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The Miocene marine molasse of Digne is thought to have been deposited in a structural embayment with a gulf‐like morphology. This gulf was closed toward the alpine front and opened on to the Rhodano‐Provençal gulf, part of the Tethys. The outcrop of Auribeau, located on the northern margin of the gulf of Digne, displays a conspicuous vertical record of different tidal cyclicities indicating the importance of tidal dynamics on the Miocene marine molasse deposits. For the first time these tidal cyclicities are analysed from a vertical section (deposited by vertical accretion) and these are similar to the cyclicities described from megaripples or sand waves (deposited by lateral accretion). By means of thickness measurements and time series analysis, four main tidal cyclicities have been recognized: (1) the diurnal cyclicity (as it exists in the Atlantic Ocean); (2) the semi‐lunar month cyclicity of neap to spring; (3) the lunar month cyclicity of neap, high spring, neap to low spring and (4) the semi‐annual cyclicity of solstice to equinox.

Tidal rhythmites can represent continuous deposition over several years at a rate of a few decimeters per year. The development of these tidal facies in certain basins remains problematic with respect to the processes responsible for the accommodation necessary for multi-year rhythmite deposition and preservation.In the Digne foreland basin, the Miocene marine infill contains abundant tidal rhythmite successions. Some of these tidal facies cropping out on the western margin of the basin are described and analyzed in detail. Thickness measurements indicate that the rhythmite successions records four orders of tidal cycles: semidiurnal, semilunar, lunar, and semiannual. Cycle continuity suggests that sedimentation was continuous over several years, with a deposition rate that remained almost constant (ഠ4 m per year). Sedimentological evidence indicating little change in water depth suggests that the accommodation necessary for deposition was created at a rate comparable to that of rhythmite accretion.Because the studied tidal rhythmite succession is traceable regionally, accommodation may have been regional in origin. Because synsedimentary tectonic activity is well established for the Digne Basin and sequence correlation indicates that the tidal rhythmites thicken into axes of en échelon synclines along the basin western margin, very rapid subsidence events of tectonic origin are assumed to be the key process that created such accommodation.

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