Seismic modulation model and envelope inversion with smoothed apparent polarity

Abstract

The seismic modulation model analyzes a seismogram from the low and high-frequency information, which is different from the traditional convolution model. In the modulation model, a seismogram is regarded as a modulated signal and its envelope is the amplitude-modulation component containing the low-frequency information. On this foundation, the envelope of seismograms can be used to recover a very smooth background structure. However, amplitude demodulation methods can only obtain the absolute value of the envelope, which cannot reflect the polarity changes of the amplitude information in seismograms. To solve this problem, we consider the low-frequency modulation from both the amplitude and polarity points of view. We extract a modulator signal with smoothed apparent polarity, which contains the amplitude and polarity information in seismograms. The new approach can broaden the modulation model theory for seismic signals. Good results from examples for application to envelope inversion demonstrate the good performance and potential of the proposed method.