Zur Bilanz des Buntsandsteinbeckens (Korngrößenverteilung und Gesteinsbruchstücke)

The Lower Triassic Buntsandstein red beds in Germany were deposited in a river system discharging into a northern basin of varying salinity. In this basin, the main direction of material transport was probably towards the Southeast (Poland), where occasional outlets were open. The median grain size of the fluvial sandstones decreases towards the North (fig. 6): Near the delta, they are finer than the sandstones in the northern basin. This observation together with the differences in feldspar and rock fragments composition indicate that the river system did not contribute to the basin sandstones. Characteristic rock fragments made it possible to estimate the influence of an eastern tributary. The sand size rock fragments can only in part be traced back into conglomerates that occur near the Bohemian Forest, in the Black Forest, and in the Vosges. Most of the debris of the fluvial sandstones derived from the southern rim of the Paris basin, though according to a material balance, a major contribution came from the “Vindelician Ridge” (S. Germany). Abrasion of the rock fragments due to transport is shown by their grain size distribution.