Crêt de la Neige
| Crêt de la Neige | ||
|---|---|---|
 Crêt de la Neige (center) |
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| height | 1720 m | |
| location | Ain department , France | |
| Mountains | law | |
| Dominance | 41.3 km → Sous Dine | |
| Notch height | 1260 m ↓ Canal d'Entreroches | |
| Coordinates | 46 ° 16 '21 " N , 5 ° 56' 40" E | |
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| particularities | highest mountain peak in the entire Jura | |
At 1720 m, the Crêt de la Neige is the highest mountain peak in the entire Jura . It belongs to the Haute Chaîne , the easternmost and highest chain of the French Jura, and is located in the Pays de Gex (Département Ain ), around 17 km northwest of the city of Geneva .
The Crêt de la Neige is bounded in the east by the plain of the Pays de Gex and in the west by the valley of the Valserine . The crest of the Crêt de la Neige slopes steeply in these two directions. It rises directly from the plain of the Pays de Gex without a foothill zone and towers over the Geneva basin by around 1300 m. To the southwest the Jura ridge leads directly to the Reculet , to the northeast to the Grand Crêt . A new survey in 2003, carried out by the Institut géographique national (IGN) in Villeurbanne , attested the Crêt de la Neige to an altitude of 1720 m . Previously, the official height was given as 1718 m , which resulted from rounding up the actually measured height of 1717.6 m . The Crêt de la Neige was only 20 cm higher than the neighboring Reculet ( 1717.4 m ). Even earlier it was assumed that the Reculet was the highest mountain in the Jura.
From a structural geological point of view, the Crêt de la Neige forms an anticline of the Jura folds , whereby the rock layers were pushed onto the sediments further to the west at the time of the Jurassic folding in the late Miocene and Pliocene . The anticline is around five kilometers wide at the root and is oriented in the direction south-south-west-north-north-east in accordance with the strike direction of the Jura ranges in this mountain section. The rock material of the Crêt de la Neige comes from marine sediments of the upper Jurassic period (in the crest area mainly the dolomitic limestone of Portlandia and the limestone banks of the Kimmeridgia and Sequania occur) and the Cretaceous period (mainly at the foot of the slope).
Due to the limestone , various karst phenomena could develop on the crest of the Crêt de la Neige . There are numerous cart fields and sinkholes , the rainwater seeps into the porous subsoil and mostly only reappears in karst springs at the foot of the Jura range. That is why the slopes of the Haute Chaîne show very few surface running waters.
In contrast to the rest of the Jura peaks, the crêt de la Neige is not predominantly overgrown with grass in the ridge area, but rather shows a rocky, rugged relief that is partly crossed by small ravines. The mountain has a harsh climate with an annual rainfall of around 2000 mm. In deep, unsunned and wind-protected gaps, the snow can last the whole summer half of the year.
Another specialty of the Crêt de la Neige are the mountain pines growing in the crest area . This robust type of pine, which can be found at altitudes between 1800 m and 2500 m in the Alps, does not occur anywhere else in the Jura. The steep slopes of the Crêt de la Neige are densely forested. Below around 900 m there is mostly deciduous forest, above that up to around 1400 m there is a coniferous forest zone, which in turn is replaced by mountain pastures with subalpine vegetation. The Crêt de la Neige is part of the Haute Chaîne du Jura nature reserve .
Web links
- Crêt de la Neige on GeoFinder.ch