EVIDENCE OF LATE PALEOCENE-EARLY EOCENE POSSIBLE OCEAN ACIDIFICATION RECORDED IN THE ADRIATIC CARBONATE PLATFORM

The Paleocene-Eocene Thermal Maximum (PETM), a period of abrupt global warming events, is linked to a rapid release of large amounts of carbon into the Earth system. This sudden influx is hypothesized to have caused a mass acidification of surface ocean waters and a decrease in carbonate deposition in shallow water ramps and carbonate platforms. While rapid ocean acidification has the potential to devastate marine ecosystems, evidence of abrupt changes in pH and saturation have only been reported from deep-sea records. A well-preserved shallow carbonate platform from the Kras region of Slovenia records, continuous exposures of long term deposition, including the Paleocene-Eocene boundary, which manifests as a dissolution horizon. Through the analysis of dissolution surfaces found in this region, shallow platform ocean acidification is considered as a possible cause for the horizons. We analyze boundary samples to determine if the surfaces formed in an acidified ocean, subaerially, or are due to erosion diagenesis (i.e. stylolitic) using petrography and elemental mapping of the boundary. These surfaces have been analyzed using the Environmental Scanning Electron Microscope (ESEM) Energy Dispersive Spectra (EDS) to create a preliminary elemental map of the focus area. Then, samples will be mapped on the Electron Microprobe (EPMA) to gather more detailed data on the boundary composition to further explain the preserved surface of the PETM. The analyses of these dissolution surfaces in the Kras region will be used to determine whether ocean acidification occurred in this region during the PETM.