HYDROGEOLOGICAL SKETCH of the PELIGNA VALLEY Recent Fluvial Deposits (Holocene)
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/235958853 Hydrogeological mapping of the highly anthropogenically influenced Peligna Valley intramontane basin (Central Italy) Article in Journal of Maps · June 2012 DOI: 10.1080/17445647.2012.680778 CITATIONS READS 21 95 4 authors, including: Desiderio G. Torquato Nanni Università degli Studi G. d'Annunzio Chieti e Pescara Università Politecnica delle Marche 26 PUBLICATIONS 231 CITATIONS 100 PUBLICATIONS 636 CITATIONS SEE PROFILE SEE PROFILE Sergio Rusi Università degli Studi G. d'Annunzio Chieti e Pescara 154 PUBLICATIONS 843 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Hydrogeological map View project Hydrogeology View project All content following this page was uploaded by Torquato Nanni on 12 November 2018. The user has requested enhancement of the downloaded file. 1 2 2 1 G. DESIDERIO , C. FOLCHI VICI D'ARCEVIA , T. NANNI , S. RUSI GEOLOGICAL SCHEME (SCALE 1:100,000) From Miccadei et al., 1998, modified) Eluvial and colluvial deposits (Holocene) 21 D HYDROGEOLOGICAL SKETCH OF THE PELIGNA VALLEY Recent fluvial deposits (Holocene) D INTRAMONTANE BASIN (CENTRAL ITALY) 6 Detritic deposits (Tirrenian - Present) E Travertine (Tirrenian) SCALE 1:25,000 9 1: Dipartimento di Geotecnologie per l'Ambiente e il Territorio, Università G. D'annunzio Chieti-Pescara. 2 2: Dipartimento di Scienze e Ingegneria della Materia, dell'Ambiente ed Urbanistica, Università Politecnica delle Marche - Ancona. 3 Fluvial deposits of the "Low Sulmona terrace" (Tirrenian) Fluvial deposits of the "Upper Sulmona terrace" (Sicilian-Tirrenian) 8 C SPRING HYDROGRAPHS 2 9 Lacustrin and marshy deposits (Sicilian) 4 3 5 7 - Noce della Corte dec. 1999/may. 2001 16 - Acqua Chiara jan. 2000/may. 2001 18 - Badia apr. 2000/may. 2001 Hydrogeological Complexes Aquifers E 3 ALLUVIAL FAN HYDROGEOLOGICAL COMPLEX Recent alluvial aquifer Alluvial fan deposits (Calabrian-Holocene) This complex is constituted by the alluvial fans that are This aquifer is constituted of recent alluvial deposits and is underlain by the lacustrine and marshy A 1 hydrogeological complex. The thickness varies between 10 and 25 m and it is a single level aquifer. located at the base of the limestone mountains that border The morphology of the water table is strongly influenced by the hydraulic connections between A3 the Peligna Basin. These alluvial fans are more extensive to the aquifer and the superficial runoff drainage network and by the paleo-river beds. The depth to 9 Limestones (Mesozoic-Cenozoic) 22 the west at the base of Mt. Morrone and to the south near the water table varies from 10 m to just below 1 m. The hydraulic gradient varies from 12‰ to 2‰ D Introdacqua. The alluvial fans originating from Mt. Prezza while average water levels vary approximately by 0.9 m. The highest water levels are recorded in 9 have a smaller area, at least at outcrop. The entire complex spring while the lowest water levels are recorded in summer. The electrical conductivity (20 °C) 2 9 has an area of 50 Km and is characterised by extremely varies between 400 and 700 mS/cm while temperature trends follow those of the ambient air. The Alluvial fan heterometric and heterogeneous deposits that are mainly groundwater has a bicarbonate-calcium hydrochemistry. Recharge to the aquifer is from the major A C streams and rivers and to a lesser degree from rainfall, from infiltration due to irrigation and from limestone, breccias and gravels with a sandy-silty matrix and 2 with silty levels. Thicknesses at outcrop vary between 10 and anthropogenic discharges. Thrusts 100 m. The complex is extremely permeable due to primary 23 Eastern Aquifer porosity and hosts a single level aquifer. Multi-level aquifers 2 Blind thrusts and perched aquifers are locally present due to silty levels This aquifer occupies an area of approximately 35 Km and is constituted of the alluvial and river terrace (Terrazza Alta di Sulmona) hydrogeological complexes. This aquifer, which is a single level 2 25 and due to wedging with the lacustrine deposits of the basin. 