River terraces in the Fiume Tronto drainage basin: a contribution to morphotectonic investigations

The aim of this work is to provide a methodological input based on geostatis tical topograp hic analyses for the detection of morphological .anoma lies induced by neotectonic activity on fluvial terrace surfaces. The study area corresponds to the distal portion of the Fiume Tro nto dra inage basin (Southern Marc he region of Central It aly); the basin developed on Plio-Pleistoce ne marine terrigenous deposits and its arrangement was strongly influenced by Quaternary uplift and regional WSW-ENE and E-W trend ing fault zones. Detailed surveys allowed to verify the location of surfaces, at several levels; they are the remnant s of Quaternary fluvial terraces, formed in respo nse to both climatic oscillations and regional uplift. Several points at the top of the surfaces were samp led by GPS and then geostatistically processed (Kriging method) to provide an unbiased interpretation of the chronological seque nce of terraces . The geometrical setting of the terraces seems strongly influenced by the regional uplift and by the activity of the Tr onto major fault. Results of geostatistical analysis, comp ared to the DTM indic ated that minor Qu atern ary faults dislocated the terraces. This is in agreement with the out comes of previous works, thu s confirming the usefulness of this methodological approach in the study of fluvial terraces as neotectonic indicators.