Fig. 5

Field aspect of the meta-sediments within the Pinerolo Unit: conglomerate-sandstone succession with interbedded graphite layers (gr = graphite layer). In the stratigraphic log the reported thickness of the layers is the one measured on the outcrop and, thus, represents the thickness after the Alpine strain. White, yellow and grey ovals represent quartz-, feldspar- and graphite-rich pebbles, respectively. a b Outcrop aspect consisting of cliffs (a few metres thick) separated by ledges in correspondence of graphite layers, interpreted as resulting from a cyclic sedimentation. c Interbedded meta-conglomerates and meta-sandstones. d Polygenic meta-conglomerates with centimetre- to decimetre-sized pebbles of graphite-rich schist, interpreted as original clay chips, and centimetre-sized pebbles of quartz and felsic gneiss. e Graphite layer at the base of thick sandstone layer. a d Lat/long coordinates 44° 59′ 31.9′′ N–7° 07′ 05.3′′ E. b c e Lat/long coordinates 44° 59′ 32.3′′ N–7° 07′ 06.8′′ E