Quelques aspects particuliers de la palynologie du Crétacé Supérieur du Sénegal

Abstract

Palynological investigations of shales and sands of the Upper Cretaceous of some wells in Senegal show, among the usual material of quite well preserved spores, angiospermous and gymnospermous pollen grains, dinoflagellates and hystrichospherids, many fine structures such as various cuticles, sporangia (some of which related to the genus Azolla), and some intact organisms attributed to the algal genus Phycopeltis, from which several steps of its sequence of development were observed. All these elements, combined with qualitative and quantitative studies of ordinary microfossils, provide stratigraphical and mainly palaeoecological information. This is very valuable in order to understand what was taking place on the continental and sedimentary areas. Comparison with the results of other techniques reveal interesting coincidences. Some hypotheses are proposed to explain these facts.