les stalactites
les stalagmites
les colonnes et les piliers
les disques de calcite
les fistuleuses
les draperies
Les méduses
les excentriques
Questions:
1/ Expliquez comment se forme une grotte calcaire.
2/ Allez dans la grotte (passer sur le petit pont) et identifiez les concrétions que vous y trouvez!
Vous pouvez joindre à votre log une photo de vous dans ou au abords de la grotte.
This cache is designed to introduce you to a nice cave in the gorge of the Doubs to .
Attention access is dangerous because it takes up a rather high level ( about 7/8m high). You will engage your own risk.
Type of caves are distinguished different
The caves dug under a slab of basalt. The soil was washed away by erosion , leaving a void beneath the crust of basalt deposited by a volcano ;
The caves developing in the interstices of a granitic chaos. The granitic rocks are altered by the action of rain and granite balls can form up to several meters in diameter. Natural stack of these balls form a chaos ;
The caves carved in granite and gneiss . Formed in the mass of granite by dissolution phenomena , these caves are rare and very original .
And finally limestone caves .
In limestone caves we find different formations :
Concretions are generally crystalline chemical deposits due to the precipitation of salts dissolved in water and this form of calcite , aragonite more rarely , and sometimes gypsum.
Concretions can take many shapes and colors.
- Stalactites
- Stalagmites
- Columns and pillars
- Hard calcite
- Fistula
- Draperies
- Jellyfish
- Eccentric
Questions:
1 / Explain how to form a limestone cave.
2 / Go into the cave (go over the small bridge ) and identify the concretions that you find !
You can join a picture of you in or out the cave.