PALEOSOL-BASED PALEOCLTMATE RECONSTRUCTTON OF THE PALEOCENE EOCENE THERMAL MAXTMUM, NORTHERN ARGENTINA

CECILIA EUGENIA DEL PAPA; ELIZABETH ANDREWS; TIMOTHY WHITE

Congreso; XX Congreso Geologico Argentino; 2017

The Paleocene-Eocene Thermal Maximum (PETM) is a well-documented, relatively short-lived, warm episode in Earth history. Previous studies completed on marine and continental strata spanning the PETM have focused on understanding the magnitude of warmingand other atmospheric changes. These studies, completed largely in the NorthernHemisphere, report warming that ranged from 4-8ºC above mean annual paleotemperatures prior to war - ming. Tn this study,paleosols in the Salta Basin, northern Argentina,are used toreconstruct paleoprecipitation rates and mean annual paleotemperatures of the Southern Hemisphere from before, during and after the PETM. Carbon isotope data are used to: 1) identifythe horizon in which the PETM and other Eocene hyperthermals are recorded; and, 2) to interpret perturbations of the global carbon cycle during the PETM. At the height of the PETM, paleopre- cipitation proxiesindicate 1500 mm of annual rainfall and a temperature increase of -5ºC from pre-PETMvalues. Carbon isotope data records three negative carbon isotope excursions during the PETM in this region,suggesting the possibility of three distinct,rapid releases of isotopically depleted carbon into the ocean-atmosphere system. The results presented here are one of only a few paleoclimate reconstructions from continental sediments spanning thePETM in the Southern Hemisphere.