Preface The expedition ARK XIX/3 with the German icebreaking RV ...

Pitch correction
Due to assembling of the multibeam echosounder on "Victor 6000" and its
position with regard to VRU, a pitch correction is needed.
Before pitch correction
After pitch correction
Tide correction
The final goal of microbathymetry is to produce maps given absolute depths
with regard a unique reference, respecting the accuracy of the soundings
delivered by the multibeam sounders.
All measurements done in real time are relative to sea surface. So, it is
needed to correct the bathymetric data from the tide effect which maximum
amplitude was about 2.5 meters is Håkon Mosby area during the two "Victor
6000" dives.
Navigation correction
A major problem is due to navigation accuracy which involves bad
positionning of geological structures.
A special module (Regina) has been developed specifically to solve this type
of problem, with a methodology as followed:
bathymetry is displayed by contour lines along the ship’s track,
operator visually and manually detects identical geological structures
surveyed on different profiles,
an automatic adjustment of navigation is computed to position the
identical structures at the same location.
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