Methods and Instruments
Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP MS) is used to obtain a concentration time-series of trace elements including phosphorus, aluminium, zinc, copper, and lead. These trace elements are leached from ash and may increase in the stalagmite after a fire event deposits ash on the surface above the cave.
Synchrotron X-ray Fluorescence Microscopy (XFM) is used to map elemental concentrations of calcium (Ca), bromine (Br), and strontium (Sr). Sr maps show clear seasonal changes in Sr concentrations which can be used to develop a chronology. The Sr chronology is cross-checked against thin sections which can show dark organic matter bands in the wet season.
Isotope Ratio Mass Spectrometry (IRMS) is used to understand changes in δ18O and δ13C which can provide information on climate and hydrology through the stalagmite record.