A Stratigraphic Record of Tropical Cyclone Events in Low-Lying Yucatan Peninsula

Paleotempestology, the study of ancient storm events, is a field that is currently growing thanks to new techniques for identifying large storm events in climate archives. New identification methods of pre-historic storm events are beginning to impact our understanding of how tropical cyclones fit into the climate system. This research aims to create an inexpensive, first order storm identification method for stalagmites in low- lying karst regions based on clastic deposits layered within the calcite of stalagmites. Many caves in the Yucatan Peninsula are partially submerged when the water table is at its normal height. These caves flood when a large storm moves over the area when the regional water table rises a few meters for days at a time, depositing a layer of mud and debris on cave surfaces. As the water table subsides, the drip water pushes the mud from the top of the stalagmite and speleothem calcite continues to be deposited and the record of the storm is preserved as a dark mud layer. Stalagmite CH-1 was collected from the cave Chaltun-Ha outside Rancho Chaltun-Ha in the Mexican state of Yucatan. A cross section reveals sedimentary mud deposits present within the calcite layers. We will relate the mud layers to local modern storm history by layer counting and radiometric 210Pb, 137Cs, and/or U/Th dating techniques. We also tested the tropical cyclone origin of the post mud-layer calcite using an established stable isotope technique that looks for excursions in δ18O values.