5 aftershocks show that the same high frequency attenuation trend can be obtained from the broadband seismic records on different stations. The strong aftershock processing results for MS = 6.7 show that the same source parameters can be obtained from different seismic stations, and the estimated parameter values also agree with those obtained by empirical Green’s function method. The high frequencies of these aftershocks show a typical f-γ attenuation. Among them, γ≈3 for ML = 3.0 aftershocks; γ≈2 for MS = 6.7 and ML = 4.0 aftershocks; and γ for ML = 3.5 and ML = 3.0 aftershocks for γ = ≈2.5. The corner frequency of MS = 6.7 aftershocks indicates that its source scale is small, meaning that the aftershock is a rupture of a smaller but higher strength obstacle body.