The upper triassic and jurassic sedimentary rocks of the Sarsteinalm: evidence for the tectonic configuration of the Dachstein block (Salzkammergut region, Northern Calcareous Alps, Austria)

The Jurassic sedimentary rocks in the Sarsteinalm area are so far poorly known with respect to facies and stratigraphy; also their attribution to certain formations is ambiguous. Rhaetian lagoonal Dachstein limestone is overlain by red nodular limestones of the ?Adnet and the Klaus formations (Liassic to ?Bathonian). These are followed by I m thick red radiolarites (Callovian to Oxfordian), thin black radiolarites (Callovian to Oxfordian), mass-flow deposits with components of Late Jurassic shallow water carbonates and finally, only preserved as small remnants, platform carbonates of the Plassen Formation. The latter can be assigned to slope, platform margin and occasionally also closed lagoonal facies of presumably Kimmeridgian age. The sedimentary succession shows that no mass-flow deposits with components of Hallstatt limestones occur in the study area. It can thus be excluded that slide masses of Hallstatt limestones were transported over this area during Callovian to Oxfordian times. Therefore, the Sarsteinalm area can be considered an isolated block from the Dachstein Block by an east-west striking fault.