Multi-proxy signatures in deep-water fine-grained sediments: Inherited versus syn-sedimentary factors controlling sediment compositions within a foredeep basin (Paleogene Adriatic foredeep – Northern Italy)

Abstract

This work explores the significance of sedimentary proxies recorded within the Paleogene fine-grained detritus of the Adriatic foredeep (Northern Italy). Such sequences represent the only sedimentary record describing the source-to-sink system delivering detritus from the growing Alpine belt to the basin during the Eocene - Oligocene boundary. The combination of x-ray powder diffractometric, petrographic, SEM-EDS and biostratigraphic analyses on more than twenty samples from the Ternate-Travedona Formation, the Chiasso Formation, and the Villa Olmo Conglomerate allowed to identify the source areas of detritus and potential fluvial paleo-drainages, possibly ascribable to two different sectors of the Southalpine domain. Comparison between these results and the petrographic composition of the Cretaceous wedge in the same area opens to the possibility that Cenozoic drainages were inherited from more limited paleo-drainages developed during the end of the Mesozoic. Results of provenance analysis also gives new insights on how detrital compositions may vary in function of grain-size in tropical-subtropical environments.