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The coastal landscape of the Kachchh Upland (KU) region (NW-India) changed over the last few thousand years from a shallow marine gulf to a salty desert (1-4 meters asl). In this area, bordered to the south by the Northern Hill Range (NHR), the tectonic-climatic interaction triggered the sea level fall from +2/4 m circa (6000-2000 BP) to zero. An ancient river pattern deposited a tidally regulated delta area during the sea level fall that stopped 2000-3000 years ago due to tectonic activity and a dry climate. Deltaic-alluvial fans (DAF) in front of the NHR suggest that the KU's tectonic activity led to fast landscape evolution. We explored such drastic changes by integrating scientific information from a multidisciplinary literature review, identifying terraces and DAFs, and inferring faults through landform recognition, quantitative morphometry, and field surveys. Our interpretation, summarized in a map, provides new information on active processes along the NHR.

Atmospheric CO2 concentrations can reach high levels inside natural caves, representing a hazardous condition for both humans frequenting the underground environment and its safeguard due to the corrosion of speleothems induced by the acidification of atmospheric moisture. These issues are particularly critical for the eco-sustainable management of caves protected as nature reserves and undergoing touristic exploitation. In this paper we present the results of the C6 project, which was activated in 1999 for the monitoring of air quality inside three caves protected as nature reserves in Sicily (Italy). Near-real-time and spot measurements of air temperature and CO2 concentration have been carried out since the year 2000, giving the opportunity of evaluating the gas hazard for visitors and its potential impact on the protected underground environments, as well as the influence of meteorological and hydrological conditions in driving carbon dioxide accumulations. The analysis of data acquired in the hypogeal atmosphere, and their comparison with analogous epigeal measures, indicates that carbon dioxide accumulation is controlled by a complex interaction among cave topography, meteorological dynamics, gaseous exchanges between groundwaters and the atmosphere, and human fruition. This last factor, under particular conditions, can surprisingly diminishing underground CO2 concentrations.

160 km long hill ranges in the Kachchh region (NW-India) form a major E-W oriented topographic break delimiting the marshy plain of Banni in the North from the more elevated area of the Katrol Hill Range (KHR) in the south. Such topographic break is considered as the superficial expression of a quaternary active fault labelled Kachchh Mainland Fault (KMF). Numerous rivers cross this hilly region flowing roughly from South to North. The majority of those rivers are characterized by extensive fan lobes pinching out from the 200–300-meter anticlines of the hilly range.Starting from archaeological evidence from the past 4000-5000 years, it has been inferred that an extremely fast coastal landscape evolution brought such a region to evolve from an initial gulf landform to the current setting, i.e., the marshy plains of Banni and the salt-encrusted Rann. The location of the fans lobes marked the boundary between the fluvial and marine environments.High sedimentation rates varying between 1.1-2 mm/yr reported for the Banni plains together with historical and recent earthquakes (1668 Indus Delta, 1819 Allah Bund, 1845 Lakhpat, 1956 Anjar and 2001 Bhuj) provide valuable constraints for inferring the climatic and tectonic forcing on the region's quick dynamics.In our ongoing work, we propose a multidisciplinary approach made by morphotectonic mapping, morphometric analyses, and geochronology to understand better how the interplay of tectonics and eustatic perturbations drove such an abrupt landscape evolution.

Low Strain Rate regions (LSRr), i.e., areas deforming at a 1 mm/yr rate or less, represent the most globally widespread areas that host important cities and high-vulnerable anthropogenic assets. The occurrence of infrequent but high-magnitude earthquakes suggests that identifying active structures in the LSRr is one of the primary challenges for both the scientific community and modern societies.In such regions, one of the main issues in identifying active faults is the lack of useful outcrop data due to the anthropogenic and climate overprinting of the faults morphological signature. In this work, we propose a multidisciplinary approach designed to detect active geological structures and their related deformation. To test this approach, we selected as a natural laboratory an LSRr located between two major cities of Sicily (southern Italy). This area lies into the northern sector of the Apennine-Maghrebian fold and thrust belt and its offshore prolongation.Our approach consists of quantitative morphotectonic, offshore and onshore tectonostratigraphic and GNSS joint analyses. The main achieved results are 1) the first evidence of active, shallow-sited, NNW-trending transpressive blind faults that extends partially offshore for about 30 km, which décollement levels located at about 3 and 1 km depth, respectively and their 3D model, 2) a morphotectonic evolution model, that represents where and how these geologic structures drove the landscape evolution of the study area. Finally, we highlight that only a multidisciplinary approach could be useful for detecting and parametrising active faults in slow deforming areas that cross the coastline physical limit.

