The animation shows a simple processing sequence of a seismic line using the industrial software SPW3

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  Step 1: Amplitude recovery and deconvolution.
  Spectral whitening is currently done for deconvolution. The Spectral Whitening step is a multi-banded spectral whitening method for balancing the energy of the selected frequency bands of the data. The start frequency is 50 Hz. The end frequency is 250 Hz. Figure is the comparison of shots before (on the left) and after ( on the right) spectral whitening. Due to the high value (50 Hz) of the start frequency, the pseudo Rayleigh modes have been filtered. However, the shot is highly corrupted by the air wave.


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  Step 2: Velocity model.
  Moveout corrections compensate for the obliquity effect of the raypath, due to the offset variation between source and receiver. Reflection arrival times are restored to the times for zero offset traces.
  These corrections are called Normal Move Out (NMO) corrections. A velocity model is needed. It is a stacking velocity obtained by velocity analysis. Figure shows the velocity model used. The curve in red is the interval velocity model. The curve in blue is the velocity model used for the NMO correction.


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  Step 3: CMP stack.
  The NMO correction introduces a distortion or stretch of the seismic traces. The stretch depends on the time, offset and velocity model. It is much more important for the large offsets, the short arrival times and the low velocities. A stretch mute is used to suppress the stretch effect. In order to reduce the noise introduced by the air wave, a tail mute is applied to each shot after amplitude recovery. Figure on the left shows a shot after amplitude compensation, deconvolution, NMO correction, stretch and tail mutes.
  Figure on the right shows the CMP stacked section. The section has a V shape. The V shape is due to the application of the tail mute. On the seismic section, we can clearly see seismic horizons in the 25 – 150 ms time interval.


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  Step 4: Residual static corrections.
  In order to compensate the effect on the weathering zone, surface consistent source and receiver statics are computed. The Automatic Residual Statics step uses a least-squares linear inversion routine to decompose traveltime equations into source, receiver, CMP, and offset related terms. The pick times input to the inversion are picked automatically using cross correlation in a specified time window. The correlation window starts at 30 ms and ends at 150 ms. The maximum allowable static is 6 ms. Figure shows the computed surface consistent residual statics.


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  Step 5: CMP stack without and with residual static corrections.
  Figure shows the comparison of seismic sections without and with residual statics. The residual statics improve the quality of the CMP stack.