THE DOLOMITES

VAL GARDENA

UNESCO HERITAGE SITE

A HISTORY
GOING BACK
MILLIONS OF YEARS

The history of the Dolomites can be traced back about 270 M years ago when a vast ocean, the Tethys, separated the African continental plate to the south from the European to the north. In this period, at the edge of the European plate there is a massive volcanic activity which, in the form of “burning clouds”, deposited enormous quantities of ash, lapilli and lava which, once consolidated, gave rise to the rock known today as the porphyry of South Tyrol. On cooled lava, conditions are created for small plants and small, rare reptiles.

The blanket of porphyry, which reached a thickness of up to 2000 meters, then suffered the aggression of the atmospheric agents that pulverized it into a reddish sand. In this region, once the volcanic eruptions ceased, there was a vast plain that extended from Lombardy to Croatia, dotted with torrents, small river basins, and desolate sandy expanses originating from the movement of the debris of the porphyry (255 million years ago) by wind and water The sand created rocks known today as the red sandstone of Val Gardena. The edge of this plain is occasionally flooded by sea waters, creating a favourable habitat for the establishment of rich flora, and fauna of reptiles and amphibians.

At this point, about 240-250 million years ago, is the first real total invasion by the sea. The Tethys, in correspondence to the Dolomites, becomes a vast warm sea, alternating with intervals of occasional emergence of mainland, defined basins, lagoons and low seas in which the rich fauna constitutes an abundant source of nourishment for predatory fish. The arid and warm climate allows for evaporate deposits on the rocks. However, deposits of sediments originating from the erosion processes exerted on the occasionally submerged lands predominate. Barrier reefs and coral ledges were widespread. Deposits of sand, silt, clay, limestone and dolomite rocks are originated in this way, reaching thicknesses of hundreds and, sometimes, thousands of metres.

The question therefore arises of how it was possible to accumulate sediments of such considerable thickness in a sea that maintains very low water, even just a few metres. Seabeds, in general, are subject to sinking that takes place at very different speeds. In the Tethys Sea this process was almost constant and often very rapid. Under such conditions, an increase of any kind of sediment is followed by a lowering of the seabed. The behaviour of coral, marine organisms, is emblematic as they develop in shallow water. In warm sea conditions, growth becomes very rapid but the simultaneous lowering of the seabed sinks coral that can continue to reproduce in the shallowest layers of water.

This period of tranqulllity of the Tethys is interrupted about 240 million years ago when, suddenly, a dramatic and exceptional event occurred. Suddenly over 80% of living organisms die out. Even today it is difficult to trace the cause of such a phenomenon, attributable to a generalized and abrupt climatic variation, with a consequent rapid lowering of the temperature. Such a situation could have been caused by the impact of a large meteorite, able to create such an atmosphere of dust particles so as to prevent the passage of sunlight. After this short dramatic period, the sea returns to dominate on the dolomitic area, with local short regressions during which help proliferate a rich flora and fauna, especially of large terrestrial, marine and flying reptiles, on the mainland. The marine waters are also rich in fish and reptile predators.

This state of substantial tranquillity in the Tethys sea is interrupted between 232 and 223 million years ago after a violent volcanic activity. The Dolomites area is also affected by disturbing volcanic events that produce a huge amount of lava, volcanic tuff, and ashes almost wanting to reinstate the dominance of the internal forces of the earth. In particular, in a sort of competition of unprecedented violence, between the underground and volcanic forces that rival those of the external environment. At the base of the volcanic forces, a formation of sediment is created by subterranean landslides that, slipping along the top of the fault, push themselves a great distance from the place of detachment determining the depositing of sediment, and landslides, also of huge dimensions, in an absolutely chaotic manner, to the point of justifying the name of “Caotico heterogeneous” which was coined to classify this type of rock.

It is interesting to note that Saslong today is in a position quite distant from the one in which the corals that make it up settled. In fact, these sediments were involved in a huge submarine landslide that drove them, along with volcanic debris, miles away from their original position, to exactly where we find them today. After this turbulent period, the Dolomites area experienced a period of tranquillity which lasted until about 100 million years ago when the movement, which then existed between the African Plate and the European one, which was settled, became compressive. This determines the progressive encroachment of the two platforms and the consequent reduction of the sea. The whole series of sediments, from the most diverse origins, deposited in the sea of Tethys is progressively compressed, with the layers folding and rising up while the sea slowly dissipates and eventually disappears.

The European plate is wedged under the African one close to which magmatic injections are activated again (creating Bressanone granite, for example). The dolomitic area is raised and the most recent rocks, the Dolomites, reach the mightiest heights almost as if to emphasize their majesty. It is this, in synthesis, the orogeny of the Alps (that dates back to 20-25 million years ago). It should be reiterated that this is not it the date of birth of the Alps (which dates back to about 250-300 million years) but simply the date of its exposure, of its seeing the light of day. It should also be remembered that the dolomitic rock, which originated from the coral reefs, was constituted originally from calcium carbonate; only later, upon contact with warm waters rich in magnesium, there was the partial substitution of calcium ions with those of magnesium and the rock was transformed into a carbonate double of calcium and magnesium, which is precisely dolomite, name given in honour of its discoverer, Tancrede Gratet de Dolomieu (1750-18019).

From that moment, the emerged lands are subjected to atmospheric action: wind, ice water. Over the last two million years, at least 4 glacial periods have alternated on earth, the last of which ended about 15,000 years ago. The glaciers, with their slow but incessant and powerful movement, shape the valleys according to a U profile that will be subsequently partially modified by rivers. And it is exactly this action, of the glaciers, of the running waters, wind, frost and thaw that are attributed to the form and the chiselled beauty of these wonderful, majestic mountains we have the privilege to admire today.

SASLONG SHOP

Saslong skiwear. Here is a golden opportunity to take away a memory of the Saslong slopes wearing one of our garments that will make you feel like a real champion and above all, one of us—transmitters of the passion that has sparked us in the past few years to make this track one of the most technical, difficult and exciting. Windbreakers, hoodies and hats, all with the Colmar Saslong label. You can order them in our Saslong online shop and receive them directly at home.

SASLONG SHOP

Saslong skiwear. Here is a golden opportunity to take away a memory of the Saslong slopes wearing one of our garments that will make you feel like a real champion and above all, one of us—transmitters of the passion that has sparked us in the past few years to make this track one of the most technical, difficult and exciting. Windbreakers, hoodies and hats, all with the Colmar Saslong label. You can order them in our Saslong online shop and receive them directly at home.

HOTEL SOCHERS

Your high altitude chalet

Located at 2000 metres directly on the ski slopes of the world cup, Hotel Sochers Ski and Spa Resort offers a unique and magical experience in the setting of the Dolomites, a Unesco world heritage site, on the slopes of the majestic Saslong. A special place to spend holidays on the snow and skiing in Val Gardena. Saslong and Hotel Sochers await you for your winter holidays and ski weeks of leisure and entertainment.

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