PERCOLATION INTO DRAGON’S TOOTH CAVE

Investigations of epikarst hydrological characteristics are important for understanding the complex relationships between cave calcite chemistry and changes in net rainfall, cave drip rates, and fluctuations in cave dripwater. We instrumented Dragon’s Tooth Cave (Marianna, Florida, USA) with an array of instruments to characterize individual rainfall events above the cave and measure hourly in situ drip rates at selected stalactites within the cave. Drip rates at most of the instrumented stalactites increased in response to heavy summer-season precipitation. A sharp increase in drip rates was also observed after several fall/winter months of low to negative net rainfall (i.e., when evaporation> precipitation). This phenomenon may indicate that the stalactites are being fed by a series of connecting reservoirs feeding cracks of various geometries and flow rates. Geological surveys, tracer experiments, and additional time-series data collection will be conducted to further investigate reservoir existence and behaviour. The findings have important implications for the interpretation of speleothem paleoclimate records in terms of both geochemistry and seasonal growth rates. 1