New Gravimetrical Map of The Rieti Intra-Mountain Basin (Central Apennines, Italy)

Abstract

This paper describes the acquisition of the gravity data and their analysis to model and map the bedrock configuration of the Rieti Basin (hereafter RB); a typical intra-mountain tectonic depression of Central Apennines in Italy, related to a still active tectonic extensional regime. The study involved a test area of 35 km2 occupied by 110 gravity stations. The new gravity measurements were merged with the gravity data of the 358 gravity stations collected during the 1995 gravity survey (Ciccollella et al., 1995). The gravity data resulted from the network adjustment were used to calculate the Bouguer anomaly map. To realize the 2-D gravimetric models of the RB, a realistic density of 2,15 g/cm3 for the unconsolidated Quaternary deposits, a density of 2.50 g/cm3 for the Travertine and a density of 2.60 g/cm3 for the Meso-Cenozoic pelagic basin deposits were used (Skrame, 2011). The models obtained matched quite well with the exiting geological and geophysical data. The new bedrock surface topography map of RB provides a new more detailed and representative image of the buried morphology, and gives a more accurate evaluation of the thickness of the Plio-Quaternary sedimentary infilling.