Earth Pyramids of Euseigne
Switzerland's first Earthcache!
The Pyramids of Euseigne are the most famous natural landmarks of the Val d'Hérens and the Valais. They are one of the most important geological attraction of the Alps, and are under the protection of the Swiss Confederation.
In the final phase of the last ice age ("Würm glacial stage"), some 80,000 to 10,000 years ago, the Eringer glacier retreat to the south. The glacier split into two major rivers, by which the torrents Dixence and Borgne have been formed. When the ice receded, the side moraines of the both tributary glaciers left a huge amount of boulder behind. In the area of Euseigne this glacier boulder of different origin has pushed together to a heavy medial moraine, which is also including big rock fragments. The moraines at this place have been compressed with high pressure by the 1000m (3300 feet) mass of ice and after the melt of the ice they have been dried out.
This has resulted in voids between the rocks and stones, which gradually filled up with fine grained materials (clay and sand). It formed an extremely hard cemented mixture.
Since the retreat of the ice the vintage moraine material is exposed to the weather, which slowly but steadily slam this waterproof and hard concrete. Rainfall and snowmelt, which superficially trickle over the Moraine, free up more and more the large and resistant boulders. Thanks to their size and their considerable weight these boulders are like "protecting Caps". They compress the underlying material and protect it against the removal by wind and water. The unprotected moraine around crumbles and is gradually washed by wind and water, respectively ground and blown away. This natural erosion process is still in progress. The Pyramids of Euseigne are stately 10-15 meters (33-50 feet) high. Their on pillars sitting stone "caps", consist of massive boulders of several m3 diameter and have up to 20 tons of weight. They are either gneiss (granite Slate) or dark green rock (Serpentinites), carried down by the glacial ice flow from the end of the "Eringertal" or of "Val d 'Hérémence".
==> To log this Earthcache you will have to meet two conditions:
- Visit the Earth-Pyramids and see which beauty nature created here. Study the local information board. There you will also find the answer to the below listed question.
Take a photo of the Pyramids (and you) and attach it to your log.
- Answer the following question:
What is the name of the hard and cemented mixture which formed the Earth-Pyramids in the course of time?
Send your correct answer by e-mail to me: geocaching@phazer.ch
You are allowed to log your found after sending your answers by e-mail. We will get in touch with you if there is something wrong with your answers!
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