Directional illumination technique of electromagnetic vibrator system

To improve the quality of seismic data in controlled source seismic prospecting, we developed Directional Illumination Technique (DIT). It states the principle of DIT, describes the method of directional illumination processing, studies the characteristic of seismic wave field corresponding to DIT. Here we designed horizontal and dip layer media models, simulated seismic data from electromagnetic vibrator system, and synthesized one-shot seismic record with DIT. To estimate time delay of reflectors underground, cross-correlation detection method is used. To analyze the performance of DIT, we calculated SNR (signal-to-noise ratio) of reflected wave signal before and after directional illumination processing for both media models. The result shows that SNR of regular seismic data is -26.09dB, however, SNR increased to -20.72dB with DIT averagely for horizontal model. SNR increased 3.01dB for dip model. It concludes that cross-correlation method works well to detect time delay of reflected signals, DIT could boost SNR of reflected waves for layer medium.