Volcanic facies associations in a modern volcaniclastic apron (Lipari and Vulcano offshore, Aeolian Island Arc)

Multibeam bathymetric and reflectivity data, high-resolution sidescan sonar mapping and ROV images have allowed reconstruction of the present-day faci es distribution within the volcaniclastic apron offshore from Lipari and Vu lcano. Primary volcanic, resedimented volcaniclastic and volcanogenic sedim entary facies have been distinguished. Primary volcanic facies are volumetr ically subordinate but play a major role in controlling the distribution of the other facies and the development of the main submarine canyons, and as the source of volcanic detritus in resedimented volcaniclastic facies. Ero sion and transport prevail in the canyons. Conversely, deposition of volcan ogenic sediments, in response to flow spreading and gradient reduction, occ urs at the canyon mouths. The influence of the adjacent islands on the offs hore processes is particularly evident in the area facing the active sector of Vulcano Island. Here, large volumes of volcanogenic sediment from the e mergent volcanic edifice are transferred downslope by subaqueous gravity fl ows allowing the construction of a volcaniclastic fan.