DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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Stratigraphical correlations among
some Heiligkreuz Fm sections, showing
the important lateral variation of this
formation. HKS-Heiligkreuz Fm;
DCS-Cassian Dolomite; SCS-San
Cassiano Fm; TVZ-Travenanzes Fm.
(Mod. from Preto & Hinnov, 2003
and Stefani et alii, 2004).
Upper triassic carbonate platform: a regional peritidal succession
The deposits of the Upper Carnian and of the Norian are indicative of a significant reorganization
of the paleogeography of the future Alpine area (Bosellini, 1973). While the Anisian-Carnian break
is characterized, in the area of the Dolomites, by an extreme environmental variability, even at short
range, probably controlled by synsedimentary tectonic activity, with the Upper Carnian/ Norian a
paleogeographic pattern characterized by slow and gradual lateral variations is established. At the
time of the deposition of the Dolomia Principale, the entire South Alpine realm was incorporated
into a peritidal depositional system, with wide lagoons and tidal plains that extended for hundreds
of kilometers both in a north-south and in an east-west direction. The dry lands were localized to the
south and to the southwest (e.g. the German Trias of Sardinia). The platform margin and the passage
to the open sea are documented in the Tarvisio area (Gianolla et alii, 2002) and in Dachstein Kalk of
the upper Austro-Alpine slabs. However, notwithstanding this contest characterized by a large-scale
homogeneity of the environments, one can recognize and distinguish more lithostratigraphic units.
With the definitive filling of the ancient marine basins, the region again became a vast coastal plain.
On this plain took place the slow deposition of carbonate sediments mixed with deposits of conti-