FluidMICS

The FluidMICS project is funded by the European Research Council (Consolidator Grant, 2021-2026). Our goal is to further improve and apply fluid inclusion microthermometry in speleothems. The microthermometry approach takes advantage of the temperature dependence of the density of the water that is enclosed in speleothem fluid inclusions. This purely physical basis distinguishes the method from other paleo-thermometers that often rely on empirical calibrations. So far, this method has only been applied to a small number of stalagmites from Northern Borneo. In this project, we apply the method to more samples from different locations and climates. The information we obtain about the magnitude and timing of past land temperature changes will contribute to a better understanding of our climate system under different atmospheric CO2 concentrations, and in times of rapid change, to test climate models used for future projections.

In parallel, we work on further improvements of the method both on the analytical and the theoretical side. The main objectives are to explore and extend the applicability of the method to stalagmites with various calcite fabrics and to small inclusions of less than 500 µm3. Furthermore, we investigate potential non-thermal influences on the fluid inclusion - calcite system that may affect the measured temperatures and contribute to the scatter of the data. To this end, we conduct a series of experiments and apply various imaging techniques to better understand the structural relations between inclusions and surrounding calcite.