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The Jurassic successions of the Furlo area (Northern Marche, Italy) are characterized by complex tectono-stratigraphic relationships related to the extreme differentiation of depositional environments occurring from the early Jurassic. In the area of the future Umbria-Marche Apennines, including the Furlo sector, the Sinemurian tectonic event dismembered the wide peritidal carbonate platform of the Calcare Massiccio Fm. into a series of uplifted and downthrown platform blocks bounded by extensional faults. The subsequent drowning of these blocks led to the development of two main environments: pelagic carbonate platforms and basins. The present paper focuses on an analysis of facies that characterize some paleogeographic sectors connecting these two different environments in order to understand the role of tectonics as a control on sedimentary processes. In these sectors, different types of facies have been identified and interpreted. Relationships between facies types, their stacking pattern, and sedimentary structures enabled the identification of different depositional processes directly or indirectly controlled by the tectonic evolution of the study area. The data compiled, compared with those from the literature, were used to relate the Furlo area to a general pelagic carbonate ramp environment constituted by two tilted and drowned carbonate platform blocks; these originated as a result of early Jurassic tectonic activity characterized by some approximately perpendicular faults showing a prevailing rotational character. [ABSTRACT FROM AUTHOR]

The space/time evolution of the Umbria-Romagna-Marche domains of the northern Apennine Miocene foredeep is proposed. In this period, the turbidite siliciclastic sedimentation is represented mainly by the Miocene Marnoso-Arenacea Formation, which generally ends with mainly marly deposits. From the internal Apennine sectors (Umbria-Romagna domain) to the external Adriatic Margin (Marche domain) the siliciclastic succession overlies hemipelagic marly deposits (Schlier Formation). The whole depositional area can be considered as a single wide basin with depocenter or main sedimentation areas progressively migrating eastwards. This basin is characterized by some morphological highs which did not constitute real dams for the sedimentary flows (turbidity currents). Multiple feeding (arkose, litharenites, calcarenites) from different sources is related to palaeogeographical and palaeotectonic reorganization of the most internal, previously deformed, Apennine areas. The activation of the foredeep stage is marked by the beginning of the siliciclastic sedimentation (Late Burdigalian in the most internal sector). This sedimentation ends in the most external sector in the Early Messinian, pointing to a depositional cycle of about 9–10 Ma. The diachronism of the base of the siliciclastic deposition proves to be almost 5 Ma. The syn-depositional compressional deformation, which shows a marked diachronism, affected the internal area of the foredeep in the Early-Middle Serravallian, and progressively migrated up to Late Miocene, involving more and more external sectors. The deformed siliciclastic sedimentary wedge constitutes an orogenic pile incorporated in the Apennine Chain, represented by different tectonic elements superimposed by means of NE-vergent thrusts. The main stratigraphic and tectonic events of the Toscana-Romagna-Marche Apennines are presented in a general framework, resulting also in a terminological revision. [ABSTRACT FROM AUTHOR]