Original Cross Section Areas
This method simply uses the area of each cross section, with each cross section bounded by its own highest elevation. This method is useful when the channel has migrated laterally and you want to consider the full width of the channel in both the new and old surveys.
Common Cross Section Extents
This method constrains both cross sections to just the stations that are surveyed in both the new and old survey. Cross sections are capped at their highest elevation.
This method uses the full extent of both cross sections, but extends them vertically up to a reference plane. This upper elevation can optionally be lowered with a user-specified offset. Areas above the offset reference plane are excluded.
Inside Reference Stations
This method constrains both surveys laterally to their common extent and within a left and right reference station. Cross sections are capped at their highest elevation.
Outside Reference Stations
This method only considers area of both cross sections that is outside of the reference stations, but common to both cross sections. Cross sections are capped at their highest elevation.