In central Italy several intermountain basins (half-grabens) are the result of an extensional tectonic phase (upper Pliocene to present) that breaks the mountain chains length with NW-SE direction. In Umbria, the Tiberino basin is the widest one, crossing from north to south the entire region and splitting near Perugia in two branches, the western ending in the Terni basin, the eastern, named Umbra Valley, that is the goal of this paper. The river network is a useful marker in order to evaluate the local tectonic tilting (longitudinal and lateral). The river response is evident both in longitudinal profile and in channel pattern adjustment. The quantitative geomorphology investigates the linkage between processes, landforms and tectonic effects on topography. Actually new topographic data from remote sensing are available according to powerful calculation methods in order to investigate the river network trend in neotectonic areas. The traditional methods (field work and aerial photograph investigations) are enhanced from Digital Elevation Model and remote sensing data processing. New techniques allow the computation of original geomorphic values setting up the possibility to compare the activity of the tectonic degree. The paper is a preliminary report to an integrated approach for the knowledge of geomorphologic evidences of neotectonic in the study area.
Relazione tra evoluzione idrografica e neotettonica nella Valle Umbra: analisi geomorfologica quantitativa su DEM integrata a dati di superficie.
MELELLI, Laura
2009
Abstract
In central Italy several intermountain basins (half-grabens) are the result of an extensional tectonic phase (upper Pliocene to present) that breaks the mountain chains length with NW-SE direction. In Umbria, the Tiberino basin is the widest one, crossing from north to south the entire region and splitting near Perugia in two branches, the western ending in the Terni basin, the eastern, named Umbra Valley, that is the goal of this paper. The river network is a useful marker in order to evaluate the local tectonic tilting (longitudinal and lateral). The river response is evident both in longitudinal profile and in channel pattern adjustment. The quantitative geomorphology investigates the linkage between processes, landforms and tectonic effects on topography. Actually new topographic data from remote sensing are available according to powerful calculation methods in order to investigate the river network trend in neotectonic areas. The traditional methods (field work and aerial photograph investigations) are enhanced from Digital Elevation Model and remote sensing data processing. New techniques allow the computation of original geomorphic values setting up the possibility to compare the activity of the tectonic degree. The paper is a preliminary report to an integrated approach for the knowledge of geomorphologic evidences of neotectonic in the study area.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
