The working area is situated in the Monticiano-Roccastrada Zone, an interfering metamorphic core complex of Tertiary age - constituent of the Mid Tuscan Ridge - , where subduction-related, blueschist facies metamorphosed siliciclastics (350-400°C, 0.7-1.1GPa) are exposed. Geological survey at the 1:10.000 scale resulted in the differentiation of tectono-stratigraphically homogeneous subzones, characterised by distinctive Carboniferous lithofacies as well as Tertiary-Quaternary deformation and metamorphism. The stratigraphic base of each subzone consists of a condensed, fossil-poor sequence, deposited in an epicontinental, shallow marine, starved, dysoxic to anoxic basin (Late Emsian - Early Carboniferous). It is supposed that the depositional conditions in this basin were influenced by palaeoenvironmental crises. Its Early Carboniferous extensional fragmentation - interpreted as marine failed rift event - resulted in the formation of different coeval, predominantly siliciclastic depositional areas forming a highstand systems tract above a downlap surface. The proximality trend is - in recent coordinates - westbound and the discerned sedimentary environments, separated by normal faults, consist in the inner shelf, outer shelf, lower slope, base of slope and basin margin. The sudden onset of this mass-flux was probably connected with the Hangenberg Event. Deposition of these fossil-poor sediments occurred under hothouse conditions and was influenced by tropical storms, which generated tempestites and triggered turbidites, bypassing the outer shelf sediments. Rare brachiopods sampled from there resulted in the identification of Antiquatonia Miloradovich, 1945 (Viséan-Serpukhovian). The formations were covered by regressive, littoral-deltaic siliciclastics (Permian - Early Triassic) and the Verrucano Group (?Middle Triassic).