An integrated approach to investigate bio-concretionned rocky outcrops (Tegnùe) of the Marine protected Area offshore Chioggia, northern Adriatic shelf.

BERGAMASCO A.; DONNICI S.; CAROL E.; BARADELLO L.; Y OTROS

Ustica

Congreso; GeoSub 2016; 2016

In the north-western Adriatic Sea the silicoclastic inner shelf is interrupted by localized rocky outcrops, a subtype of coralligenous habitat, up to 2-3 m high. Such ?rocks?, grouped under the dialectal name of tegnùe, are known by fishermen for their fishing value but also as a threat to trawling. They are basically carbonate cemented sands with a strong biogenic overprint that contributes to the final construction of the ?reef? (Donnici et al., 2015). Many genetic interpretations have been proposed so far, among other the cementation due to beach-rock like processes or the action of ascending fluids enriched in hydrocarbons.In this work we show the results of a project aimed at characterizing the tegnùe field located in the Marine Protected Area offshore Chioggia (ZTB), Venice, by underwater and geophysical surveys, and laboratory analysis. In particular, we focus on the considerable effort made by SCUBA divers, which was essential to get accurate information and carry out hydrological measurements and samplings.