Specialist vessels carry out geotechnical surveys of the sea bed.
Who supplies them
Fugro, G-tec, Gardline and Horizon Geosciences.
The vessels are typically 60 to 100 m long and typically operate their drilling systems through a central moon pool. Some sea bed systems are deployed over the side or stern via A-frames or heavy lift cranes. The vessels are able to operate independently in remote locations.
Jack-up vessels can also be used (albeit smaller than those used for foundation and turbine installation) where water depth and sea bed conditions are suitable. The vessels must be able to position themselves at specific locations for borehole sampling using dynamic positioning or anchors and must be able to withstand unfavourable sea and weather conditions.
The vessels provide a stable platform for the acquisition of samples and in-situ testing. Due to the expense of hiring these vessels, multiple crews, including highly specialised equipment operators, are used and the vessels have sleeping berths and living quarters to allow the vessel to have an operational endurance of over a month.
Offshore laboratories also allow for data acquisition and processing onboard. Crew rotations month by month enable a constant flow of data collection, processing, and interpreting.