Lithological and hydrogeological setting

The region of Campania in the southern part of the Italian peninsula has an area of about 13 500 km2, and a coastline along the Tyrrhenian Sea. The landscape is dominated inland by the Apennine mountain ranges reaching altitudes of 1000-2000 m, accounting for 32% of the land area. Coastal plains account for a further 18%, while the rest of

From: Dragoni, W. & Sukhija, B. S. (eds) Climate Change and Groundwater. Geological Society, London, Special Publications, 288, 25-38.

DOI: 10.1144/SP288.3 0305-8719/08/$15.00 © The Geological Society of London 2008.

the region consists of low-altitude hills and valleys. Geologically speaking, Campania consists of three coastal plains (of the rivers Garigliano, Volturno and Sele) filled by alluvial and pyroclas-tic deposits, of the Roccamonfina and Vesuvius volcanoes, pyroclastic hills in the Phlegrean Fields, and carbonate Mesozoic mountains surrounded by impervious arenaceous-clayey-marly sediments (Fig. 1) (Budetta et al. 1994; Celico et al. 2004a).

In the alluvial-pyroclastic plains, permeability is medium-high, chiefly depending on the sediment grain size. In the Volturno river plain, the main aquifer, confined or semiconfined, is located in the hydrogeological units (with sand and gravel grain size) located below the Campanian ignimbrite tuff. The aquifer is also recharged from the Meso-zoic limestone mountains. Shallow aquifers have also been recognized in the coastal sector, along the course of the Volturno river, and in the southeastern sector.

Nitrate, manganese and iron are the most common groundwater contaminants in the area. Iron and manganese occur naturally, but high nitrate levels indicate severe contamination from human activities (application of nitrogen fertilizers and wastewater disposal).

In the southern part of the region, the Sele river plain contains a multilayered coastal plain aquifer (thickness > 200 m) covered by 50 m of silty-clayey deposits. In the hills of the Phlegrean Fields and the volcanoes of Roccamonfina and Vesuvius the piezometric surface indicates a radial groundwater flow chiefly towards the aquifers of the adjacent plains. The Vesuvius (and the old Somma volcano) aquifer consists of lavas, scoria and pyroclastics: the groundwater body is prevalently unconfined and very deep below the soil surface. The main aquifers are found in the carbonate massifs, which have a very high permeability due to a well developed karstic network. The groundwater bodies reach the springs with copious

Fig. 1. Lithological map of Campania.

discharge (in some cases more than 1 m3/s), located at the foot of the mountains, and feed the adjacent plains. The total spring discharge of Campania is about 70 m3/s.

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