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The flooding susceptibility of alluvial fans in the Southern Apennines has long been neglected. To partly address this oversight, we focus on the region of Campania which contains highly urbanized piedmont areas particularly vulnerable to flooding. Our findings are based on stratigraphic analysis of the fans and morphometric analysis of the basin‐fan systems. Using geomorphological analysis we recognized active alluvial fans while stratigraphic analysis together with statistical analysis of the morphometric variables was used to classify the fans in terms of the transport process involved. The results indicate that in the geological context examined, the best discrimination between debris flow (Df) and water flood (Wf) processes is achieved by means of two related variables, one for the basin (feeder channel inclination, Cg) and one for the fan (fan length, Fl). The probability that an unclassified fan belongs to group Wf is computed by applying a logistic function in which a P value exceeding 0.5 indicates that a basin/fan system belongs to group Wf. This important result led to the classification of the entire basin/fan system data. As regards process intensity, debris flow‐dominated fans are susceptible to the occurrence of flows with high viscosity and hence subject to more severe events than water flood‐dominated fans. Bearing this in mind, the data gathered in this study allow us to detect where alluvial fan flooding might occur and give information on the different degrees of susceptibility at a regional scale. Regrettably, urban development in recent decades has failed to take the presence of such alluvial fans into account due to the long recurrence time (50–100 years) between floods. This paper outlines the distribution of such susceptibility scenarios throughout the region, thereby constituting an initial step to implementing alluvial fan flooding control and mitigation. Copyright © 2012 John Wiley & Sons, Ltd.

Abstract. This paper deals with the risk assessment to alluvial fan flooding at the piedmont zone of carbonate massifs of the southern Apennines chain (southern Italy). These areas are prime spots for urban development and are generally considered to be safer than the valley floors. As a result, villages and towns have been built on alluvial fans which, during intense storms, may be affected by flooding and/or debris flow processes.The study area is located at the foothills of the Maddalena mountains, an elongated NW-SE trending ridge which bounds to the east the wide intermontane basin of Vallo di Diano. The area comprises a wide detrital talus (bajada) made up by coalescent alluvial fans, ranging in age from the Middle Pleistocene to the Holocene. Historical analysis was carried out to ascertain the state of activity of the fans and to identify and map the zones most hit by past flooding. According to the information gathered, the Sala Consilina fans would appear prone to debris flows; in the past these processes have produced extensive damage and loss of life in the urban area. The watershed basins feeding the fans have very low response times and may produce debris flow events with high magnitudes. Taking into account the historical damage, the fan surface morphology, and the present urban development (street orientation and hydraulic network), the piedmont area was zoned and various susceptibility classes were detected. These results may represent a useful tool for studies aiming at territorial hazard mapping and civil protection interventions.

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Abstract. This study presents an historical database of flash flood events in the Campania region of southern Italy. The study focuses on small catchments characterized by intermittent flow, generally occurring during and after heavy rainstorms, which can be hydrologically defined as small Mediterranean catchments. As the outlet zones of these catchments (consisting mainly of alluvial fans or fan deltas) are highly urbanized in Campania, the population living in the delivery areas is exposed to high risk. Detailed scrutiny and critical analysis of the existing literature, and of the data inventory available, allowed us to build a robust database consisting of about 500 events from 1540 to 2015, which is continuously updated. Since this study is the first step of a longer project to perform a hazard analysis, information about time and site of occurrence is known for all events. As for the hazard analysis envisaged, collecting information about past events could provide information on future events, in terms of damage and also spatial and temporal occurrence. After introducing the issue of flash floods in Italy we then describe the geological and geomorphological settings of the study area. The database is then presented, illustrating the methodology used in collecting information and its general structure. The collected data are then discussed and the statistical data analysis presented.

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ad memoriam -This paper is dedicated to the beloved memory of our friend and collegue Paola Romano who unfortunately left us too early (Manuscript received January 20, 2016; accepted in revised form November 30, 2016) Abstract: The Quaternary evolution of the main coastal basins located along the southwestern margin of the Southern Apennines has been reconstructed by integrating the huge amount of existing stratigraphical and geomorphological data. The information produced in the last twenty years has shed new light on the recent (late Middle Pleistocene to Present) history of the Campanian and Sele plains or basins. During the early Quaternary, the analysed coastal basins originated as half-grabens in response to opening processes active since the late Tortonian in the southern Tyrrhenian back-arc basin. In some of these basins (e.g. the Campanian Plain), volcanism has also played an important role. In the inner sectors of the coastal basins, the complex interplay between block faulting, sedimentary inputs and glacioeustatic fluctuations gave rise to relative sea-level change and related coastline migrations, leading to the formation of the present-day coastal plains. In the Sele Plain basin, the construction of the present-day landscape mainly resulted from the substantial ceasing of subsidence in the final part of the Middle Pleistocene. Conversely, a strong contribution to the recent evolution of the Campanian Plain has been provided by abundant volcaniclastic aggradation, able to hinder the effect of the vertical motions that occurred in the last 100 ka.