Speleothem organic acid luminescence intensity ratios: a new palaeoenvironmental proxy

One area of recent speleothem research has been the analysis of luminescence variations. Here we present luminescence data for the dominant luminescence centre (excitation wavelength 330 to 390nm; emission wavelength 390 to 460nm). For many speleothems this peak can be resolved into two luminescence maxima. Data presented here, from a variety of speleothems and a wide range of cave locations, suggest that in many cases the ratio of luminescence intensity of these two luminescence intensity sub-centres can provide a more sensitive record of luminescence variations. Also, in some cases, it can provide a palaeoenvironmental proxy.