Whole rock major and trace element analyses (dataset 2) of samples recovered during IODP Expedition 398 (Site U1595). Site U1595 (proposed Site CSK-08B) is located in the southern basin of the Santorini caldera at 291 meters below sea level (mbsl). It was drilled in three holes (U1595A-U1595C) to a maximum recovery depth of 127.0 meters below seafloor. Whole rock major and some trace element compositions were determined by ICP-OES, following a lithium borate fusion. High-precision trace element analyses were undertaken using ICP-MS, following a lithium borate fusion. LOI (loss on ignition) was measured gravimetrically. All analyses were carried out by Actlabs, Canada. Data analysis was supported by NERC - UK IODP Phase 4 Moratorium Award, NERC Grant NE/X016374/1, Ralf Gertisser. For sample context, see: https://publications.iodp.org/proceedings/398/398title.html https://doi.org/10.14379/iodp.proc.398.109.2024 Dataset 1 available here https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item190167