PALEOENVIRONMENT RECONSTRUCTION DURING THE PRE-ONSET EXCURSION PRIOR TO THE PALEOCENE-EOCENE THERMAL MAXIMUM

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 organic carbon, 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 spectrometry (ICP-MS). Our data show an increased chemical weathering rate and elevated nutrient condition in the region, which 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, and paleoredox proxies suggest reduced oxygen concentrations of the shallow marine during the POE.