Autofluorescence of fossil pollen and spores with special reference to age determination and coalification

In the present study the primary fluorescence phenomena of fossil pollen and spores are described. This new method in palynology is based on a large number of fluorescence microscopical observations and spectrophotometrical determinations of palynomorphs from deposits of various type and age. It resulted in three principles: the relationship between fluorescence colour to type or form of pollen and spores (Plate I and figs. 21—22), the change in their fluorescence colour from blue or green to red or brown with increasing geological age (Plate II, III and fig. 24) and a similar colour change with increasing rank of coal of the embedding deposits (fig. 33). These phenomena appear to be in accordance with other fossilization and coalification studies of fossil palynomorphs by various authors. For the preparation of pollen samples and the microscopical determination of fluorescence colours some special techniques have been adapted or developed. The discoveries of fluorescence palynology can be applied to various questions, as, for instance, the study of pollen morphology and corrosion susceptibility and the age determination of those deposits, for which conventional pollen analysis fails. Such datings of Cenozoic rocks can be carried out with an accuracy of more than 80 %. As an example a number of age determinations of contaminated sediments is given (Plate V). Besides, fluorescence palynology may be used to determine the rank of coal of palynomorphs in coalified rocks in that part of the coalification series, ranging up to a fixed carbon content of about 70 %. The explanation of the fluorescence phenomena described, meets still great difficulties, due to the inadequate knowledge of the chemical nature of the walls of fossil pollen and spores. Once again it is proved by this study that fossil palynomorphs are less resistant to fossilization and coalification than has been previously assumed.