The Barcellona Pozzo di Gotto Basin of northeastern Sicily, central Mediterranean, is a Plio-Pleistocene peri-Tyrrhenian shelf embayment that formed by the collapse and marine inundation of bedrock fault-blocks in response to regional tectonic extension. The study focuses on the well-developed transgressive systems tract of the lower bay-fill sequence. This succession of middle Pliocene to Lower Pleistocene marine deposits has a mixed siliciclastic to bioclastic composition and is ~73 m thick in mid-bay outcrop section. The deposits are sandy to silty facies indicating a wavedominated bay rich in suspended sediment and influenced by storms and tidal currents. Facies associations represent upper and lower shoreface, offshore-transition and mid-bay offshore zones. The abundance of silty to sandy suspension is attributed to the entrapment of fine sediment entrained by storms and tides and possibly derived from nearby streams. The supply of sediment from the bay's shoreline zone probably combined with fine-grained sediment drift from offshore areas, as is also suggested by admixtures of outer circalittoral benthic microfauna. Facies-based estimates indicate a water depth of ≤ 25 m for the mid-bay area, with a mean depth of ~10 m for fairweather wave base and ~15-16 m for storm wave base. The shallow bay hosted circalittoral benthic fauna typical of deeper water Mediterranean shelves, which can be attributed to the high turbidity of the bay water (limited light penetration).The stratigraphic organization of the facies associations and their fauna assemblages reveals that the succession consists of six parasequences, or transgressive-regressive cycles, bounded by marine flooding surfaces and showing an overall deepening upward trend. The parasequences are 4-17 m thick, and some include well-developed transgressive deposits and also a relatively thick mid-cycle condensation zone. The latter indicates a prolonged balance between the rates of accommodation development and its filling by slow aggradation. Palaeoecological and taphonomic criteria defining a condensation maximum allow the maximum flooding surface to be identified, typically in the upper part of the mid-cycle condensation zone. The parasequences have time spans of ~300 kyr and correlate with the 4th-order regional sequences recognized in the central Mediterranean. Accordingly, they are inferred to be the local equivalents of these high-frequency sequences, owing their facies architecture to a relatively high rate of tectonic subsidence in the peri-Tyrrhenian coastal region of northern Sicily. These would thus be type 2 sequences involving little or no fall in relative sea level and hence developed as parasequences. The integration of sedimentological, biostratigraphic, palaeoecological and taphonomic data proves to be a powerful method for high-resolution sequence stratigraphy and palaeoenvironment reconstruction, including sediment dynamics, palaeogeography and bathymetric changes.

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