Morphometry and debris-flow susceptibility map in mountain drainage basins of the Vallo di Diano, southern Italy

In watershed mountain basins, affected in the last decades by strong rainfall events, the role of debris-flow and debris flood processes was investigated. Morphometric parameters have proven to be useful first-approximation indicators in discriminating those processes, especially in large areas of investigation. Computation of morphometric parameters in 19 watershed mountain basins of the western side valley of the Vallo di Diano intermontane basin (southern Italy) was carried out. This procedure was integrated by a semi-automatic elaboration of the potential susceptibility to debris flows, using Flow-R modelling. This software, providing an empirical model of the preliminary susceptibility assessment at a regional scale, was applied in many countries of the world. The implementation of Flow-R modelling requires a GIS application and some thematic base maps extracted using DEMs analysis. A 5-meter-resolution DEM has been used in order to produce the susceptibility maps of the whole study area, and the results are compared and discussed with the real debris flow/flood events that occurred in 1993, 2005, 2010, and 2017 in the studied area. The results have provided a good reliability of Flow-R modelling within small catchment mountain basins

Geomorphic analysis and semi-automated landforms extraction in different natural landscapes

Increasing knowledges in the computer algorithms for calculating morphometric properties of the Earth's surface has provided in the last decades many methods of semi-automated extraction and classification of landforms. The use of digital elevation models (DEMs) and specific algorithms in GIS applications has made easier and faster the semi-automated recognition of landform classes. In this paper, we propose a new toolbox, implemented from the original version of the Jenness's landform classification, which takes into account a revision of the standard landform classes extracted by GIS. The new toolbox allowed us to extract 48 landform classes, and refined the typology of landform features in different natural landscapes, from a geomorphological point of view. The landforms classification and the morphometry of six different selected sites pertained to volcanic areas, mountain ridges, karst endorheic basins, hilly areas, fluvial sectors, and coastal plain areas were analysed and discussed. The selected areas are located in Southern Italy, where many different geological and geomorphological landscapes exist

Electrical imaging and self-potential survayes to study the geological setting of the Quaternary, slope depositsin the Agri high valley (Southern Italy)

We present the results of a geophysical survey carried out to outline the structural modelling of Quaternary slopedeposits in the northern part of the Agri high valley (Basilicata, Southern Italy). Quaternary folding and brittle deformations of the subaerial slope deposits have been studied combining electrical imaging and self-potential surveys with geological structural analysis. This integrated approach indicates that the area underwent both transpressional and transtensional tectonics during Pleistocene times as testified by the existence of a push up structure in the basement buried by deformed Quaternary breccias. On this basis, the valley appears to be a more complex structure than a simple extensional graben, as traditionally assumed in the literature

Multidisciplinary investigations on the Roman aqueduct of Grumentum (Basilicata, Southern Italy)

The Romans built the ancient town of Grumentum during the 3rd century B.C. in the southern part of the Agri
 high Valley (Basilicata Region, Southern Italy) near the confluence of the Sciaura stream in the Agri River.
 Now it is one of the most important archaeological sites of Southern Italy. In fact, after a period of wars in
 this area between Romans and Carthaginians, a great deal of restoration was started in 57 B.C. These works
 affected the city walls, public buildings and finally endowed the Roman colony with important infrastructures,
 such as the new aqueduct. In this work, we attempt to reconstruct the ancient layout of the Roman aqueduct
 of Grumentum. As a starting point, we followed some descriptions from the 19th century, when the structure
 was still well preserved. Then, we performed a multidisciplinary geophysical approach to the best preserved
 remains of the aqueduct. In particular, the geophysical investigation started with the use of a portable GPS allowing
 us to acquire the co-ordinates of the outcropping rests of the ancient structure. Then, we used an optical
 pumping magnetometer to perform seven gradiometric maps over a broad area of about 8000 m2. From
 the literature descriptions, dating to the first part of the 19th century, we can deduce that the state of preservation
 of the Roman aqueduct was much better than the present one. Thus we can hypothesise as the cause of
 its fast involution the fact that it was located in the epicentral area of the large destructive earthquake which
 occurred in the Basilicata Region in 1857 (Mallet, 1862). To this aim, we performed a first attempt to correlate
 the state of preservation of the aqueduct remains with the local seismic amplification by means of the
 HVSR (Horizontal to Vertical Spectral Ratio) technique. This survey allowed us to obtain the site amplification
 spectra along the aqueduct layout and assess the fundamental vibration frequency of the investigated
 structure. The possibility of landslides was ruled out by a careful geological survey. The relationship between
 aqueduct path and damage should then be attributed to closeness to earthquake seismogenic fault

Electrical imaging and self-potential survayes to study the geological setting of the Quaternary, slope depositsin the Agri high valley (Southern Italy)

We present the results of a geophysical survey carried out to outline the structural modelling of Quaternary slopedeposits in the northern part of the Agri high valley (Basilicata, Southern Italy). Quaternary folding and brittle deformations of the subaerial slope deposits have been studied combining electrical imaging and self-potential surveys with geological structural analysis. This integrated approach indicates that the area underwent both transpressional and transtensional tectonics during Pleistocene times as testified by the existence of a push up structure in the basement buried by deformed Quaternary breccias. On this basis, the valley appears to be a more complex structure than a simple extensional graben, as traditionally assumed in the literature

Caratteri morfoevolutivi e valutazione dei distacchi potenziali di un versante in roccia nei pressi di San Chirico Raparo (Basilicata): applicazione integrata di metodi geologici e geofisici

. Un approccio multidisciplinare basato su indagini geomorfologiche, geostrutturali e geofisiche ha permesso di valutare l’evoluzione morfodinamica e le tipologie prevalenti di instabilità di un versante in roccia ubicato nell'Appennino lucano, nei pressi dell’abitato di San Chirico Raparo. L’area di studio è rappresentata da un plateau di travertino posto a circa 810 metri s.l.m. che poggia su conglomerati quaternari appartenenti alla successione plio-pleistocenica del bacino di Sant’Arcangelo Auctt. e su un'alternanza arenaceo-pelitica oligo-miocenica ascrivibile alla Formazione di Albidona. Il litosoma di travertino è inciso trasversalmente da corsi d’acqua di basso ordine gerarchico che - in un intervallo temporale di circa 80.000-90.000 anni - hanno prodotto una parete verticale di 30 metri circa non in equilibrio con il sistema morfoclimatico attuale. Il versante in roccia evolve attualmente con meccanismi di rock fall, causando frequenti danni alle infrastrutture circostanti. Episodi di crolli sono stati registrati anche in coincidenza dell’evento sismico del Settembre 1998 con epicentro nella contigua area della Catena del Pollino. Rilievi geologici e strutturali hanno permesso di ricostruire la geometria e lo stato di fratturazione del corpo roccioso. I dati giaciturali sono stati elaborati con il metodo della sovrapposizione che ha rivelato i meccanismi di instabilità dominanti lungo la parete rocciosa e le famiglie di discontinuità cinematicamente attivabili. Gli aspetti relativi alla distribuzione ed all’andamento delle fratture in profondità e la geometria della superficie di appoggio dei travertini sono stati investigati tramite tomografie geoelettriche ad alta risoluzione, grazie alle quali è stato possibile riconoscere anche la spaziatura dei principali sistemi e dunque – unitamente alle misure sul campo - le volumetrie potenzialmente instabili. L'integrazione dei dati acquisiti con le diverse metodologie ha fornito un quadro sufficientemente chiaro sui caratteri morfoevolutivi del fronte roccioso nell'attuale contesto climatico ed in coincidenza di triggering sismico