DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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sometimes they are organized into FU cycles with alternating reddish conglomerates-pelites. Bodies
of breccias, reddish sandstones and argillaceous siltites are sometimes present. Predominant towards
the top are the arenaceous dolomites and dolomitic siltites with ripple-crossed lamination that document
the passage from a braided river system to marginal coastal and marine environments. The lagoons,
sites of intense evaporation, usually alternated with tidal planes of carbonate sedimentation,
influenced sometimes by continental terrigenous sediments in which proliferated extensive prairies
of crinoids and algae (Gracilis Formation). However, in the more subsident areas, deep lagoons were
formed (Coll’Alto Dark Limestone and the lower part of the Dont Formation) with some bioconstructed
carbonate platforms (Monte Rite Formation). The Coll’Alto Dark Limestone is mostly
made up of dark, almost black, slightly fetid limestones, of gray dolomitic limestones and of bioclastic
calcarenites with algae and the remnants of echinoderms. The strata are of variable thickness
ranging from centimeters to decimeters, with plane-parallel to slightly wavy boundaries. Towards the
top the stratification gradually increases in thickness and passes over to light or crystalline gray dolomites
from poorly stratified to massive, that gradually transition to the Monte Rite Formation. The
fossiliferous associations are characterized by algae, foraminifers, ostracods, bivalves, gastropods, brachiopods
and fragments of echinoderms.
The carbonate bank of the Contrin Formation and the Sciliar/Schlern carbonate platform.