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This paper presents the structural map of the Barrabisa Complex, an E-W ribbon-like migmatitic massif exposed in the northern part of Sardinia. The migmatites consist of metatexites and diatexites with variable melt proportion, grading in the central part of the complex to a foliated peraluminous granodiorite. Xenotime/monazite dating indicates that the foliated granodiorite pluton emplaced in upper Carboniferous times (≈307–313 Ma) within a narrow E-W ductile top-to-the east shear zone cutting through a Variscan high-grade metamorphic basement composed of orthogneisses, metasedimentary-derived migmatites and subordinate amphibolites. Field geological mapping, coupled with structural and micro-structural analysis, allowed us to distinguish the granodioritic pluton and three metamorphic units characterized by variable melt to protholith ratio, that represent a continuous transition from metatexite to diatexite with high melt concentration, to foliated granodiorite. [ABSTRACT FROM AUTHOR]

The spatial distribution of nuraghes throughout the Island of Sardinia still raises many questions. In this paper, we apply spatial statistical methods to investigate their relations with topographical features and with related objects nearby. We use the non-stationary G- and J-functions. To model interactions with topographic variables we use the non-stationary Poisson model. We find that the elevation of the nuraghes show a uniform distribution between 0 and 400 m, and with a peak in distances to holy wells of approximately 5 km. As expected, we found a clustered pattern, with clustering occurring in the mid-west, the centre and the south west of the Island. We further observed a very strong interaction with domus de janas, and a strong spatial interaction for distances in the range between 0 and 1000 m with the pre-Nuragic dolmens and menhirs, and the collective funerary structures, the so-called Nuragic giants' tombs. We conclude that the study is useful to quantify spatial patterns of pre-historic sites, in particular if these occur in a great abundancy and provides new insight into the spatial relations of the different pre-historic objects and buildings. [ABSTRACT FROM AUTHOR]

This paper aims to analyse to what extent the willingness to pay of art gallery visitors for the preservation of cultural artefacts is affected by the identity traits of the objects. To this purpose, we designed a discrete choice experiment that took place during a major exhibition dedicated to the artist Costantino Nivola (1911–1988) in Sassari (Sardinia, Italy). His works are known worldwide and many of them were produced after he moved from Sardinia to the United States in 1939. As a result, both the American and the Sardinian culture show up in his works and, in particular, were clearly visible in the exhibition under study. The discrete choice experiments allowed us to elicit respondents' preferences towards the identity features stemming from Nivola's artefacts. The results confirm the importance of this component indicating that its presence almost doubles respondents' willingness-to-pay for the acquisition of these artefacts to a permanent collection. [ABSTRACT FROM AUTHOR]

Using a comprehensive cartographic product, this paper aims to illustrate the evolution of the urban geomorphological setting of the urban coastal belt of Cagliari (southern Sardinia, Italy, western Mediterranean Sea). The geomorphological map (1:14,000) presented herein summarizes different data (e.g. urban development, anthropogenic features, geomorphological elements, recent deposits, sedimentological distribution, hydrodynamics and ecological components) acquired through an integrated sea-land approach and a multidisciplinary-multitemporal investigation. The main significant environmental changes are linked to urbanization, the development of port infrastructures (embankments along the shoreline and the construction of the canal harbour), remediation work and filling activities, and the hardening of dune and beach systems and cliffs. These man-made interventions have increased the vulnerability of the shore zones to flood hazards and risks, which are linked to sea-level rises and global warming. [ABSTRACT FROM AUTHOR]

In Italy, landslides are one of the main geological hazards. Sometimes urban areas are affected by deep-seated gravitational slope deformations (DGSDs) that can lead to a potentially catastrophic failure and trigger a secondary collateral landslide. In these cases, monitoring is important for early warning and risk reduction. In this study, we analyzed DGSDs, in particular, lateral spreads, and landslides in the inhabited areas of Ulassai, in eastern-central Sardinia. Starting from high-resolution geostructural and geomorphological surveys of lateral spread, integrated with high-resolution digital elevation models acquired by UAV (Unmanned Aerial Vehicle), we created geological 3D models of the slope deformations. To better understand the kinematics and temporal evolution of unstable slope deformation, a monitoring system, consisting of Space-borne Interferometric Persistent Scatter Synthetic Aperture Radar (PS-InSAR), GNSS antennas, tiltmeters, and extensometers, was performed. PS-InSAR analysis confirmed by GNSS periodic measurement identified downslope movement of up to 10 mm per year in the lateral spread. Continuous acquisition by extensometers and tiltmeter recorder displacement in large block inclinations and opening and closing of fractures since 2021. Integrated data analysis will be essential to define the threshold for a future 24/7 early-warning system. [ABSTRACT FROM AUTHOR]

We present a geomorphological map of the southwestern coast of Sardinia encompassing inland and offshore areas of the S’Omu e S’Orku Mesolithic site. The submerged area was documented by high-resolution multibeam bathymetry combined with Side-Scan Sonar data. The emerged coastal area was surveyed using Uncrewed Aerial Vehicle Remote Sensing and field surveys. The inland landforms were shaped by coastal, fluvial, and gravity-induced processes. Most of the submerged landforms appear be modeled in subaerial conditions during sea-level lowstands, and then sealed by the rising sea level. The coastal evolution has been characterized by the rapid cliff retreat facilitated intense linear erosion of watercourses, by debris flows, rockfalls and toppling. Geomorphological evidences of cliff retreat due to landslide was supported by a simplified analytic hydraulic model of the wavecliff interaction. These processes and the sea level rise canceled any possible Mesolithic settlement along the coast. The survival of the S’Omu e S’Orku site is only due to a protected morphological position and to the distance from the Early Holocene coastline. The dearth of coastal Early Holocene prehistoric sites is likely the outcome of the presented coastal dynamics. [ABSTRACT FROM AUTHOR]

The interaction of human dispersal patterns with landscape features can in many cases provide useful information on the sustenance strategies of past communities. Mapping the present landscape is a necessary step in recognizing the nature, impact, and diffusion of the processes which drive the behaviour of past populations and modify palaeolandscapes. We constructed a map of the land units in the southwestern corner of Sardinia and compared them with the distribution of known Bronze Age megalithic towers called nuraghes. The vast majority of nuraghes are near the plains or at mid elevations close to the river network, in areas with the highest landscape diversity. The occurrence of nuraghes also seems to be related to elevated outcrops giving the advantage of a raised position and stable foundations. Denudation processes, Late Holocene sea level rise, and anthropogenic disturbance seem to be the most important factors driving changes in the palaeolandscape. [ABSTRACT FROM AUTHOR]

This new map at 1:25,000 scale covers an area in the Western Alps (Italy), where the HP metamorphic basement is covered by a (predominantly clastic) late- and post-orogenic upper Eocene-lower Miocene cover. This provides unequivocal evidence that exhumation of the metamorphic units was accomplished by the lower Oligocene. The basement is made up of tectonic units with different metamorphic peaks that coupled during the exhumation path. Both basement and cover are affected by long-wavelength, asymmetric folds and thrust faults with top-to-E-NE vergence; this deformation phase has long been interpreted as linked to the rotation of the Corsica-Sardinia block and contemporary opening of the Liguro-Balearic basin and beginning of the Apennine orogeny. We particularly investigated some of these structures that crop out in the mapped area to give further constraints on their distribution, type and kinematics and to frame them in a larger picture of left-hand strike-slip tectonics. [ABSTRACT FROM AUTHOR]