Useful Info * Dolomites
GENESIS OF THE DOLOMITES
The geological history can be traced back at least 280 million years ago, when an intense volcanic activity disrupted the whole territory of the Trentino South Tyrol area. Lava, tuff and volcanic products rapidly filled and sometimes buried the region; in particular..
.. in the valley basin of Bolzano these volcanic products exceeded 2 meters in height. It formed the athesina porphyria platform, the widest formation of quartz porphyry in Europe (perhaps in the world) with an extension of 1544 square miles, from the Meran valley to the Valsugana. 250 million years ago, the sands, produced by the erosion of the porphyry and deposited along the banks of the streams and the lakes, petrified and formed the Sandstones of the Gardena Valley: the first sedimentary formation is still recognisable in Ortisei, S.Anna Valley, Carezza, Passo delle Erbe, Nova Ponente, Passo Valles and in the Bletterbach–Butterloch canyon.
The slow sinking process gradually allowed to the Sea of Thetis to invade and to form lagoon’s waters, rich of marine organism that due to the torrid climate quickly evaporated. So, clay and sludge were deposited over the Gardena’s sandstone, and they gave shape to layers of plaster and limestone. These are the layers of Bellerophon, named after the marine gastropod that inhabited the seabed. In these layers you can find several fossils of the Bellerophon snail. The layers of Bellerophon mark the boundary between the Permian of the Palaeozoic era and the Triassic of the Mesozoic era. The bounder between the Palaeozoic and the Mesozoic can be marked by the signs of a period of natural disasters or of a huge event that caused the extinction of most living beings on earth.
At the beginning of the Mesozoic era, 248 million years ago, the sea of Thetis had advanced up to France. The sea deposit increased for the continuous supply of thinner materials from the rivers that descended the ancient mountains. These sedimentary masses, rich in fossils and different colours, are the layers of Werfen (visible along the sides of the Catinaccio, in the Bletterbach– Butterloch canyon, in the Funes Valley, the Passo Rolle and Passo Valles).
The seabed was populated with calcareous algae and with the cementation of their shells, an extensive rock bank (2,75in thick) was formed and called Dolomia of the Serla and Calcare of the Contrin. The Dolomia of the Serla belts the western slope of the Catinaccio and reappears further south at the top of the Corno Bianco.
During the Ladinian time, 235 million years ago, violent earthquakes disrupted the seabed. The parts closest to the surface of the rock bank of the Dolomia of the Serla became a solid base for sponges, calcareous algae and corals that proliferated favoured by the ideal conditions of salinity, clarity and temperature of the water. In a few million years, the rocky bank (even more than 229,65ft height), known as Dolomite of the Sciliar and Limestone of the Marmolada and of the Latemar, was raised.
The first includes the rock of the Sciliar, Catinaccio, Sasso Lungo, Sasso Piatto, Sass Pordoi, Odle, Pale of San Martino and the lower eastern central Dolomites including the Sella. The second includes the Marmolada and the Latemar.
A new change in the environmental conditions stopped the growth of the coral reefs. There followed, for a long time, deposits of sandstone and clay of various colours of the Layers of Raibl that gave shape to the characteristic ledges of the Sella–Sass Pordoi Group and of the Sassongher as well as to the reddish stratifications on top of the Sciliar.
The environment consisting of shallow water, lagoons and strips of earth gradually transformed into a vast esplanade subjected to periodic advances and sea retreats. From the different sediments superimposed in millions of years, due to sea fluctuations, was originated the Main Dolomite, thickly stratified and that constitutes the highest parts of the Sella–Sass Pordoi–Sassongher Group, of the Monte Castello, the Monte Pez on the Sciliar and many peaks of the Eastern Dolomites: Tofane, Conturines, Lagazuoi, Pelmo, Civetta, Antelao, Cristallo, Sorapis, Marmarole, the famous Tre Cime di Lavaredo and, further west, the Tribulaun, the Ortles, the Gran Zebrù and the Dolomite of Brenta.
During the Jurassic period, between 200 and 180 million years ago, the waters became deeper and the Dolomitic area became a submerged platform on which the grey limestone’s settled (Fanes). The platform sank up 3280,84ft below the surface and at that depth the red limestone deposited (Puez, Fanes, Sennes, Fosses).
