Introduction to noise and multiple attenuation
In worldwide assortment of shot records, we examined noise and signal characteristics of seismic data from 40 common-shot gathers. Noise generally is classified into two categories — random noise and coherent noise. The random noise category includes noise in the temporal direction and spatially random noise that is uncorrelated from trace to trace. The first type of random noise usually is stronger at late times than early times in recorded data. Time-variant bandpass filtering usually is applied to attenuate much of the temporally random noise. A powerful process that attenuates much of the random noise uncorrelated from trace to trace is conventional CMP stacking. By using multiple receivers per channel, nultiple sources per record and multiple fold of coverage, signal-to-noise ratio is increased significantly. A comprehensive review of random noise and its analysis is given by Sengbush . The coherent noise category includes linear noise, and reverberations and multiples. Coherent linear noise types include guided waves, which often are abundantly present in shallow marine data, ground roll and noise associated with shallow water-bottom side scatterers.
- Sengbush (1983), Sengbush, R.L., 1983, Seismic exploration methods: Internat. Human Res. Dev. Corp., Boston.
- Multiple attenuation in the CMP domain
- Frequency-wavenumber filtering
- The slant-stack transform
- The radon transform
- Linear uncorrelated noise attenuation
- Multichannel filtering techniques for noise and multiple attenuation