The Alps formed when the African and Eurasian tectonic plates slowly collided, pushing up the ground over millions of years. However, the present-day mountainous landscape is also the result of succeeding millions of years of glacial activity and erosion.
About 60 Million years ago the Alps were still under water. This is the reason why so much of the rock found in the Alps is formed of sedimentary limestone.
The basis of the Large Mythen is made of grayish Malm limestone. The top consists of reddish Couches Rouges [reddish limestone from the Cretaceous period] which consists of myriads of small calcareous shells of microorganisms, which have lived in the primordial sea. The red color originates from ferrous minerals.
Researchers have found out that the reddish cap of the Large Mythen is much older [200 million years] than its grayish basis [50 million years]. How can this be explained? One would have expected a layer of younger stones on older stones and not vice versa.
According to today’s knowledge the reddish Couches Rouges is the sediment of an earlier ocean in the region of Italy and Spain. It was pushed north during the formation of the alps and came to rest on the mountains in the Mythen area. Thus, the Large Mythen is an ancient Spaniard. Interesting, isn’t it!