logo Museo Paleomtologico

Geologic history of the Dolomites
riga

First part

Second part

The Fossils
riga

Geologic history of the Dolomites - First part

foto The Dolomite mountains surrounding Cortina - and which create scenery unique in the world - are the result of the elevation and folding of large rock masses caused by tremendously powerful tectonic movements.
These phenomena ravaged an area which, about 234 million years ago, was the site of a warm sea, rather like the Caribbean today, dotted with rocks and small islands. One of these was in the Mount Cernera area, where gastropods, branchiopods, algae, sea anemones and characteristic ammonites have been found.

Subsequent volcanic eruptions created numerous islands.
Ongoing erosion produced large quantities of volcaniclastic deposits, dark rocks containing numerous plant fossils, a sign of the presence of tropical forests (230 million years ago).
Later on, evidence of a tropical sea (229 million years ago - Middle Triassic), rich in coral reef, was found in softer rocks such as marl and marl limestone: the so-called "San Cassiano Formation".

After the sea level dropped, large land areas emerged that drastically altered the appearance of the area (225 million years ago): the coral reefs disappeared and extensive flat sea-beds were formed; the sea facilitated the growth of large bivalves and many different species of fish, as well as the appearance of the first land reptiles.
The discovery, not only of animal fossils, but also of coal and amber, testifies to the existence of luxuriant forests.
Subsequently (224 million years ago - Middle Upper Triassic), the level of the sea rose again and, cyclically, covered the land, depositing carbon mud, the Principal Dolomite, that enveloped large lamellibranchs, called megalodonts.

Second part