Multi-proxy analysis in defining sedimentary processes in very recent prodelta deposits: Northern Phlegraean ofshore example (Eastern Tyrrhenian Margin)

Abstract A multi-proxy analysis of Volturno Riverprodelta deposits in the outer shelf of Northern Phlegraeanmargin (Eastern Tyrrhenian Sea) has been carried out toreconstruct the sedimentary processes acting during recenttimes. The late Holocene sediments were characterizedthrough Subbottom Chirp profiles coupled with sedimentologicaland petrophysical data. The chronostratigraphicframework was achieved by means of colorimetricparameter a* correlations with nearby dated marine sediment.A time interpretation of about 2,300 years BP isestimated for the sedimentary record collected in thecores. Seismic stratigraphic analysis shows late Holoceneouter shelf deposits, characterized by fluid escape featuresand small-offset faults. However, the undisturbed sedimentationand the preservation of an internal geometry atdecimetre scale, as detected by the sedimentological andpetrophysical analysis, indicates a slow sliding withoutsediment reworking for this sedimentological body. So fara possible recent (\2,300 years BP) shear dominateddownward displacement of high water content sediments,triggered by the occurrence of seismic activity, is inferred.Based on the depth-age conversion of the detected lithologicalfeatures, a regular climatically driven change inthe sediment supply of the prodelta depositional environmentis suggested. The detection of spectrophotometrycorrelations of Holocene shelf margin sediments, severalkm apart, goes beyond the previous work and confirmseven for continental shelf area the potential value ofspectrophotometer data in high-resolution stratigraphiccorrelations.