PALEOENVIRONMENT RECONSTRUCTION DURING THE PRE-ONSET EXCURSION PRIOR TO THE PETM THROUGH THE USE OF GEOCHEMICAL PROXIES

Despite significant progress in our understanding of the Paleocene-Eocene Thermal Maximum (PETM) in the major oceans, a critical research gap remains in the eastern Tethys. The eastern Tethys is an important low latitude source of heat and moisture, and an important site for organic carbon burial, which may have played a significant role in modulating the global carbon budget. Warming conditions may have enhanced the organic carbon burial through increased productivity and development of anoxic conditions. In this study, we reconstruct the productivity and redox conditions in the eastern Tethys at the Kuzigongsu section in the Xinjiang Uygur Autonomous Region in Northwestern China during the pre-onset excursion prior to the PETM. Major and trace elemental data was recovered from the samples through the use of an inductively coupled plasma mass spectrometer (ICP-MS) and Isotopic Ratio Mass Spectrometer (IRMS) for δC values. Our data shows an increased chemical weathering rate and elevated nutrient conditions in the region. This led to higher productivity likely associated with the carbon emissions in the early phase of the North Atlantic Large Igneous Province (NAIP). The amount of CO2 increase during the pre-onset excursion (POE) interval is considered to be small relative to the PETM, however paleoredox proxies still suggest reduced oxygen concentrations of the shallow marine during the POE.