The Apparent Low Frequency Required by Heterodyning

In this paper, we analyze the effect of loss of low frequency on seismic data and the illusions caused by low-frequency end missing of spectrum .The loss of low-frequency data decreases the main lobe amplitude, and increases the side lobe amplitude which makes the seismic section seem that there exist many false reflected events in fact they are not true interface reflected wave. A method is proposed to extend the low frequencies of seismic data by improved heterodyning (DH+PC) to eliminate this illusion and acquire the improvement of apparent resolution. Proposed DH+PC method overcomes the problem of phase variation and the low frequencies of seismic data could be quantitatively extended, which can decrease the possibility of the mistake in the interpretation of events and avoid regarding the pseudo-event as a true reflection, and provide heterodyned results with better lateral continuity, true events and obvious wave impedance characteristic. Synthetic and real vibroseis seismic datasets are used to validate the feasibility of the proposed method.