FLORISTIC CHANGES AT THE PETM IN THE NEOTROPICS

The consequences of the Paleocene-Eocene Thermal Maximum on tropical vegetation are unknown. Previous studies have shown that this interval is associated with a sterile zone that does not yield pollen and preserves very few organic matter. This pollen recovery gap is widespread throughout the Neotropics (mainly Colombia and Venezuela). Here, we report three new sections in eastern Colombia that have yielded palynofloras from this interval. Strata facies indicates a floodplain environment. The record suggests a floristic turnover, with many new species arising rapidly in the Eocene. The change is not associated to any lithofacies change. Uppermost Paleocene palynofloras have a low alpha diversity and are widespread across the region, while lowermost Eocene palynofloras have a higher alpha diversity and are more restricted geographically with a higher degree of change across the landscape.