Caratteristiche sedimentologiche e stratigrafiche dei giacimenti sabbiosi in Mare Adriatico Settentrionale utilizzabili per il ripascimento costiero

Abstract Results of geophysical and sampling surveys carried on by ARPA RER and ISMAR CNR-Bologna offshore the Emilia-Romagna coast in 2000 are described in order to identify the potential borrow sites on the shelf and calculate the total available sand volume. Some consistent sand deposits were used in 2002 and 2007 to renourish Emilia-Romagna beaches naturally prone to intense erosion. This research focused on four sand deposits (named A, B, C1 e C2), previously identified in the Northern Adriatic shelf between 45 and 55 km off shore. Stratigraphy and sedimentology of the sand bodies identified were charachetised with 40 vibracores and 360 km of ChirpSonar Sub Bottom Profiler. Elongated transgressive sand ridges are evident in areas A, C1 and C2 while in area B sand deposit is capped by recent mud with little evidences in bathymetry. The four sand remnant deposits left from erosion of large trangressive coastal sand ridges, are caracterised by sorted fine sand overlaid with a coarser ravinement unit with erosional base. The total amount of sand was estimated in 78 million of cubic metres. C1 area was chosen as borrow site for renourisment activities in 2002 and 2007, while area A was selected only for the 2007 dredge operation.