ABSTRACT:Wereport the first high resolution bio-magneto and cyclostratigraphical study on Messinian pre-evaporitic marine deposits (Gello Composite Section) from the Volterra Basin (Italy). Since the investigated deposits manifest no evident lithological cyclicity, cyclostratigraphical analyses have been based on: i) abundance fluctuations of Bolivina and Bulimina among the benthic foraminifera, Globigerinoides, Orbulina and Turborotalita among the planktonics; ii) CaCO3 content changes; and iii) Shannon-Weaver index variations relative to benthic assemblages. As a result, 19 precession-controlled cycles have been recognized.Moreover, the recognition of the C3An.1r, C3An.1n and C3rmagnetozone and some bio-chronohorizons, have allowed the tuning of the studied sectionwith theATNTS (Astronomical TunedNeogene Time Scale) using the La2004 solution of the insolation curve. Thismultidisciplinary study strongly supports that the onset of evaporitic deposition in Tuscany and in other circum-Mediterranean type-successions, as theAbad Composite Section (Spain) and the Falconara Section (Sicily), was isochronous.