Summit of the Aiguillettes
The Aiguillettes summit and its breathtaking 360° view.
To the south, the Eau d'Olle valley, with the Grand Galbert, in the distance the Vercors massif, to the west the Belledonne massif, then the Aiguilles de l'Argentière to the north west, to the north the Lauzières, the Mont Blanc, to the north east, the grandes Rousses and the main summits Pic de l'Etendard, Pic Bayle, Pic Blanc.
If you look at the Grandes Rousses massif, which is made up of gneiss and granite, and the Rissiou massif, a crystalline massif (gneiss), you can see that the nature of the rocks in the Aiguillettes is different.
The Aiguillettes du Couard, or Vaujany, are a geological curiosity in their own right. The gullying has exposed the layers of the sedimentary cover, a very thick layer, and erosion has revealed the folds.
These needles are a large millefeuille composed of limestone and clay. The presence of fossils makes it possible to date them to the Jurassic period (180 million years ago). Limestone is a sedimentary rock. To understand where these rocks come from, you will need to use your imagination. Erasing what you have in front of you... replace it by a sea, at the bottom of which there are fish, crustaceans, shells, the warm seas of the tropics for example. The remains of the skeletons and shells of these living beings are deposited on the bottom of this sea.
The limestone of the needles appears black...but why? The black colour is due to the organic matter of the living beings whose flesh did not decompose on the bottom of the sea due to lack of oxygen. This organic matter then became oil...yes, you read that right!...so if the Alps hadn't appeared and the sea was still covering our landscapes, Vaujany could have been the site of an "off shore" operation. But the movement of the plates decided otherwise, in the middle of a subduction zone between the Eurasian and African plates, the Alps chain was formed and the oil heated up, transformed into gas and escaped. Today, only the black colour remains from the dyeing of the limestone. Now, if we look at the shape of the Agulhas, we can see two things: folds and a well-marked laminate. It is the clay interposed between the limestones, a soft rock that has allowed the structure of the Agulhas to be folded under strong pressure and compression.
At the end of your hike, take some time at the Collet, a leisure spot in Vaujany, where you will find a restaurant and bar. From there, you will be at the foot of the Aiguillettes and will be able to admire this spectacular setting.
From the summit you have several options:
- option 1: go back down by the same route
- option 2: return to the Col du Couard, follow the path down to the Col du Couard, then return by the same route. The col du couard is very beautiful, and the back of Aiguilles is very wild. A great way to extend the hike. Count 40 minutes of descent and 50 to go back up.
En pratique
Services
- Pets welcome
Tarifs
Free of charge.
Information mise à jour le 10/04/2024
par Office de Tourisme de Vaujany