Polen y dinoflagelados del límite Tortoniense/Messiniense del sondeo de testigo continuo "Huelva" (cuenca del Guadalquivir, España). Interpretación paleoambiental

Résumé

The palynological study of 23 samples from a l0m section (between 154m to 165 m deep) from the Huelva borehole (Upper Tortonian and Lower Messinian) is presented. This borehole attain 197,5 m deep and was drilled at the western edge of the Guadalquivir basin, near of the bullfight ring of Huelva. It crossed the whole of the «Arcillas de Gibraleón» and the upper meters of the «Calcarenita de Niebla» Formations. The Event 3 of Sierro et al. (1993), based on the replacement of Globorotalia menardii by G. miotumida, have been recognised at a depth of 164m; it is correlated with the Tortonian-Messinian boundary. The palynological content of the samples is well preserved and rich. Dinoflagellate cysts, pollen, spores, foraminifera linings, acritarchs and other palynomorphs including invertebrates, marine and freshwater algae, fungal spores and plant debris are well represented. It allowed the establishment of three palynological zones related with palaeoecological changes both in marine and continental environments.