2 aquifer, is underlain by silty lacustrine and marshy deposits. The hydraulic conductivity is between 3 4 The alluvial fan aquifers could be in hydraulic connection -4 -4 -2 -2 2 Faults 8 10 to 6 10 m/s while transmissivities vary between 1 10 e 3 10 m /s. The main discharge of with the limestone aquifers adjacent to the Peligna Basin, the aquifer is towards the springs of the River Velletta and toward diffuse issues that are located at especially where the alluvial fans a thick. The latter are also in lithological contact between the silty lacustrine and alluvial deposits. The hydraulic gradient is 25‰ Presumed faults hydraulic connection with the river terrace aquifer identified in the southern areas and 8‰ towards the north. Depth to the water table is between 5 and 40 m. by the “Terrazza Alta di Sulmona” complex. Artesian flowing Changes in water levels are approximately 0.9 m with maximum depths to the water table Rivers wells are located in the urban areas of Roccacasale, occurring during the spring or the late summer months. The main spring (Badia) has a variable Bagnaturo, Sulmona and Vittorito. These wells intercept discharge ranging between 15 and 30 l/s. Springs with smaller discharge rates, both with perennial confined aquifers connected with the more permeable and seasonal discharge regimes, are found at the boundaries with the alluvial fans. These springs deposits of the complex of the lacustrine and marshy are used for irrigational purposes. Discharge rates vary from 0.2 l/s (F.te La Torre e F.te di Salle) to 3 precipitation (mm)* discharge (l/s) conductivity (mS/cm) temperature (°C) deposits. l/s (F.te San Giovanni) with maximum rates occurring in spring and in the autumn. Electrical conductivity (20°C) varies between 200 and 800 mS/cm while temperature trends closely follow those of the seasonal ambient air temperatures. The groundwater has a bicarbonate-calcium * Raiano pluviometer for n. 7, Bagnaturo pluviometer for nn. 16 and 18 "TERRAZZA ALTA DI SULMONA" ALLUVIAL COMPLEX ++, ++ - — hydrochemistry with occasional high concentrations of Ca Mg , NO e SO partially due to This complex outcrops in the western part of the Peligna 3 4 B Basin between the towns of Raiano, Prezza, Pratola Peligna the presence of clayey, sometimes peaty deposits at the base of the aquifer, other times due to contamination from agricultural activities. Recharge is mainly from rainfall although in the summer PIPER DIAGRAM TABLE OF SPRINGS AND INCREASES/DECREASES IN RIVERBED and Corfinio and in the eastern part of the basin between the period irrigation has a role in the recharge to the aquifer. Legend towns of Pacentro and Bagnaturo. Outcrops of this complex Type N. Name Elev. (m a.s.l.) Q (aver., l/s) c (aver., mS/cm) T (aver., °C) Eastern and central western aquifer can also be identified in correspondence of the towns of Central-Western Aquifer Vittorito and Sulmona and in some areas at the edge of the 2 Recent alluvial aquifer Fonte S. Giovanni This aquifer occupies approximately 30 Km and is constituted of the alluvial fan and river terrace S5 D Introdacqua alluvial fan. The total area of the complex is (Terrazza Alta di Sulmona) hydrogeological complexes. It is underlain by silty lacustrine and marshy La Fontuccia 2 3 -4 -5 Lacustrine marshy aquifer almost 50 km . It is constituted of very heterometric deposits deposits. The hydraulic conductivity is between 4 10 to 6 10 m/s while transmissivities vary Fonte di Salle -3 -4 2 Acqua Chiara spring that range from gravels to conglomerates within a sandy-silty between 2 10 e 2 10 m /s. The alluvial deposits are wedged into the central-western terrace 1 Montesilvano matrix which is alternated with sitly-sand and silt/clay lenses deposits and the underlying silty lacustrine deposits. Thicknesses of the outcrops are approximately Springs for surficial limestone aquifers La Torre of varying thicknesses and areal extent. Levels of clay, peat 10 m. The main discharge route is from west towards the edges of the terrace. A groundwater Mineralized springs from limestone aquifers s divide can be identified within the aquifer which divides it into two separate zones. These two g Vaccanica and volcanic deposits are frequent. The thickness varies and n A2 i zones discharge one along the Rio stream in the south and the other at the series of springs that are r Noce della Corte is approximately 10 m at Bagnaturo, 10-20 m at Pratola p located along the line connecting Raiano to Corfinio. The hydraulic gradient varies from 8‰ to s Lavatorio Galli - Zugaro Peligna, 50-60 m near Raiano and 10-30 m near Prezza. The 28‰. The depth to the water table is between 10 and 30 m. Changes in water levels are on average x hydrogeological complex is extremely permeable and e Lavatorio Corfinio l 1.7 m with minimum water levels occurring in the summer-autumn period. The aquifer is in p connected to primary porosity. It hosts a single level aquifer Costa della Fonte geometrical continuity with the limestone relief of Mt. Prezza although there is no continuity with m that can occasionally be multi-level due to the presence of o S. Ippolito the main aquifer of this structure. In fact, the basal springs of Mt. Prezza which are at the lowest c deposits that have a lower permeability. The hydraulic l elevation (Raiano Group of Spring at 280 m asl) are approximately 30-40 m lower that the lacustrine a Vicenna1 i properties are similar to those of the Alluvial Fan impermeable limit of the Central-Western Aquifer.