Ground roll attenuation using shaping filters and band limited sweep signals

Abstract

Onshore seismic data often have low signal to noise ratio due to, among other factors, the presence of ground-roll, a noise characterized by coherent, linear and dispersive events with high amplitudes, low frequencies and velocities. This noise overlaps with reflections, hindering the data processing and interpretation. When the attempts to reduce the ground-roll during data acquisition (using source and receiver arrays) fail, several methods can be used in seismic processing. Here we discuss a filtering method based on Wiener shaping filter, its implementation and its main parameters. We also present a different approach based on the direct deconvolution algorithm. The results of the application of direct methods to a real seismic data set are quite satisfactory when compared with those obtained with conventional FK and low-cut filters. © 2012 Sociedade Brasileira de Geofísica.