Vibroseis Data Harmonic Interference Suppression By Shaping Filtering

Petroleum has become one of the most important energy-drivers in human society today, Oil-gas exploration is the first key to it. Owing to the social significance and technical significance like security, environmental friendliness and maneuverability, vibroseis has become one of the main sources for seismic exploration. In the meanwhile, slip-sweeping becomes one of the most important acquisition methods in high efficiency seismic exploration. Because of its particular acquisition way, slip-sweep seismic acquisition has its harmonics collected together with seismic data. To improve the quality of the data we got, suppress the harmonic noise, we need complementary data processing technologies.So far, although there still exists different kinds of advantages and disadvantages, various types of harmonic noise suppression technologies have been developed.In this paper, properties of vibroseis harmonics are first detailed, and then vibroseis seismic exploration and slip-sweep method are briefly explained, for the introduction of the mechanism behind the harmonics noise, the main existing harmonic noise suppression technologies are also commented. Finally, a new slip-sweep seismic data harmonic noise suppression method-harmonic noise suppression by shaping filtering is proposed and tested.This new method assumes that the signal actually send into underground is known. So we can use this signal to design a filter to remove the possible existing harmonic noises so as to leave only the fundamental signal.This method has no requirements on the way of sweeping frequency variation——either ascending or descending, and on the raw data—correlated or uncorrelated. Also it can also attenuate integer-order harmonics and fractional-order harmonics at the same time. In practice, force signal can be used as the signal actually emitted into underground.Theoretical and field data tests show that this method is valid and effective.