Sara Biolchi

Geomorphological map of the NW Coast of the Island of Malta (Mediterranean Sea)

This paper presents the results of geomorphological investigations carried along the north-western coast of the Island of Malta. Field surveys, accompanied by aerial photo-interpretation, have led to the production of a geomorphological map at 1:7500 scale which outlines the main processes and related landforms. The latter are the result of the complex interplay of structural, gravitational, coastal and karst processes. Particular attention was devoted to the recognition, identification and mapping of landslides which affect large coastal sectors of the study area, locally giving rise to hazardous conditions.

Geology of the Classical Karst Region (SW Slovenia–NE Italy)

ABSTRACT The paper aims to present the geology of the western part of the Classical Karst (NW Dinarides), located at the border between Slovenia and Italy. The work is based on archive, published and new data collected by Slovenian and Italian researchers within several scientific national and Cross Border Cooperation projects. The map, produced at a scale of 1:50,000, summarizes the lithological and structural setting and is supplemented by three geological cross-sections of the study area.

Geomorphological identification, classification and spatial distribution of coastal landforms of Malta (Mediterranean Sea)

This paper presents the outcomes of a geomorphological investigation carried out along the coasts of the island of Malta and provides a detailed classification of the Maltese coastline based on the identification and definition of specific coastal geomorphotypes. The results of field surveys, supported by air-photo interpretation, have led to the production of a coastal geomorphological map at 1:30,000 scale which outlines the processes and related deposits and landforms. The latter are the result of the complex interplay of structural, gravitational, coastal and karst processes. Moreover, radiocarbon dates of marine organisms encrusted on boulders mapped along the NE coast are presented.

Landslides Along the North-West Coast of the Island of Malta

The paper shows the results of geomorphological and engineering-geological investigations carried out along the north-western coast of the Island of Malta, with special emphasis on landslides. Field surveys and aerial-photo interpretation allowed the recognition, identification and mapping of a series of landslides of different type and size, some of which showing evidence of activity. Coastal instability in the studied area is deeply controlled by structural factors, such as tectonic and stratigraphic ones. The research envisaged a multidisciplinary approach, which also included landslide monitoring in specific sites which were selected for detailed investigations, owing to the peculiarity of the instability processes occurring and for the related hazard and risk conditions. The paper outlines the research phases and the results achieved which proved to be fruitful thanks to the application of different methodologies for the study of coastal landslides. Particular attention has been paid to rock spreading phenomena, which are widespread along the north-western coast of Malta due to the superimposition of limestones over clayey terrains.

Morphoneotectonics and lithology of the eastern sector of the Gulf of Trieste (NE Italy)

ABSTRACT The paper aims to describe and map the geomorphological and lithological features of the Gulf of Trieste and its eastern coasts and to define its neotectonic behaviour by means of the analysis of the morphoneotectonic evidence. The final map, produced at a scale of 1:30,000, shows the outcome of field investigations carried out along the coast and the sea bottom and a detailed geomorphological classification of the coastline. Published and new data coming from the analysis of archaeological remains, geomorphological and sedimentological sea-level indicators and geophysical researches are discussed in order to provide a complete overview of the study area.

Geomorphological mapping of terrestrial and marine areas, northern Malta and Comino (central Mediterranean Sea)

ABSTRACT This paper presents an integrated geomorphological map of terrestrial and marine areas of northern Malta and Comino (central Mediterranean Sea) at 1:25,000 scale. The map is the result of terrestrial and marine analyses of different types of data such as aerial photos, digital terrain model of the seafloor and its acoustic backscatter image. The research is intended to emphasise the relationships and continuity of geomorphological features of both the land- and sea-scape, and outline their evolution. The map highlights the occurrence of fluvial, karst and gravity-induced landforms both on land and on the seafloor, such as palaeo-fluvial channels, sinkholes and landslides, which were shaped during sea level lowstands of the last glacial cycle.

Intrinsic vulnerability of the Isonzo/Soča high plain aquifer (NE Italy – W Slovenia)

ABSTRACT The paper presents the map of intrinsic groundwater vulnerability of the Isonzo/Soča High Plain, which is located between the Collio Hills and the Classical Karst Region and holds an aquifer shared between Italy and Slovenia. The map, produced at a scale of 1:25,000 and printed in A0 format, was obtained by means of the SINTACS method and shows the intrinsic vulnerability of the aquifer in terms of seven vulnerability classes, from extremely high to low. It is accompanied by four supplementary sketches that illustrate the geological framework, the bedrock top surface, the groundwater flow paths, the Hazard Index map and three diagrams that summarize the percentages of vulnerability classes and of Hazard Index classes of the study area.

