Application of Coherent Noise Attenuation to 4-C Ocean Bottom Cable Seismic Data from the Niger Delta

Seismic surveys are typically performed in uncontrolled environments. Moving vehicles, animals or humans, including faulty recording instruments, pipelines and oil production well pumps can degrade the quality of the recorded seismic data with broadband coherent noise. The efficient attenuation of coherent noise in seismic data is therefore of high importance for high quality seismic images. Coherent noise suppression is particularly challenging in an ocean bottom cable seismic data since the level of noise recorded by the hydrophone and geophone sensors vary considerably. This becomes even more challenging when the hydrophone and vertical geophone data are to be summed for enhanced multiple attenuation without introduction of artefacts in the data. In this work, we present a procedure that effectively suppressed coherent noise in a 4-C seismic data from the Niger Delta, based on the application of a spatial filter in the frequency-offset domain, with additional shear leakage noise removal on the vertical geophone data