Polarity preserving decon in ``N log N'' time
Prevalence of Ricker wavelet
Two goals of seismogram source waveform estimation conflict. They are:
Preserve and clearly exhibit the polarity of seismic reflections.
Estimate and use for data processing a source waveform that is causal, namely, the response vanishes before the excitation.
When we honor one, we find trouble with the other. This conflict will be defined and resolved here.