From the geological point of view the area of the park is the result of subsequent formations which date back to very different centuries. The most antique rocks are porphyries of volcanic origin. Then the erosion of elevated porphyries blocks originated sedimentary rocks. Geological researches supposed the existence of a wide sea basin (Tetide), which, between the Primary era and the secondary one, had started off great phenomenon of sedimentation. With their end, datable about 38 million years ago, the alpine orogenesis began which still last.

The alternation of rocks from eruptive origin (porphyries) and from sedimentary origin (limestone) allowed the formation of narrow valleys, one leaning against the other, which culminate in the Marguareis Valley.

Here you can still find recognizable ruins of the glacial formations (moraines), core samples of the last activity phases.