Late Quaternary Geology and morphoevolution of the Volturno Coastal Plain, Southern Italy

The Volturno alluvial-coastal plain is a relevant feature of the Tyrrhenian side of southern Italy. Its plan-view squared shape is due to Pliocene-Quaternary block-faulting of the western flank of the chain. The Quaternary infill of the Volturno plain has been here studied by means of well data. An asymmetrical shape of its ancient morphology - with a steeper slope toward the north-west border - and the lack of coincidence between the present course of the Volturno River and the main buried bedrock incision are significant achievements of this study. Landforms analysis completed the frame of the recent evolution of the plain

Multidisciplinary approach for fault detection: Integration of PS-InSAR, geomorphological, stratigraphic and structural data in the Venafro intermontane basin (Central-Southern Apennines, Italy)

A multidisciplinary methodology, integrating stratigraphic, geomorphological and structural data, combined with GIS-aided analysis and PS-InSAR interferometric data, was applied to characterize the relationships between ground deformations and the stratigraphic and the morphostructural setting of the Venafro intermontane basin. This basin is a morphostructural depression related to NW-SE and NE-SW oriented high angle normal faults bordering and crossing it. In particular, a well-known active fault crossing the plain is the Aquae Juliae Fault, whose recent activity is evidenced by archeoseismological data. The approach applied here reveals new evidence of possible faulting, acting during the Lower to Upper Pleistocene, which has driven the morphotectonic and the environmental evolution of the basin. In particular, the tectonic setting emerging from this study highlights the influence of the NW-SE oriented extensional phase during the late Lower Pleistocene – early Middle Pleistocene, in the generation of NE-SW trending, SE dipping, high-angle faults and NW-SE trending, high-angle transtensive faults. This phase has been followed by a NE-SW extensional one, responsible for the formation of NW-SE trending, both NW and SE dipping, high-angle normal faults, and the reactivation of the oldest NE-SW oriented structures. These NW-SE trending normal faults include the Aquae Juliae Fault and a new one, unknown until now, crossing the plain between the Venafro village and the Colle Cupone Mt. (hereinafter named the Venafro-Colle Cupone Fault, VCCF). This fault has controlled deposition of the youngest sedimentary units (late Middle Pleistocene to late Upper Pleistocene) suggesting its recent activity and it is well constrained by PS-InSAR data, as testified by the increase of the subsidence rate in the hanging wall block

La valutazione delle deformazioni del suolo nella piana di Venafro mediante l’elaborazione di dati PSInSar, morfo-strutturali e stratigrafici

I bacini intramontani dell’Appennino centro-meridionale sono soggetti, sin dalla loro genesi (Pleistocene inferiore), a deformazioni del suolo, la cui non uniforme distribuzione e la cui diversa entità sono una risposta all’attività di faglie, intersecanti e bordanti le pianure, e al costipamento differenziale dei depositi costituenti le successioni sedimentarie di riempimento. Al fine di valutare la distribuzione spaziale dei movimenti verticali e le relative velocità, e di interpretarne correttamente le cause, è stato affrontato uno studio multidisciplinare che ha previsto l’elaborazione di dati radar con tecnica PSInSAR, lo studio geomorfologico e strutturale e l’analisi stratigrafica di dati di sottosuolo della piana di Venafro, ampia depressione tettonica interposta tra i M. delle Mainarde-M. di Venafro ed i M. del Matese e drenata dal F. Volturno. L’interpolazione dei dati PS, effettuata in ambiente GIS, riferita a due intervalli di tempo, 1995–2000 (ERS) e 2003–2008 (ENVISAT) ha permesso di valutare i ‘cumulative vertical displacements’ (mm), i ‘displacement rates’ (mm/a) e il ‘gradient field’ dei ‘displacement rates’, consentendo di individuare alcuni settori del bacino che si distinguono per tassi di subsidenza superiori alla media e per comportamento deformativo costante nel tempo. Risulta evidente una correlazione tra la distribuzione spaziale del quadro deformativo di natura interferometrica, lo sviluppo geometrico delle faglie che interessano la piana e la natura litologica del riempimento sedimentario. I valori maggiori di subsidenza si registrano nel settore centrale della piana, probabilmente indotti da un maggiore spessore dei depositi di riempimento, nonché dalla presenza di depositi argillo-sabbiosi poco addensati e più suscettibili al costipamento, così come dalla presenza di alcuni lineamenti tettonici orientati NE-SW e NW-SE. In particolare, i valori maggiori si registrano a valle di una scarpata morfologica, orientata NW-SE, coincidente anche con un importante ‘knick point’ del F. Volturno, oltre che a valle di una faglia, orientata NW-SE (Faglia dell’’Aquae Juliae’), attiva in tempi storici per aver dislocato l’acquedotto romano.PublishedFirenze2T. Tettonica attiva5IT. Osservazioni satellitariope

Coastal inundation risk assessment due to subsidence and sea level rise in a Mediterranean alluvial plain (Volturno coastal plain - southern Italy)

Interdisciplinary studies of the last years highlight that the Italian coasts are significantly subject to retreat and to inundation by sea ingression due to natural and anthropic causes. In this study, the effects of future relative sea level have been evaluated for the Volturno River Plain, one of the widest coastal plain in southern Italy. The plain is characterized by high economical and ecological value, for the presence of farm activities, tourist structures and wetland protected zones. The study area is potentially prone to coastal flooding due to its very low topography and because it is affected by a severe subsidence, which emphasize the local effect of sea level rise due to the ongoing climate changes.In accordance with the guidelines of the MEDFLOOD project, the areas prone to inundation in the years 2065 and 2100 have been evaluated by comparing the future topographical information and expected relative sea level scenarios. The local Vertical Ground Displacements have been derived by PS-InSAR processing data whilst the mean values of the scenarios RCP 2.6 and RCP 8.5 provided by the IPCC (2014) have been used as future sea level projections in 2065 and 2100. The PS-InSar data elaboration shows that the area affected by subsidence corresponds to 35% of the Volturno plain and that the annual rate of the phenomenon ranges between -1 and -25 mm/yr.The inundation analysis, based on the classification of the areas in four hazard classes, indicates that in 2065 the zones located below the sea level will increase approximately of 50% respect to the present conditions, while between 2065 and 2100 the increase can be at least of 60% (IPCC, RCP 8.5 scenarios). Considering the socio-economical and ecological exposure, evaluated following the EUROSION project guidelines, the coastal flooding risk maps have been produced. Almost 8.2 km2 and 14.4 km2 of the investigated area has to be considered subject to very high marine inundation risk in 2065 and 2100, respectively