DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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The distinction between Cassian Dolomite 1 and 2 is possible with certainty only where the two
platform tongues are separated by wedges of basin deposits (San Cassiano Formation), as in the case
of the eastern side of the Lagazuoi platform, of the Picco di Vallandro/Dürrenstein, of Cadini di
Misurina and, in a spectacular way, in the area of the Settsass, where the geometrical relationships
between the Cassian reefs and the basin sediments were splendidly illustrated by von Richthofen
(1860). With regard to age, the dating of Cassian Dolomite 1 and 2 is indirect and is achieved
through the calibration of basin deposits on which the platforms prograded or by with which the
platforms are covered.
the Carnian crisis of the rimmed carbonate platforms
Near the end of the Julian the South Alpine area a generalized filling phase of the remaining Carnian
basins occurred. This regressive phase is characterized by a climbing progradation of the Cassian
platforms and by a significant diminution of the clinoform angle. This was counterbalanced by
a decrease in the subsidence, which in the southern sectors led to a strong advancement of the terrigenous
and carbonate coastline (Picotti & Prosser, 1987; Gianolla et alii, 1998a). The complete closure,
the flattening of the paleotopography and the movement of the shoreline dozens and dozens of
kilometers more to the NE occurred with the Heiligkreuz Formation.
The name Heiligkreuz Formation derives from the German Heiligkreuz Schichten that was introduced
by Wissman in Wissman & Munster (1841), but better characterized by Koken (1911) who
described in detail the stratigraphic position and the fauna finds. This term, after being abandoned
and not used for some time, was taken up again by Bosellini et alii (1965) and renamed Santa Croce
Beds. The Heiligkreuz Formation, was named to the definition of Keim et alii (2001), which corresponds
to the Dürrenstein p.p. Formation by Pisa et alii (1980), includes the Dibona Arenites sensu
Bosellini et alii (1982; 1996a) and Neri & Stefani (1998) and corresponds to the Dürrenstein Formation
sensu De Zanche et alii (1993) and successive works (Gianolla et alii 1998a,b; Preto & Hinnov,
2001). The formation is further subdivided into members that document the different filling