Porifera-microbialites of the Lower Liassic (Northern Calcareous ...

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4.13. Moosbergalm (M)
Geological Setting:
� The Moosbergalm (ÖK50 / Blatt 95 Sankt Wolfgang, R 07 5710, H 52 7675) is located east of the
toll road that runs through the Osterhorn block and connects Voglau (between Golling and
Rußbach) with Weißenbach (at Wolfgangsee) (Fig. 25, Pl. 6G). Liassic sediments are preserved
due to a small basin that had formed in this area during Hettangian time by the collaps of a part
of the southern Triassic carbonate platform.
� The profile at Moosbergalm starts south of the meadow at the Lienbachsattel that is formed
by Triassic Dachsteinkalk (M 4, 5, 12). It is followed by Liassic limestones that build the
meadow encompassing grey siliceous limestones (Fleckenkalke and Hornsteinknollenkalke) that
alternates two times or more with red Adnet limestones/breccias. Both are very badly exposed
along west-east-running faults, sometimes doubling the profile and otherwise pinching out
laterally.
� According to Plöchinger (1953) the sequence of grey siliceous and red Adnet facies was
folded together, then squashed and partly broken, thus today the meadow sequence most likely
represents only the eroded or torn flancs of several folds.
Facies Analyses:
Fig. 25. Location map of the
Moosbergalm showing the areal
extent of sampled Triassic-
Jurassic sediments.
� “Hornsteinknollenkalke” (M 6+9, Pl. 6H, 7A): Biomicrites with crinoidal debris and high
amount of isolated and mostly dislocated sponge spicules (monaxons and hexactins).
Microbialites are absent. Bioturbation occurs as small burrows. One sampled layer shows