In the Giogo-Casaglia complex, we find three different rock formations that give rise to diversified landscapes that are typical of Upper Mugello: from the softer, rounded slopes that are typical of Chaos Terrain Formation, to those that are more rugged and almost Alpine in shape, typical of the Cervarola-Falterona formation and the Marnoso-Arenacea formation. The different characteristics of the rocks result in substantially diverse landscapes.
It is, however, sedimentary rock, formed at the bottom of the sea by the sedimentation of sand and silt from the erosion brought on by streams and rivers.
The Cervarola-Fanterona and the Marnoso- Arenacea rock formations, that characterize most part of the territory, were formed thanks to the long sedimentation process; the first, in the early and middle Miocene periods (roughly 21-18 million years ago), was formed by detritus from the erosion of the Apennines chain in formation.
The Marmoso-Arenacea creates landscapes made up of valleys and deep slopes that were carved by the waters, giving it a typical canyon aspect, as can be seen in the Rovigo Valley.