DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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Direct dating of the Sciliar platforms is related to sporadic findings of ammonites on the slopes or in
tempestite within sediment traps in the inner lagoon (Gaetani et alii, 1981; Brack & Rieber, 1993;
Preto et alii, 2001; Zühlke et alii, 2003). Indirectly it is possible to define the age of the platforms
with precision by dating the heteropic basin facies or the drowning facies accompanying them. The
‘Dolomia dello Sciliar’ includes between the Upper Anisian and the Ladinian.
As has already been pointed out, the heteropic basin deposits with the carbonate platforms are
known as Buchenstein Formation or Livinallongo Formation. The unit corresponds to Buchensteiner
Schichten of Richthofen (1860) named after a locality (Buchenstein Schloss now Castello di Andraz)
in a lateral valley of the Torrente Cordevole near Pieve di Livinallongo. Subsequently, Mojsisovics
(1879) enlarged and generalized the stratigraphic interval, subdividing the formation, from bottom
to top, into three units separated by nodular limestones with volcaniclastic intercalations (‘‘Pietra
Verde’’): the lower Bänderkalke, the Plattenkalke and the upper Bänderkalke. The lower level was then
successively renamed Plattenkalke (Ogilvie-Gordon, 1929). The Buchenstein Formation comprises
an alternation of nodular and cherty micritic limestones, of bituminous limestone laminites, of volcano-detritic
turbidities and of pyroclastics deposited in relatively deep basins and characterized by
certain homogeneity of depositional style as well as by a large distribution area (Brack & Muttoni,
2000).
800-900m
40°
Sciliar Dm
Buchenstein Fm
Morbiac Lm
Contrin Fm
Depositional geometries amazingly preserved at the Catinaccio/Rosengarten platform.
As has been stated, the Buchenstein Formation is traditionally subdivided into three units that are,
from the bottom: Plattenkalke, Knollenkalke and Bänderkalke:
a) Plattenkalke – comprises bituminous rhythmites, finely laminated black calcilutites rich in pelagic
bivalves, dark micritic limestone, sometimes massive, but normally with parallel lamination.
There are also bituminous dolomitic limestones, with plane-parallel bedding, and bituminous
dolosiltites. The Plattenkalke are mainly characterized by siliciclastic and carbonate microturbiditic
laminas (Maurer et alii, 2003). The bioturbation is normally absent in the lower part