If the data in the preview window is garbled the cause is likely an incorrect number of samples or trace data type. The wizard seldom fails to auto-detect the trace data type for your SEG-Y files, though an error in the binary header or 8-bit data can cause problems. Go to the Binary Header tab and examine values. If the problem is not immediately apparent, try one the following:
Go to the Trace Data tab and look at the area labeled Samples. Is the trace range approximately what you expected? If not, figure out the number of traces and samples per trace you should expect using Trace/Sample Math.
Note the number of samples listed in the Binary Header tab. Go to the Trace Header tab and double-click on the first trace in the lower half of the window. Look for a value in byte 115. Sometimes the number of samples for an individual trace is entered at this location. If you find a value, compare it to the value in the binary header and if it is different, return to the Binary Header tab and type this value into the box.
Look at the Detected Trace Sample Format. Is this the trace data type and endian you expected? Try other trace data types and endians. The wizard may complain that it ‘Can't Read SEGY File’. Dismiss these error messages. Observe the preview and the actual numeric trace samples to find a better match.
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