During the Cretaceous period, 120 million years ago, on the north of the Dolomite belt, long strips of earth began to emerge. The particles eroded by these lands deposited on the limestone forming the Marne of the Puez.At the end of the Cretaceous period, 65 million years ago, the Dolomites were still submerged. The first peaks of Dolomites rose 20-30 million years ago from the Tethys Sea. As soon as they emerged erosion came into action; erosion that first freed the tops from the mass of material. Then it was the turn of the limestone and dolomite platforms that were filed, flattened and split. The subsequent glaciations between 1,000 and 12,000 years ago, contributed to sculpting the Dolomite landscape characterized by gentle slopes, alpine plateaus and towering towers and spires that we can admire today.
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The slow sinking process gradually allowed to the Sea of Thetis to invade and to form lagoon’s waters, rich of marine organism that due to the torrid climate quickly evaporated. So, clay and sludge were deposited over the Gardena’s sandstone, and they gave shape to layers of plaster and limestone. These are the layers of Bellerophon, named after the marine gastropod that inhabited the seabed. In these layers you can find several fossils of the Bellerophon snail. The layers of Bellerophon mark the boundary between the Permian of the Palaeozoic era and the Triassic of the Mesozoic era. The bounder between the Palaeozoic and the Mesozoic can be marked by the signs of a period of natural disasters or of a huge event that caused the extinction of most living beings on earth.
At the beginning of the Mesozoic era, 248 million years ago, the sea of Thetis had advanced up to France. The sea deposit increased for the continuous supply of thinner materials from the rivers that descended the ancient mountains. These sedimentary masses, rich in fossils and different colours, are the layers of Werfen (visible along the sides of the Catinaccio, in the Bletterbach– Butterloch canyon, in the Funes Valley, the Passo Rolle and Passo Valles).
The seabed was populated with calcareous algae and with the cementation of their shells, an extensive rock bank (2,75in thick) was formed and called Dolomia of the Serla and Calcare of the Contrin. The Dolomia of the Serla belts the western slope of the Catinaccio and reappears further south at the top of the Corno Bianco.
During the Ladinian time, 235 million years ago, violent earthquakes disrupted the seabed. The parts closest to the surface of the rock bank of the Dolomia of the Serla became a solid base for sponges, calcareous algae and corals that proliferated favoured by the ideal conditions of salinity, clarity and temperature of the water. In a few million years, the rocky bank (even more than 229,65ft height), known as Dolomite of the Sciliar and Limestone of the Marmolada and of the Latemar, was raised.
The first includes the rock of the Sciliar, Catinaccio, Sasso Lungo, Sasso Piatto, Sass Pordoi, Odle, Pale of San Martino and the lower eastern central Dolomites including the Sella. The second includes the Marmolada and the Latemar.
A new change in the environmental conditions stopped the growth of the coral reefs. There followed, for a long time, deposits of sandstone and clay of various colours of the Layers of Raibl that gave shape to the characteristic ledges of the Sella–Sass Pordoi Group and of the Sassongher as well as to the reddish stratifications on top of the Sciliar.
The environment consisting of shallow water, lagoons and strips of earth gradually transformed into a vast esplanade subjected to periodic advances and sea retreats. From the different sediments superimposed in millions of years, due to sea fluctuations, was originated the Main Dolomite, thickly stratified and that constitutes the highest parts of the Sella–Sass Pordoi–Sassongher Group, of the Monte Castello, the Monte Pez on the Sciliar and many peaks of the Eastern Dolomites: Tofane, Conturines, Lagazuoi, Pelmo, Civetta, Antelao, Cristallo, Sorapis, Marmarole, the famous Tre Cime di Lavaredo and, further west, the Tribulaun, the Ortles, the Gran Zebrù and the Dolomite of Brenta.
During the Jurassic period, between 200 and 180 million years ago, the waters became deeper and the Dolomitic area became a submerged platform on which the grey limestone’s settled (Fanes). The platform sank up 3280,84ft below the surface and at that depth the red limestone deposited (Puez, Fanes, Sennes, Fosses).
During the Cretaceous period, 120 million years ago, on the north of the Dolomite belt, long strips of earth began to emerge. The particles eroded by these lands deposited on the limestone forming the Marne of the Puez.At the end of the Cretaceous period, 65 million years ago, the Dolomites were still submerged. The first peaks of Dolomites rose 20-30 million years ago from the Tethys Sea. As soon as they emerged erosion came into action; erosion that first freed the tops from the mass of material. Then it was the turn of the limestone and dolomite platforms that were filed, flattened and split. The subsequent glaciations between 1,000 and 12,000 years ago, contributed to sculpting the Dolomite landscape characterized by gentle slopes, alpine plateaus and towering towers and spires that we can admire today.
