Osagia Oncoid

PMH-1, Javorniški Rovt, the western Southern Karavanks.

Trogkofel Formation (upper part)/Goggau Limestone?

Back-reef or back-bank lagoon with well-lit, well-agitated shallow water indicated by dasyclads and Osagid grains.

Bioclastic oncoidal-algal-ehinoderm grainstone/rudstone containing osagid grain with gastropod shell in the nucleus. Note the bioclastic-peloidal infill and biogenic encrustrations (1) coating both infiltrated grains and interior of the whorl-walls.

Dissolution voids filled with calcisiltite extend to the isopachous prismatic rim cement (2nd arrow) while in some places to the biogenic grain (?phylloid alga), which was locally competely leached (3rd arrow).