Reconstructing fire history from 1700 to present through the analysis of organic compounds in speleothems: a high resolution study from north-western Australia

Abstract

Organic molecules are excellent indicators of past fires. This research work analyzes the polycyclic aromatic compounds present in stalagmite to assess whether they are related to combustion processes and therefore suitable for the reconstruction of paleo fires in northwest Australia. The further analysis of n-alkanes provides information on the type of vegetation present above the cave as these molecules are proxies of vegetation cover. The work requires the preparation of samples by drilling, acid digestion, liquid-liquid extraction and concentration in organic clean room. This is followed by gas chromatographic analysis combined with single and triple quadrupole mass spectrometry. The expected results will enable to evaluate past fires in terms of intensity, frequency and type of vegetation affected.