Infrared video microscopy—an efficient-method for the routine investigation of opaque organic-walled microfossils

Dark or even opaque organic-walled microfossils are frequently represented in palynological residues which are derived from sediments of high maturity. Such particles may be studied surficially by SEM or incident light, but internal details remain obscured. It has been known for some time that transparency may be achieved by applying infrared microscopy, but the method never became routine. We have now assembled an IR equipment which is based on a regular transmitted light microscope and tested our setup on various kinds of palyno-morphse.g. spores, acritarchs, chitinozoans, scolecodonts as well as phytoclasts and zooclasts. Our examples are from several localities of different stratigraphic and palaeogeographic position within the Palaeozoic. The studies revealed a high potential for IR video microscopy to become an important tool in the study of thermally altered organic particles in palynological slides.