Lithology and compositions of the Onnuri oceanic core complex, Central Indian Ridge

This dataset provides a comprehensive suite of petrological and geochemical data used to characterize the subseafloor architecture and lithological variations of the Onnuri oceanic core complex (OCC) at 11°25’S on the Central Indian Ridge. The data is derived from rock samples recovered from the detachment fault surface and its extensively exposed 1-km vertical slopes (the NE and SE slopes) through targeted dredge hauls and Remotely Operated Vehicle (ROV) dives. These datasets offer fundamental geological constraints on the crustal composition, magmatic evolution, and strain partitioning mechanisms beneath a high-temperature ultramafic-hosted hydrothermal system.