Global dataset for combined mineral major and trace element data for rocks from the lower oceanic crust

This work presents a Global dataset for combined mineral major and trace element data for rocks from the lower oceanic crust sampled along mid-ocean ridges worldwide. The dataset compiles mineralogical and geochemical data obtained from samples recovered along mid-ocean ridges characterized by a wide range of spreading rates, from fast-spreading to ultra-slow spreading ridges. It integrates published data from the scientific literature concerning the main mafic minerals of the lower oceanic crust, particularly olivine, plagioclase, and clinopyroxene, together with geological and geographical information related to the analysed samples.
For each sample, the dataset includes details such as sampling location, oceanographic cruise, bibliographic reference, geographic coordinates, spreading rate, and sample lithology. The different worksheets contain average major element compositions and, where available, trace element data measured on crystal cores and rims. The dataset includes concentrations of major oxides, petrological parameters such as Fo# and Mg#, as well as trace element and rare earth element concentrations.
The dataset was developed as a supporting tool for petrological, geochemical, and geodynamic studies aimed at improving the understanding of magmatic processes and the evolution of the lower oceanic crust along oceanic spreading centres.

Samples included in this compilation were obtained from previously published studies investigating gabbroic rocks from oceanic ridge environments. The dataset integrates analyses from multiple oceanographic expeditions, drilling programs, and field investigations of exposed oceanic lithosphere. Sampling methods therefore vary among studies and may include dredging, drilling, submersible or ROV sampling. The place of sampling of the lower oceanic crust at each oceanic ridge is reported here.
Major element compositions were obtained primarily by electron probe microanalyses (EPMA), whereas trace element concentrations were mainly determined by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The dataset reports the analytical values as published in the original sources. Detailed descriptions of the analytical methods and protocols are available in the corresponding publications, whose DOIs are provided in the dataset.

No additional processing or modification was applied to the compiled geochemical dataset after data compilation. The dataset preserves the original analytical values as reported in the source publications, ensuring full traceability and consistency with the published datasets.