Stratigraphic and structural evolution of Naples harbour over the last 12 Ka

The interpretation of high-resolution smic reflection profiles permitted the recognition of the main stratigraphic and tectonic events that occurred in Naples Harbour, offering new insights on the geology of this urban area. Sedimentary and volcanic units (the latter originating from the Phlegrean Fields and Vesuvius) were singled out. Volcanic products from the Phlegrean Fields cover the whole urban area. The most widespread unit is the Neapolitan Yellow Tuff (12 ka BP), on which most of the city is built. It is interlayered within a sedimentary succession characterized by marine and alluvial facies. The Vesuvius volcanics, on the other hand are present in the eastern harbour area. Both Phlegrean Fields and Vesuvius volcanic products are covered by a terrigenous succession deposited during the post-glacial sea-level rise. NE-trending normal faults offset the Neapolitan Yellow Tuff, while NW-trending normal faults offset the Vesuvius products downthrowing the south-western area. The dismantling of these fault scarps gave rise to talus wedges interlayered within the Holocene marine deposits. Sequence stratigraphic analysis allowed the identification of erosional (both subaerial and marine) and flooding surfaces. These surfaces are related to the rise and stillstand of the sea level of the last 12 ka BP sedimentary succession of Naples Harbour. This succession shows an early back shifting (onlap) deposits (up to the maximum flooding surface), followed by a depositional regression (prograding deltaic facies) during the present highstand.