Resumen de Hemipelagites, hemiturbidites or muddy contourites? The contribute of magnetic fabric analysis to discriminate depositional mechanisms in fine-grained sediments (Marnoso Arenacea Fm., Miocene, northern Italy)

Eleonora Dall'Olio, Fabrizio Felletti, Giovanni Muttoni

• Anisotropy of the Magnetic Susceptibility (AMS) has been used for discriminating different deep-water sedimentation processes (i.e. turbidite current, bottom-current, hemipelagic settling) in fine-grained sediments.This study suggests that fine-grained ‘non-turbiditic’ deposits of the Marnoso-Arenacea Fm. (hemipelagites afterRicci Lucchi and Valmori, 1980) cannot be explained considering simply hemipelagic settling of deep-sea mud. Weinfer that such beds were essentially deposited from stationary NW-SE bottom currents, parallel to the main basin-axis, although a continuum may exist between dilute hemipelagic settling, turbidity flows and bottom currents.