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Description
Removing footprints from the 3D data set(s)
Footprints are most commonly observed in the 3D seismic volumes. There are various reason for the footprints in the data set. Footprints can be produced either by acquisition or during the seismic data processing. But majority of the footprints are related to Acquisition rather seismic processing. Presence of footprints on the time slices/depth slices or on the stack section masks the resolution that leads to poor interpretation.
So what causes this acquisition footprints?
There are 3 factors which need to be considered during the acquisition survey design. Offset, Fold and Azimuth. Based on the designing of the survey fold is already preset and we can achieve the desired fold but we don’t have control on the Offset and Azimuth since we have logistical issues in the acquisition especially in the onshore. There might be a canal or a village where we can’t lay our receiver spread which creates a void and we miss the Offset and Azimuth information here. The distribution of Offset and Azimuth can be uniform within the bins or it can be vary from one bin to another. It may be uniform in inline direction but not the same case in cross line direction. This results in footprints visible on the time/depth slices. The linear spatial gird pattern seen on the 3D seismic slices are nothing but footprints. In case of the marine data acquisition it might be due to the cable feathering. The other factor which we mentioned due to the seismic data processing but the chances of generating acquisition footprints by means of processing is very minimal. During the acquisition, if we acquired the data in sparse grid we may create some artifacts during the processing. In another scenario if we have a coarse grid then we have the problem of aliasing created by steeply dipping noise events which eventually results in footprints pattern.
Input data
Input DataItem
Input gather
Parameters
SliceNum
Time Window
Parameters for Time1
Time1
Footprint Taper Inlines
Footprint Taper Crosslines
Preserve wave length along Inlines
Preserve wave length along Crosslines
Parameters for Time2
Time2
Footprint Taper Inlines
Footprint Taper Crosslines
Preserve wave length along Inlines
Preserve wave length along Crosslines
Use Adaptive Substration
Threshold for Adaptive Substration
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