Rhenium-osmium abundance and isotope data obtained for the Kyoei-Sakin-zawa Creek Section, Japan. Sample collection August 2021 principally funded by NSF-NERC award. The approximately 340 m stratigraphically thick Cretaceous section mainly comprises organic bearing siltstone, sandstone and interbedded tuff horizons associated with the OAE1d (Oceanic Anoxic Event 1d) interval.