Geological
By Hugh Scortegagna
taken from the" Path Frassati "In the Veneto
ideal path that we follow in this discussion, we will enter into contact with almost all the formations that characterize the Comelico-Sappada. Leaving behind the great mountains of the Group dolomite Popèra, we have before us a green valley, where the curved and rounded shapes of the hills, now covered by forest, indicate that we face in the rocks that can be brittle and or ancient. We know from school knowledge, that the mountains are older and appear to be lower. This is partly true: but we must also take into account the lithology, such as type of rock. In our case, the information you gave us is correct. We are facing mainly from crystalline rocks (metamorphic), consisting predominantly of phyllite and schist. This is the metamorphic basement of pre-Carboniferous (Paleozoic) and represent the oldest rocks in this area, but also of all rocks outcropping in Italy (460M.a. ago). This crystalline basement is what is left to witness Hercynian orogeny. Rounded in the case where less inclined and pendants were placed in residential areas, some as a mirror to Danta Costalissoio, Costalta, etc..
The valley floor, flowing with rather abundant, Piave, is the physical line of separation between the basement metamorphic rocks and sedimentary rocks such as limestone and dolomite that form the backbone of the platform base of the Group of Brentoni and Third. Rocks formed from sediments deposited in the Upper and Middle Triassic, about 200 Mafa. (Mesozoic Era) when the area was an area completely covered with sea water not too deep where living organisms fixers and developers carbonic platforms such as algae, sponges and poor corals. This type of rock with us for everything the first part once you leave the valley, not far from Campolongo. During the descent of St. Stephen can see the sandstone formations known as the Val Gardena (red) and the Bellerophon Formation (dark limestones), which struck on, give off a characteristic odor of bitumen. They are formations that mark the transition between the Age of Primary (Paleozoic) and Secondary (Mesozoic) and are characteristic of a transition environment between the sea and the mainland. The stretch that runs from Sapphire to Val Visdende shows us a place of great charm, while offering panoramic views and landscape relief. It is built along the valley from the waters of the Piave (who was born a little further upstream in the beautiful white pyramid of Peralba) made clear in part metamorphosed limestone of Devonian age (about 400 Mafa) Primary or Palaeozoic Era. At the foot of this "monolith" are terrigenous rocks of Education of the Valley Visdende. This is a typical cytogenetic formation of a marine environment rather deep, consisting of shales, siltstones silver gray-green and brownish gray, laminated and pleated affected by metamorphism of the Carboniferous, a typical training extremely friable and eroded, as to be a predisposing Landscape morphology softer, less structured than the groups that are more to the south. Fabulous views of the upper Val Visdende, where front dominate Mount slab, the ridge of Iron Mountain and Rinaldo formed mainly of limestone for the Landini (Middle Triassic), formed from sediments in a marine environment where the platform was considerable subsidence, thus a considerable vertical growth. These formations are called explicitly Formation of Dolomite and Wefen Serla inf. Two formations, these, which are significant outcrops in this part of the Veneto. In detail the Werfen Formation (247-240 Mafa) consists of marly limestone, grays and blacks and well-stratified oolitic limestones and siltstones alternating red and green sandstone containing the fossils as Claraia Clarae (bivalves) and the cost Naticella (gastropods) . The Dolomite
Serla inf. (240-238 Mafa) consists of dolomite and limestone in color from gray to white, with stratification indistinguishable. In the heart of Val Visdende you look at the mountains of the border, rather homogenized as tree and vegetation cover. A morphological uniformity due to the effect of their lithological nature rather friable and altered-as mentioned above-namely the formation of Val Visdende (Carboniferous Paleozoic) consists of shales and siltstones of deep waters. From the center of the green and lush valley Visdende you look at the complex and uneven Group Longerin mainly formed by limestone, dolomite and Werfen, sarl, Early Triassic, the environment and coastal cliffs. If you walk next to the densely layered outcrops and reddish and dark, you can find the evidence of the wave of battiglia: the classic ripple marks. Now you pass through the formations older than those that form the Crode Longerin, such as those of Val Gardena Sandstone and Bellerophon similar to those encountered by Dante down to Santo Stefano. Here outcrops are masked by a lush vegetation covering the slopes. From Forcella Zovo going down the Col di San Pietro Tamber to fall within the metamorphic basement, is mainly characterized by phyllite. The crossing of the extremely wide Comelico remained in Upper and Lower costs for a long stretch in share, walking over the metamorphic basement of phyllites. In this stretch the view over the valley as a vine is shown in all its grandeur and integrity stands out the broad framework of the mountains of Popera Group, (with lithology formed by limestone and dolomite of Ladin, about 230M.a.fa .) rather tough and hard walls that have high visibility and towering peaks when they were written pages of epic mountaineering Dolomites. The valley floor is covered with a series of moraines, masked by trees and shrubs of great interest. Walk along the wide valley siliciclastic sedimentary deposits from the dismantling of the surrounding mountains, mainly dolomitic limestone of Popera, molded by the ice that covered the valleys and then by water currents. Close to the Baths of Valgrande, positioned at a point that allows us to look beyond the barrier of forest, we can look to the north east, that tower that stands at the end of a grassy woods road which runs parallel to the Val Padola (Costa della Spina) . E 'a treasure of the area, Col Quaterna old volcanic chimney (neck) made a more resistant rock (lava) with respect to his surroundings (the volcano) that with time it is being formed of rocks smaltellato alterable, leaving only the testimony of the central chimney that reaches the altitude 2503m. In addition to the volcanic rocks of the Col Quaterna near the Passo di Monte Croce Comelico you can see one of the most beautiful and extensive outcrops of the sandstones of the Val Gardena (remember the case of red sandstone of fluvial origin arising from the decommissioning of platforms, predominantly volcanic, which emerge to the east, the red color shows, as well as the continental origin, a arid desert).
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