Carbonate coulometry data of sediment cores collected from the Semenov Hydrothermal Field region of the Mid-Atlantic Ridge during the RRS James Cook cruise JC224 (March - April 2022)

Sub-samples from sediment cores collected from the Semenov Hydrothermal Field region of the Mid-Atlantic Ridge during the RRS James Cook cruise JC224 (March - April 2022) were taken for geochronological analysis. Bulk sediments were prepared for calcium carbonate measurements which are required prior to further carbonate isotope analysis. This dataset includes calcium carbonate measurements of the JC224 sediment cores measured using coulometry at the SEAPORT Laboratories, University of Southampton. The data were collected as part of a PhD project funded under NERC's Ultramafic-hosted mineral Resource Assessment (ULTRA) project, grant reference NE/S004068/1, and the sediment cores are currently stored at the BOSCORF for long-term preservation.