• journal_title：Bollettino della Societa Geologica Italiana
• Contributor：Marco Delle Rose ; Francesco Guerrera ; Alberto Renzulli ; Livia Ravasz-Barnyai ; Francisco Serrano
• Publisher：The Electrochemical Society
• Date：1994-
• Format：text/html
• Language：en
• journal_abbrev：Bollettino della Societa Geologica Italiana
• issn：2038-1719
• volume：113
• issue：3
• firstpage：675
• section：Sedimentary petrology

A review of the "Marne di Vicchio" (Auct.) is proposed, according to the space-time reconstruction of important lithostratigraphic, biostratigraphic and volcaniclastic events within the sector of the investigated basin. The whole succession can be divided in 4 stratigraphic intervals, the first of which is made up of the uppermost part of the Falterona Formation; the second and third representing the "Marne di Vicchio" s.s.; the fourth making up an independent unit. The recognized lateral variations, probably increased by tectonic elisions, are referred to a palaeotopographic control. In the studied area, the "Marne di Vicchio" s.s. sedimentation occurred, without interruption, on not tectonized basin deposits belonging to the late Aquitanian (top of interval I). It is mainly represented by marls, cherry limestones and tuffaceous sandstones, with the palaeoecological data that seem to indicate a lower slope environment. After a hiatus of about 1,0-1,5 Ma during Langhian p.p., the different facies of the interval IV, constituted by marly-arenaceous turbidites (subarkose), marls-calcareous turbidites (hybrid) hemipelagites and slumps, are consistent with a basin environment. The uppermost levels of this interval, directly underlying the Liguride Complex, belong to the middle Serravallian. The volcaniclastic supply is the result of contemporaneous explosive eruptions with rhyolitic-dacitic compositions and mainly distributed in two time periods: (a) late Aquitanian p.p.-early Burdigalian p.p. (at about 22,0-20,5 Ma) and (b) early Burdigalian p.p.-late Burdigalian p.p. (at about 19,5-18,0 Ma). The volcanogenic sediments are linked to the evolutive stages of an orogenic magmatic cycle with a calc-alkaline volcanism (High Potassium to Shoshonitic). Most of the tuffaceous sandstones seem to have been originated by volcanic material epiclastically-transported by sediment gravity flows shortly after its pyroclastic fragmentations. The provenance of this unwelded pyroclastic material would be the steep and unstable margins of a volcanic system. The main supply (subarkose, hybrid, volcaniclastic and particular marker beds) recognized in the external sector of the Falterona-Vicchio Basin during Aquitanian to Serravallian age came out from different sources. The latter can be correlated with the coeval corresponding supply determined in the more external Umbro-Romagnolo and Umbro-Marchigiano basins.