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The Provençal and Dauphinois Mesozoic successions cropping out at the southeastern margin of the Argentera Massif (Maritime Alps, NW Italy) were deposited at the transition between the Provençal platform and the Dauphinois basin, marked in the study area by a partly preserved Mesozoic palaeoescarpment. These successions show important lateral variations occurring over relatively short distances, probably related to syndepositional tectonics. Different stratigraphic intervals of the pelagic-hemipelagic Dauphinois succession contain resedimented deposits, made up of both intra- and extrabasinal material, which provide a twofold evidence of syndepositional tectonics indicating both tectonically-triggered gravitational processes and a tectonically-driven evolution of the source areas. Two stages of syndepositional tectonics have been recognized: the first in the earliest Cretaceous, which is related to the deposition of carbonate breccias in the Dauphinois succession and to hydrothermal dolomitization of the Middle Triassic-Jurassic Provençal carbonates, and the second in the Late Cretaceous, which triggered the deposition of different detrital lithozones in the Upper Cretaceous Puriac Limestone. The cited evidence indicates that syndepositional tectonics continued to influence the evolution of the Alpine Tethys European passive margin long after the Late Triassic-Early Jurassic syn-rift stage, which caused the differentiation between the Dauphinois basin and the Provençal platform.

The Provençal and Dauphinois Mesozoic successions cropping out at the southeastern margin of the Argentera Massif (Maritime Alps, NW Italy) were deposited at the transition between the Provençal platform and the Dauphinois basin, marked in the study area by a partly preserved Mesozoic palaeoescarpment. These successions show important lateral variations occurring over relatively short distances, probably related to syndepositional tectonics. Different stratigraphic intervals of the pelagic-hemipelagic Dauphinois succession contain resedimented deposits, made up of both intra- and extrabasinal material, which provide a twofold evidence of syndepositional tectonics indicating both tectonically-triggered gravitational processes and a tectonically-driven evolution of the source areas. Two stages of syndepositional tectonics have been recognized: the first in the earliest Cretaceous, which is related to the deposition of carbonate breccias in the Dauphinois succession and to hydrothermal dolomitization of the Middle Triassic-Jurassic Provençal carbonates, and the second in the Late Cretaceous, which triggered the deposition of different detrital lithozones in the Upper Cretaceous Puriac Limestone. The cited evidence indicates that syndepositional tectonics continued to influence the evolution of the Alpine Tethys European passive margin long after the Late Triassic-Early Jurassic syn-rift stage, which caused the differentiation between the Dauphinois basin and the Provençal platform. [ABSTRACT FROM AUTHOR]

The Trucco Formation and the Nummulitic Limestone (Dauphinois Domain, Maritime Alps) are characterized by abundant larger foraminifera, specifically nummulitids, orthophragminids and encrusting foraminifera. In the Maritime Alps, previous studies suggest a late Lutetian age for the Trucco Formation and a late Lutetian-Priabonian age for the Nummulitic Limestone. Biostratigraphic analysis of the nummulitids, in 11 stratigraphic sections, allowed us to distinguish 3 biozones: MALF1 Zone: defined by the presence of Nummulites brongniarti d’Archiac & Haime, N. puschi d’Archiac, N. perforatus de Montfort, N. striatus (Bruguière), N. cf. dufrenoyi d’Archiac & Haime, N. variolarius/incrassatus and Operculina schwageri Silvestri. MALF2 Zone: defined by the presence of Nummulites perforatus de Montfort, N. striatus (Bruguière), N. cf. dufrenoyi d’Archiac & Haime, N. variolarius/incrassatus and Operculina schwageri Silvestri. MALF 3 Zone: defined by the presence of gr. Nummulites variolarius/incrassatus, N. striatus (Bruguière) and Operculina schwageri Silvestri. According to current larger foraminiferal biozonal schemes, the age of these local biozones corresponds to the Bartonian p.p. Moreover, the comparison with biostratigraphic schemes established for the Dauphinois Domain and for the Tethyan area evidences that several typical nummulitid species of the late Bartonian are lacking in the southern Dauphinois Domain, probably due to a paleogeographic control.