The gaps in the Middle-Upper Cretaceous carbonate series of the southern Apennines (Abruzzi and Campania Regions)

Abstract

The results of the study of some discontinuities within the Middle-Upper Cretaceous series in Abruzzi (Monti d'Ocre and Western Marsica) and Campania (Caserta Mountains) are reported. The microbiostratigraphic study allowed to definethe extension of the gaps found between the Upper Albian and the Turonian-Lower Senonian. Two gaps are present in most of the series analysed so far. The lower gap, generally indicated by the presence of bauxitic deposits, extends from the Upper Albian to the Lower part of the Middle Cenomanian in all the studied areas. The upper gap is indicated by one or several beds of red breccias, in the Abruzzi area, and by a thin bauxitic deposit associated with red breccias, in the Western Campania. The normal sedimentation begin again during the Upper Turonian in the Abruzzi area and during the Lower Senonian in the Western Campania area. These gaps possibly reflect emerging episodes of the carbonate platform. In the Haq, Hardenbol & Vail (1987) curve of relative sealevel variations, the upper gap can be correlated with the Turonian fluctuations of sealevel, but the lower gap corresponds to the general rising of sealevel during the Cenomanian. If the already mentioned scheme is also valid for the Tethyan area, other local causes, probably according to tectonic events, should be looked for to explain this first emerging episode in the Central-Southern Apennines.