After a jackup unit is removed from a site, depressions are left in the seabed where the spudcans were located. The soil in way of the footprints has modified physical profiles of the seabed and soil properties.
Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global Standards
Sea floor depression which remains when a jack-up is removed from a site.
Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global Standards