Navigation Coordinate Errors

This dialog summarizes results of tests that attempt to identify bad or missing trace coordinates based on unusual distances between adjacent traces. A larger than normal gap may indicated missing coordinates (values changing from "real" coordinates to (0,0) and back again). No gap at all may indicate that all coordinate headers are identical and that perhaps the wrong byte-offset is being used. In either case, functions that calculate the length of the profile or distances between traces may give unacceptable results if these trace coordinates are used.

Large Gaps Between Traces

List contains pairs of adjacent traces with unusual or unexpected distances between them. If there are many pairs listed, you may have the incorrect trace header selected for trace coordinates. If only a few entries are shown, they may help you locate corrupt or missing values in the trace headers.

Start TraceViewer

Open the TraceViewer tool so that you can examine the trace headers directly and attempt to determine the cause of the problem. Use this with the list of trace-pairs to examine the correct traces.

More

Optionally view statistics about the calculated distances between all of the traces in the file.

Notes

Errors in the SEG-Y data file may not be possible to resolve in SEG-Y Reader. However, you may be able to dump selected headers to a Geosoft Database file. Within Oasis montaj, you can identify spikes in the data, correct or interpolate through bad values, and export to an ASCII file suitable for use as a navigation file.