Menu entry Phase Diff

Computes epicentral distance using travel time differences between pairs of phases. SHM needs to know which phase pairs should be processed if available.

This phase pair list must be specified in the Configure option. Changing the list given here means to retype the complete list including or excluding your changes. Please check for typos and do not use blanks in the list, just separate the phases within the pair with hyphens and the pairs with commas. Phase pairs not listed here are not processed for distance determination. Selecting Phase Diff makes SHM scan all traces for such phase pairs.

Each phase pair is assigned a distance by fitting the travel time difference using the travel time tables in $SH_INPUTS. All distances found are averaged and the mean distance is written to the analysis parameter box.

Known bug: a phase pair has to be selected on the same trace, a P on Z and an S on E are not recognized as a pair. Workaround: select S temporarily also on Z and delete it after the depth determination.

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