Dataset: Rock and sediment samples collected by ROV SuBastian during the Octopus Odyssey expeditions Fkt230602 and Fkt231202 aboard R/V Falkor (too) in Costa Rica (2023)

Sampling was conducted across six main geological features in the Pampa Submarina region off the Pacific coast of Costa Rica, including several hills, knolls, a seamount, and the surrounding abyssal plain.

Push core sediment samples were collected in the abyssal plain where sufficient sediment thickness allowed coring. Rock samples were collected during ROV SuBastian dives when suitable outcrops were encountered. Both push core and rock samples were collected using the ROV’s manipulator arms.

Rock samples were labelled using the standard code used in the expedition (Cruise ID, followed by a sequential sample code used for each expedition, and then the type of sample (S for sediments, R for rocks); e.g. FKt230602-006-S). Samples were photographed on board following the standards methods used for rocks.

Samples from these collections were allocated to various biological, physical, geochemical, and ecotoxicological analyses. These included characterization of sediment, fungi, worms, protists, and meiofauna, physical sediment descriptions using smear slides, geochemistry, ‘omics-based taxonomic and functional assessment of microbiomes, Cd exposure ecotoxicological experiments and background metal concentration of the 0-10 cm layer, namely by quantifying Cu, Fe, Mn, Zn, Ni, Cr, Pb, Cd.