This surveyed area is an extension to the existing Galloper Offshore Wind Farm covering an additional 128km2 creating enough energy each year to power hundreds of thousands of homes.
Robertson Geo Services supplied PS Logger® and 3-Arm Caliper probes, deployed in five boreholes ranging from 60m to 80m depth. Logging the PS Logger® at 0.5m intervals and using generous overlaps between each 5m casing pull, the engineers onboard were able to provide high quality data in difficult ground conditions against the background noise resulting from strong currents in the area.
The Robertson Geo PS Logger® is used to measure compressional and shear wave velocities in both soils and rocks. It operates using indirect excitation rather than mode conversion as in a conventional sonic and can acquire reliable high-resolution P and S wave data in borehole depths of up to 600m. The 3-Arm Caliper probe (with natural gamma) provides a detailed profile of the drilled borehole, highlighting weaker areas evidenced by cavitation or borehole wall rugosity, serving as a QC check for the PS Logger® data.
By providing detailed in-situ velocity profiles, used for calculating formation stiffness, PS Logger® data is an invaluable asset for developing ground models and optimising foundation designs.
