Bibby HydroMap were commissioned to carry out multibeam and side scan sonar surveys of the seabed at the Conwy Development Field located in the East Irish Sea.
The main objectives of the surveys were as follows:
- A clearance survey for locating a jack-up work barge and drilling rig adjacent to the Conwy platform location.
- A bathymetric and debris survey in the jack-up rig approach and final location.
- A seabed level and debris survey at Conwy platform location immediately prior to its installation.
- A pipeline route survey in the approaches to Conwy is required to establish movement (if any) of sand waves.
Survey lines were created in a SE/NW direction running parallel with the edge of the main rig site survey area. These were spaced at 50m and were extended to the south to cover the sand wave survey area. Two cross lines running at 90º to the main lines were also surveyed.
Multibeam bathymetry and side scan sonar imagery were acquired on each line. The multibeam swath width was typically 100m and the side scan channels were set to record to a range of 75m either side of the line. This ensured 200% coverage of the seabed.
Data acquisition was undertaken from Bibby HydroMap's own dedicated shallow draft vessel Bibby Tethra, equipped with a Reson 7125 multibeam echo sounder, Klein 3000H side scan sonar, C-Nav RTG positioning and IXBlue Hydrins/Octans motion and heading sensors. Each interfaced along with ancillary equipment into a high specification navigation PC running QPS QINSy survey software.
Related Pages: Bibby Tethra
Spec Sheet: Bibby Tethra