Merge Log Curves Transform

This transformation splices together several log curves into a single log.  This can be particularly useful for combining several different log runs into a single curve in Petra.  This log transformation is available on the Advanced Transforms tool.

Source Curves to Merge – This option selects the curves to splice together.  

Target Curve (Merge Into) – This option selects the destination curve.  

This tool obeys a couple of rules when two or more logs have overlapping non-NULL values.  Petra always preserves the target curve’s values, and won’t write overwrite values from any of the source curves.  In the example above, Petra won’t overwrite any values already in the “Combined” target curve.  Additionally, when two or more source curves overlap, Petra will use the first source curve listed.  In the example above, Petra will use RUN1’s values over RUN2, and RUN2’s values over RUN3.

To reorder the Source Curves to Merge list, go to the Logs tab on the Main Module.  Here, select the Maintenance button to open the Log Maintenance window.  Select “Set Display Filter.”  Here, reorder the log curve names as desired.

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