GNGTS 2014 - Atti del 33° Convegno Nazionale

GNGTS 2014 S essione 3.2 151 Fig. 1 – Gravity anomaly Bouguer map for central Italy, showing the data set we used for this study and the traces of the three studied sector. g/cm 3 . The close spacing of stations and the wideness of the covered area give us the chance to use the gravimetric data to obtain information on both the deep and the shallow geological structures. From these randomly distributed data we generated a Bouguer gravity map of central Italy, using Minimum Curvature interpolation method, with a grid cell size of 1 km. The map shows two different gravity anomaly signals that characterize Tyrrhenian and Adriatic Domains, which show long-wavelenght positive (+70 mGal) and negative (-70 mGal) Bouguer gravity anomalies respectively, separated by a sharp arc-shaped step below the transition zone. In the Tyrrhenian Domain short-wavelenght relative minima are also observed, related to syn-tectonic basins (Radicofani Basin, Val di Chiana Basin, Tiber Basin) and volcanic complexes (M. Amiata, Roman volcanic district). By contrast, in the Adriatic Domain two wide gravity minima can be observed, NW-SE trending, separated by a relative maximum, corresponding to the Conero area. These anomalies are related to Po Plain-Adriatic foredeep (Royden and Karner, 1984), but also to the stacking of slices of continental crust beneath the adjacent mountain ridge. These general features were already well represented in the ISPRA (2006) map. For this first experiment we considered a regional transect, consisting of three WSW-ENE trending sections, radiating from the M. Amiata area towards the Adriatic coast (Fig. 1). The Northernmost section reaches the coast at Pesaro; the intermediate few km north of Ancona; and the third approximately at Civitanova. Along these traces, a large amount of data, mainly acquired for industrial purposes (oil and geothermal exploration) is available, constraining both the surface