This dataset comprises quantitative bivalve faunal assemblage data from three vibrocores (Core 1, Core 3, and Core 8) collected during the SEEP (Building a SEabed Environmental baseline for Platform abandonment) campaign in the North Sea in June 2022. The cores were recovered from water depths 40.9, 41 and 43.5 m. Bivalve assemblages were analysed at discrete depth intervals. The different species in each sample depth were noted as present or absent, and species diversity was recorded. All data are depth-resolved and provide quantitative information on vertical variations in faunal composition within the sediment cores. Sample processing and faunal analyses were conducted using standard micropalaeontological and palaeoecological methods, including sediment subsampling, sieving, taxonomic identification under microscopy, and quantitative counting procedures.