Dachstein limestone and Grey Limestone
210 million years ago, at the end of the Triassic period, a sudden lowering of the sea-bed transformed the entire area from a tidal plain (Main Dolomite) into a tropical shoal constantly covered by water and similar to the present submerged platform of the Bahamas. The climate also changed, from dry tropical, affected by the vicinity of the dry land, to a damp tropical, typically marine climate. The innermost parts of the platform were distinguished by calm waters where carbonate muds deposited. Conditions in the outermost parts of the platform, nearer to the open sea and subject to the direct action of the waves, favoured the formation of sandy underwater dunes. Moreover, thanks to the existence of clear water, agitated and rich in nutrients, various organisms thrived, including numerous colonies of brachiopods. All three types of deposits, subsequently transformed into limestone, today represent the succession of Dachstein Limestone, Grey Limestone and Fanes Encrinite.