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The Analyze dialog always report the first and last trace. If only two lines appear in the dialog with nothing reported in the Anomaly column, the analysis is done.
SEG-Y analysis panel
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Loading 3D seismic can be a time consuming job, and it is very important that the import settings are correct before starting (to avoid having to do the job again). Therefore, 3D import is usually performed by first setting the import settings, and then performing a scan on the very first inlines only. This is achieved by leaving the Min/Value Inline setting at From file, but setting the Max setting to 10 lines higher than the first inline. This means you have to know the start value of the Inline. You should be able to find this in the Trace header or the EBCIDIC header.
Inline and Crossline byte position
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