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Trace header
The SEG-Y trace header contains 240 bytes of binary trace attributes. The Trace header tab allows you to browse through all trace headers in the file. The four 'player' buttons takes you to the first-, previous-, next-, and last trace. You may also enter the trace number directly in the trace number line edit. If you change a setting (e.g. Type) that affects the information in the Trace header tab, you need to enforce an update - click button for next trace, for example - for the information to change.
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The Trace header tab is an invaluable tool for deciding unknown byte positions. If e.g. shot point byte position in your SEG-Y file is unknown to you, try stepping forward trace by trace by using the Next button and look for a number that increases by one for every other trace. {Tip} |
Scan results
After performing a Scan the results are displayed under this tab. If more than one file is selected, the scan results are updated continuously as the different files are scanned.
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- Look for information about the shot point byte position in the EBCIDIC header.
Select the Trace header tab to view the SEG-Y file's headers trace by trace. The byte positions' values are continuously reported as you move through the file. By closely observing how the values change you should be able to determine the correct byte position.
Note Shot points often appear in pairs, i.e. they change every other trace.
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Before importing multiple SEG-Y files, try importing a single files making sure that your settings are correct. Make a note of your settings. |
Import 3D seismic
Make sure you have read about the different elements of the import menu above, before you read this section.
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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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