The Pliocene deposits outcropping at Taggia and Castellaro (western Liguria) belong to a fan-delta complex built up on the Saorge-Taggia tectonic lineament. Sedimentary facies and processes form downflow a continuum: (1) slide, scree-cone and non-cohesive debris flow deposits; (2) gravelly deposits, from massive and disorganized to stratified and internally organized, produced by hyperconcentrated inertia flows; (3) gravelly-sandy and sandy deposits produced by high density turbidity currents; (4) sandy low-density turbidity current deposits; (5) decantative silty mudstones. The fan-delta complex is formed by three superimposed and coarse-grained sedimentary bodies of hectometric thickness separated by two major muddy levels of thickness up to pluri-decametric. These sedimentary bodies are distinguished as: (a) lower unit, overlaying the substratum and formed by immature, massive breccias and conglomerates; (b) intermediate unit, formed by sandy conglomerates from massive to stratified, as well as by sandstone lenses; the foreset-beds dip ranges from 30-35 degrees to 8-10 degrees downflow; (c) upper unit, similar in lithostratigraphy to the previous, but richer in sand; the foreset-beds dip ranges from 20 degrees to 5-10 degrees downflow. Proximal segments of every unit show strongly erosional basal surfaces reaching dips not beyond 10-12 degrees . Syn-sedimentary tecnonic events caused a lateral shifting of the higher units toward SW. A uni-vocal main flow direction N150 through disk-shaped imbricated pebbles and foreset-beds dip is recognized only in the upper unit. Beginning from every major mudstone level, the vertical distribution of facies presents a symmetrical trend (coarsening upward-fining upward) within each system. Therefore, the three units are identified as transgressive-regressive cycles controlled by tectonically induced relative sea level changes. As a consequence, the sedimentary evolution of the fan-delta complex is interpreted as a sequence of three superimposed sedimentary cycles, within which the breaking down and basculating continental margin caused each time a sinking of shelf and a raising of hinterland, so renewing at the same time the basinal water deep and the elevation of drainage basins.

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