The data refer to the geochemical and isotopic characterization of microbial carbonate in the shallow platform of the South Atlantic Ocean, Espírito Santo - Brazil. Geochemical and isotopic analyses were conducted at the LAMIR Institute of the Universidade Federal do Paraná (LAMIR Institute-UFPR). Major element concentrations were determined in three pulverized samples using X-ray fluorescence (XRF) spectrometry on a Panalytical Axios Max instrument with a 4 kV Rhodium tube. Samples were fused with lithium tetraborate/lithium metaborate and analyzed as fused beads. Results were reported as oxide weight percentages (e.g., SiO₂, CaO, MgO).

The study was carried out between 2021 and 2023 on the beach of Castelhanos in a carbonate bank to analyze the depositional dynamics throughout the Holocene. The occurrence of microbial carbonates in the open marine environment is uncommon globally, configuring an excellent proxy for the reconstitution of relative variations in sea level and paleoclimate.