A reappraisal of the stratigraphy of the upper Miocene unit X in the Maaseik core, eastern Campine area (northern Belgium)

The stratigraphy of the Tortonian-Messinian sequence from the Maaseik core, located on the shoulder of the Roer Valley Graben (RVG) in the eastern Campine area in northern Belgium, was improved. The analysis of the marine palynomorphs (dinoflagellate cysts and acritarchs) from the uppermost part of the Breda Formation, the unnamed unit X and the basal part of the Lower Waubach Member led to the recognition of the mid to upper Tortonian Hystrichosphaeropsis obscura biozone. Therefore deposition of this entire analyzed sequence took place sometime between 8.8 to 7.6 Ma. Paleoenvironmental interpretation of the palynomorphs points to shallow marine conditions and most probably a stressed environment during the deposition of unit X. A comparison with the time equivalent stratigraphy in the nearby Belgian Campine, the Dutch RVG and the German Lower Rhine Basin allowed the identification of the Inden Formation and required a shift in the base of the Kieseloolite Formation compared to the earlier lithostratigraphic interpretation of the Maaseik core. The regional stratigraphic scheme shows the progressive northwestward extension of the river facies from the Lower Rhine during the late Tortonian.

Nomenclatural novelties in the fossil genus Spinopalmoxylon (Arecaceae) from the Central European Oligocene and Miocene: A whole-plant concept for Spinopalmoxylon daemonorops

The fossil genus Spinopalmoxylon from the Central European Oligocene and Miocene comprises three species: S. daemonorops, S. parvifructum sp. nov. and S. cicatricosum sp. nov. Here the species S. daemonorops is amended and its name is proposed as nomen conservandum against S. teutonicum. A series of synonyms is provided. In addition, two new species are described from late Oligocene deposits of Niederpleis: S. parvifructum sp. nov. (pistillate inflorescence, fruits, and seeds) and S. cicatricosum sp. nov. (staminate inflorescence and pollen). These three Spinopalmoxylon species together are proposed as a whole plant. Floras with the Spinopalmoxylon palm reflect the vegetation of the near-shore fluvial floodplain and back-swamp environments of the late Oligocene (Chattian) Köln Formation (Clay 1) and early Miocene (Burdigalian) Ville Formation (Seam 6A) in the northern foreland of the Siebengebirge Volcanic Field near Bonn, at the southeastern margin of the Lower Rhine Basin.