Southeastern Section - 74th Annual Meeting - 2025

Paper No. 36-2
Presentation Time: 10:45 AM

A NEW APPROACH TO EXPERIMENTAL CHARCOAL ANALYSES: LESSONS FOR THE CRETACEOUS AND OTHER TIME PERIODS


GALINGER, Matthew1, VACHULA, Richard2, GOERTZEN, Leslie3, HANSEN, Curtis3 and CULLEN, Thomas4, (1)Geosciences, Auburn University, 282 Quad Dr, Auburn, AL 36849, (2)Department of Geosciences, Auburn University, Auburn, AL 36849, (3)Biological Sciences, Auburn University, 282 Quad Dr, Auburn, AL 36849, (4)Ottawa-Carleton Geoscience Centre, Department of Earth Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada

Earth’s climate has historically oscillated between climate states, with greenhouse climate periods offering valuable analogs for future climate projections. The Cretaceous period, characterized by high atmospheric CO2 levels and the absence of polar ice caps, provides insights into potential ecological responses to anthropogenic climate change. This study presents experimental data to inform the use of sedimentary charcoal as a paleofire and paleoecological proxy during the Cretaceous, supplementing the limitations of traditional palynological and fossil perspectives. Our experimental analysis includes 23 broadly sampled plant taxa, focusing on charcoal morphological classifications and a novel set of the following morphometric parameters: aspect ratio (L:W), rectangularity, circularity, and feret diameter. Our results reveal significant differences in charcoal morphometrics at the tissue (e.g., leaf, petiole) and component (e.g., vein, blade) levels, challenging the assumption that larger plant tissues produce relatively uniform charcoal particles. This emphasizes the need for refined morphometric techniques that consider plant tissues as an assemblage of their respective components. Our findings provide a nuanced framework that will improve the accuracy of future charcoal-based paleofire and paleoecology studies, particularly in pre-Holocene contexts, aiding predictions of future ecological dynamics under changing climate conditions.