Folungo-Monte Bavarione Pass

As you walk along the road (closed to private cars) that circles Monte Bavarione from Passo Folungo, you can seean almost continuous display of all the rock types found in the Strona-Ceneri area.

The first outcrop consists of flaser gneiss, a strongly laminated augengneiss. Then, over a long stretch, we find the ‘Gneiss Minuti’, a fine-grained gneiss with beautiful, similar folds and calc-silicate nodules. Before reaching the southern end of the road, we come across an orthogneiss intercalated with the Gneiss Minuti. Over the final few tens of metres, the outcrops almost disappear because the rocks retain a pre-glacial weathering crust, which transforms the quartz-feldspar rocks into coarse residual sand. An unaltered mafic dyke cuts through the rocks; its intrusion certainly occurred after the metamorphism and is therefore most likely of Permian age (around 270 million years). The dyke cuts across the contact between the orthogneiss and the Ceneri gneiss. The latter is exposed in a number of rounded boulders preserved from erosion. Some well-zoned calc-silicate nodules and quartz pebbles can be observed. The remains of this deep alteration, probably of Pliocene age, are visible only on the southern slopes, as they were situated on the leeward side of the Lake Maggiore glacier, which flowed from the north. On the northern slopes, the sandy rock cover was eroded away by the glacier.