Diatom abundance from IODP Site 383-U1541

The upper sediment of Site U1541 (42 m) was recovered from the Subantarctic Zone, located in the central-eastern Pacific Southern Ocean, during IODP Expedition 383. The record spans 1.45 Ma, with temporal coverage focused on the Mid-Pleistocene Transition (~1.25–0.7 Ma). The sediments were analyzed for diatom abundances at a spacing of ~10 cm, processed using standard diatom preparation techniques, and analyzed by light microscopy (400–500 valves per sample) with taxonomic identification to species level.