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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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A short Lower Pleistocene section, cropping out in SE Sicily, is studied. The sequence mainly consists of richly fossiliferous sandy layers with Arctica islandica, deposited in mid-shelf environments. Molluscs, bryozoans, serpuloideans and calcareous algae are investigated, to identify species with palaeoclimatological implications.

We studied the sclerobiont community associated with organogenic and lithic cobbles from soft bottoms in the Khao Lak coastal area (Andaman Sea) that was damaged by the 2004 tsunami. The 15 cobbles examined originate from grab and hand sampling carried out in the years 2006 and 2007 in the depth range of 4.6-15.2 m. A rich endo-and epibenthos was identiWed, mainly consisting of algae, foraminifers, sponges, cnidarians, polychaetes, bryozoans and bivalves. Associations on each examined cobble show similarities in composition and structure being characterized by a few dominant groups. DiVerences were noted in the degree and pattern of colonization, distinguishing for each cobble an upward and a downward side at the time of sampling. The mean total coverage is 15.09% being higher on the upper sides (17.4%) compared to the lower sides (12.8%). Calcareous algae, bivalves and sponges prevail on upper sides, while bryozoans prevail on lower sides. The sclerobionts distribution allowed to infer the orientation of cobbles on the seaXoor during colonization.Major colonization values, exceeding 30% coverage, were observed on organogenic cobbles located in the proximity of reefs or collected from below 12 m of water depth. Conversely, cobbles from the shallowest stations result poorly colonized, independently of their composition. The water turbidity and wave motion as a possible cause of the observed distributions were discussed. The Khao Lak cobble community seems to be largely unaVected by the tsunami event, as suggested by the estimated biodiversity, abundance and coverage of sclerobionts.