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This work illustrates the evolution the Lower Jurassic shallow-water carbonates known as the Calcare Massiccio Formation in the Central Apennines (Italy). The Calcare Massiccio is characterized by lateral and vertical variability in the facies associations, related to an articulated physiography of the Triassic to Lower Jurassic carbonate platform and to its tectonic evolution. This work documents the depositional environment changes during the platform evolution. Quantitative analysis on samples collected from three stratigraphic sections were performed through the Calcare Massiccio succession allowed up to the overlying Pliensbachian pelagites. Two type of carbonate sedimentation have been recognized: in the peritidal and shallow subtidal environments (Calcare Massiccio A) the carbonate production is dominated by microbial activity, while the carbonate sedimentation in a deeper environment of middle to outer ramp (Calcare Massiccio B), is dominated by a bioclastic sedimentation. The evolution from the Calcare Massiccio A to the B can be interpreted as the product of increase of accommodation that in turn produced a backstepping of carbonate facies belt, the photic microbial dominated peritidal facies developed on the persistent Latium-Abruzzi Platform while the bioclastic carbonate production factory settled on the structural highs resulting from the dismembering of the platform by syn-sedimentary tectonic. The bioclastic carbonate factory was not efficient in filling the available accommodation space produced by Sinemurian extensional tectonic. This inefficiency was amplified by the restricted area available for this factory in the small structural highs. These conditions were sufficient to predispose the platform to the drowning without invoke change in the trophic resource or change in the palaeoceanography. [ABSTRACT FROM AUTHOR]

The paper deals with original stratigraphic, petrographic and structural data concerning the evolution of the southern Apennines chain (Italy). The main Langhian to Pliocene deposits cropping out in the northern sector of the southern Apennines foreland basin system (Sannio-Irpinia area) have been studied and correlated in order to document the effects of tectonic changes on the evolution of sandstone detrital modes and stratigraphic architecture. The studied sandstone units can be grouped in five key intervals: a) Numidian Flysch, mostly formed by Langhian mature quartzarenitic deposits and conformable Serravallian post-Numidian successions, formed by arkosic and calciclastic arenaceous-pelitic beds (foreland depozones); b) Langhian to Tortonian San Giorgio Fm., mostly composed of quartzofeldspatic sandstones (foredeep depozone); c) Tortonian to Early Messinian, quartz-feldspatic and partly sedimentary-carbonatoclastic petrofacies, thrust-top successions (Vallone Ponticello, Villanova del Battista and San Bartolomeo fms.); d) Late Messinian quartzolithic to quartzofeldspatic sandstones (Torrente Fiumarella, Anzano Molasse and Tufo-Altavilla unit), which can be referred to infilled thrust-top basins; e) unconformity-bounded Pliocene quartzofeldspatic sandstone strata (wedge-top depozones), characterized by synsedimentary tectonic activity. Detrital modes of the Serravallian through Middle Pliocene sandstones of the southern Apennines foreland basin system testify clear provenance relations from the accreted terranes forming the southern Apennine thrust-belt. The studied clastics show almost the same blended (quartz-feldspatic) composition; this condition could be related to the tectonic transport over thrust ramp of source rocks, as suggested by the tectonic evolutionary model. This study, dealing with sedimentary provenance analysis and tectonostratigraphic evolution, provides an example of the close relations between clastic compositions and foreland basin system development in southern Apennines. [ABSTRACT FROM AUTHOR]