The project represented an important milestone for RGS, Next Geo Solutions and the industry in general, as the Sylur now provides much needed additional geotechnical drilling capacity to the expanding requirements of the offshore wind farm industry.
The Nordlicht project site is located north of the island of Borkum and should go online by the end of 2027, with a generation capacity of 980 MW (Nordlicht 1), enough electricity to meet the annual requirement of more than one million average German households. The Netherlands port of Eemshaven served as the vessel’s base of operations for the project.
The initial challenge for the engineer was to assist with the installation of the 2,000m Marine Winch and sheave wheel arrangement onto the rooster box, to exacting safety standards, including weight testing. Once the equipment was installed and fully tested, the vessel proceeded to the Nordlicht site where PS Logging was conducted at seven locations. On each borehole the logging was split into three runs to maximise data recovery should unstable zones be encountered.
The PS Logger® probe, with its integral source, measures compressional (P) and shear (S) wave velocities in a single borehole in soft and hard formations. The velocity data is used to derive Poisson’s Ratio and when combined with density values can be used to calculate the small strain moduli, with Shear Modulus (G) being important for offshore wind turbine foundation design.
The logging programme was successfully completed without any significant problems or deviations from the original logging plan.
