Hydrogeological map of the Southern mountainous portion of Marche Region (Central Italy)

Abstract

Hydrogeological mapping represents an essential tool for groundwater resources management and to study regional-scale variations induced by anthropic pressure, climate change, and catastrophic natural events. The mountainous aquifers, in particular, represent the natural water towers of our planet. The Water Framework Directive 2000/60/EC establishes the action of water policy for the European Community. According to that, many water protection and management plans have been developed by the local authorities aiming at achieving the quali-quantitative targets for the protection of water resources and water bodies, ensuring a long-term sustainable water supply. The authority’s decisions are supported by hydrogeologists, with maps focusing on the main hydrogeological complexes of the national and local territories. For these purposes, a new regional-scale hydrogeological map has been realized regarding the southernmost mountainous part of the Marche Region, considering both the fractured carbonate reliefs of Sibillini Mts. and the “Laga” geological formation. This map extends from the upper portion of the Chienti river basin to the Tronto river basin and integrates both the discharge measurements conducted during the years and the information from different kind of maps, i.e. the official geological maps of Marche Region and other published maps (Pierantoni et al., 2013; Viaroli et al., 2021). The major tectonic lineaments have been interpreted from a hydrogeological point of view and reported on the map. Based on detailed geo-structural fieldwork performed in the area and on the available literature, the geological formations have been reclassified into homogeneous hydrogeological complexes. Operating in a GIS environment, they have been merged to obtain hydrogeological complexes. The boundaries of these complexes lying below the Quaternary deposits have been inferred. The main punctual and linear springs of the area have been included in the map. Spring discharge has been measured using both hydrometric current meters and artificial tracers and they have been added to the discharge data provided by drinking water companies of the area. The new map can be used as a visual decision support tool to evaluate water resources in these highly productive but relatively unexplored areas and will provide an updated database on water resources availability to the Marche Region and other public authorities.