Major and trace element geochemistry of volcanic glass shards from Black Sea marine tephra layers

This repository contains two Microsoft Excel files comprising the complete major- and trace-element geochemical dataset of volcanic glass shards from tephra and cryptotephra layers identified in marine sediment core M72/5-25-GC1 (southwestern Black Sea).File 1 – Electron Microprobe (EPMA):This table reports major element glass compositions (wt.%) obtained by electron probe microanalysis. The dataset includes analyses of individual glass shards, reference materials and secondary standards. For each analysis, oxide concentrations (SiO₂, TiO₂, Al₂O₃, FeO, MnO, MgO, CaO, Na₂O, K₂O, P₂O₅) are provided both as measured values with original analytical totals and as values normalized to 100 wt.%. Sample identifiers and analytical comments (e.g. glass vs. standard) are included to allow full traceability and quality assessment.File 2 – Laser Ablation ICP-MS (LA-ICP-MS):This table reports trace element concentrations (ppm) of volcanic glass shards determined by sector-field LA-ICP-MS. The dataset includes a wide suite of trace elements (e.g. Li to U), together with associated analytical uncertainty expressed as two standard errors (2SE) and limits of detection (LOD) for each element. Analyses of reference glasses and secondary standards are included alongside unknown samples to document analytical performance and data reliability.Both tables are structured to allow direct reuse for geochemical fingerprinting, tephra correlation, and comparative or data-driven analyses. Full stratigraphic, analytical and methodological context for these data is provided in the associated Data Descriptor published in Scientific Data.Citation recommendation:Users of these data are requested to cite both this dataset and the associated Scientific Data Data Descriptor when using the data in scientific publications or derivative works.