The Karst Hydrostructure of the Mount Canin (Julian Alps, Italy and Slovenia)

The Mt. Canin massif, from a hydrogeological and geomorphological point of view, is a unique structure, being an independent part of the Italian Julian Alps (north east Italy) bounded on all sides by impressive karst springs. Extensive outcropping limestones go from the top (2587 m a.s.l.) to the bottom of the valleys (about 500 m a.s.l.) creating an hydrostructure subdivided between two countries originating two transboundary watersheds: the Mediterranean one to the South and the Black Sea to the North. The aim of this paper is to define the dynamic and the characteristics of the groundwaters and to identify the superficial and deep watersheds in order to elaborate the aquifer vulnerability.

Factors Triggering Sea Cliff Instability Along the Slovenian Coasts

ABSTRACT FURLANI, S., DEVOTO, S., BIOLCHI, S and CUCCHI, F., 2011. Factors Triggering Sea Cliff Instability Along the Slovenian Coasts. In: Micallef, A. (ed.), MCRR3-2010 Conference Proceedings, Journal of Coastal Research, Special Issue, No. 61, pp. 387–393. Grosseto, Tuscany, Italy, ISSN 0749-0208. The cliff retreat is the sum of the sustained action of marine and continental factors. Their interrelations depend on the geological and environmental settings of the area. The studied cliffs are cut in the Eocene Flysch, a turbiditic succession composed by centimetric—metric sandstones with millimetric-centimetric interbedded silty marlstones, almost horizontal in the study area. The low resistance of the rock mass allows the rapid retreat of the cliffs and the development of wide shore platforms. This work aims at evaluating sea cliff retreat and the factors that trigger the collapse of material and its removal from the cliff foot. Different methods have been used: a detailed characterization of the geomechanical properties and the quality of rock masses, the susceptibility to rock falls and a photographic surveying. The sea cliff retreat in five sites along the Slovenian coast, in the Northeastern Adriatic Sea, has been studied through the comparison of more than 7000 pictures collected since 1998, at precise time steps and under any weather conditions. These data have been subsequently compared with archaeological data, historical maps and the characterization of the geomechanical features of rock masses in order to determine the factors triggering the cliff retreat. Photographic surveying displays a rapid but complex behaviour of the cliff retreat: during long stable-weather periods, cliff modifications are very low and groundwater solution or landslides have been observed. Major changes in the cliff face have been observed after great storm events, because of a complex interaction between marine and non-marine factors. The integrated method proposed here, including the photographic surveying and the geomorphological-geomechanical characterisation of rock masses is a valuable method for understanding and evaluating the mechanisms of cliff retreat.

Rock Fall Characterization in Climbing Spots: The Case Study of the “ Napoleonica ” Tourist Route (Trieste, NE Italy)

In NE Italy, fast-moving landslides represent a significant threat both to the population and the built environment. In the eastern portion of the Italian Alps, rock falls are common and are often responsible for casualties or severe damage to infrastructure. This type of landslide is characterized by strong relief energy and is triggered by earthquakes or copious rainfall, which often exceeds 2000 mm/yr. To assess rock fall hazard using software analysis, field surveys are crucial to accurately recognize the source areas of falling rock phenomena, to quantify the volumes of unstable blocks and identify the possible block trajectories. The current work takes in detailed geological and geomorphological mapping, through the identification of dislodged blocks, fractures and fallen blocks on a much-frequented limestone cliff in the Trieste Karst used as a climbing spot. Moreover, a popular tourist path (the Napoleonica) lies at the foot of the climbing cliffs. In-depth traditional activities, such as field surveys and aerial photo analysis were undertaken, including morphometric and geomechanical characterization of the whole rock mass, in order to perform a first identification of the more hazardous sections of the Napoleonica. The field data were collected using UAV (Unmanned Aircraft Vehicle) images and videos and this innovative technique allow the reaching and study of difficult sites with excellent resolution and precision. The final output is a GIS-developed map, that will be the starting point for future 2D and 3D simulations, that will lead to the creation of a rock fall susceptibility evaluation of the whole area.