Geo-challenges for ground model development in previously glaciated and periglaciated terrains

To achieve a net-zero clean energy future, developing offshore windfarm sites is fundamental to the UK's success in the renewable forms of energy. Integral to this is understanding the shallow subsurface geology which forms the foundation zone to these windfarm developments; particularly the impacts of past glaciations on the sedimentary and structural architecture of the deposits left behind following deglaciation. The range of depositional environments and distribution of deposits including diamictons, organic soils, rhythmically laminated soils, sands and gravels, result in extreme lateral and vertical heterogeneity. This variability, coupled with glaciotectonism, can make wind-turbine installation, kilometres apart, extremely challenging. Therefore, a multidisciplinary approach integrating geotechnical, geological, and geophysical data has enabled geological models to reimagine these ancient landscapes, identifying how they changed spatially and temporally, predict soil-type and behaviour, and furthers the understanding of implications for the foundation design of offshore infrastructure. Here we use knowledge of past glaciations to highlight several instances of extreme vertical and/or horizontal anisotropy, using onshore sites as analogues for observations from the North Sea, illustrating the necessity of fully characterising ancient landscapes to enable the development of ground models which overcome geo-challenges faced by offshore developments.