In the coastal sector of NW Sicily, the regional correlation of relevant unconformities recognised within the Quaternary sedimentary successions allowed the mapping of seven unconformity-bounded stratigraphic units (UBSUs). The regional unconformities are marine or subaerial erosional surfaces, as well as non-depositional surfaces, locally marked by paleosoils. The erosional surfaces were produced from marine abrasion, surface water overland/concentrated flow, river erosion, karst solution, mass movement, or wind erosion. The main lithofacies of the Quaternary UBSUs consist of: (a) marine and coastal bioclastic calcarenites, (b) aeolian sandstones, (c) river deposits, (d) colluvial deposits, (e) talus slope deposits, (f) landslide deposits, and (g) chemical carbonates (travertines and speleothems). Quaternary environmental changes, due to tectonics, climate, and sea-level oscillations, are the causes that favoured the development of erosion/deposition processes responsible for the genesis of unconformities and deposits. As a result, through the UBSU map of the NW Sicilian coastal belt, it is possible to: (i) recognise stratigraphic units controlled by tectonic, climatic, and environmental processes (and their interplay) and (ii) detect Quaternary sedimentary evolution.

Vulcano, the southernmost island of the Aeolian Archipelago, has been characterized by an intense fumarolic activity since its last eruption from La Fossa cone (1888-1890). This island has a strong touristic vocation and frequentation, and here volcano-hydrothermal activity represents, at the same time, a landmark, one of the main causes of hydrogeological instability and a severe risk for human health. The space-time dynamic of this complex system is controlled by the mutual interactions among micro-meteorological, volcanic, tectonic, morphogenetic and anthropic processes.La Fossa cone is affected by intense water erosion phenomena, also controlled by fumarolic activity as an obstacle for the growth of vegetation and a weathering factor. Man-made structures, with particular reference to deep modifications in the natural stream network induced by buildings and roads, exert a strong influence on these erosion processes, also fostered by episodic wildfires.Another relevant theme is the acceleration of the coastal erosion processes in the Baia di levante area, driven by the circulation of chemically-aggressive hydrothermal fluids, which transforms the pristine volcanic minerals into phases like gypsum, anhydrite and clay minerals, significantly reducing the mechanical resistance of the rocks to the action of wave erosion. A general retreatment of the coastline (several meters in some locations) has been observed in the last twenty years, caused by the combined effect of volcanic activity, anthropic modifications and changes in sea level.

The results of a geomorphological study carried out in the urban area of Palermo are summarized in a thematic map. Field survey, analysis of aerial photographs and topographic maps, consultation of historical documents and maps, stratigraphic and topographic reconstruction from numerous wells and subsoil data, and bibliographic search were performed, in order to display the geomorphological changes produced by man over time in a densely populated area and to define the Anthropocene of the study area. Palermo town rises along large marine terrace surfaces cut by small river valleys and bordered by wide degraded and abandoned coastal cliffs. Over the last 2700 years, this area was affected by remarkable man-made changes to topographic surface and underground, exposing large areas of the city to hydraulic, sinkhole, and landslide risks, and increasing the levels of seismic susceptibility. In light of these results, the produced map is useful for urban planning studies.

The isotopic signature of slow-flowing dripwater collected in caves located in Western Sicily (Italy) was determined for evaluating its possible use as an isotopic tracer of the local groundwater recharge. These spot measures were compared with a longer series of local rain and spring compositions and with other samples taken, under different hydrogeological conditions, in caves of the Harz Mountains (Northern Germany). The slow flowing dripwater from Sicily showed δ 18 O/δD ratios similar to those of local rain and groundwater, demonstrating that these three are all parent waters. A parallel similarity was found in the vertical isotopic gradient (Δδ 18 O) of the three groups of water, accounting for their common meteoric origin. In the colder Harz Region, dripwater, spring water and rain have the same δ 18 O/δD ratio but fast flowing dripwater, infiltrating through open cracks, is significantly enriched in lighter isotopes and representative of short residence time percolation. These results lead to the conclusion that dripwater, even if collected as spot samples, can be considered as a good isotopic marker of the average local groundwater recharge on the condition that only slow, diffused drips due to seepages are sampled.

The Capo San Vito peninsula is located along the north-westernmost sector of the Sicilian coastline. It is characterized by a complex geomorphological setting, where a large variety of coastal, gravity-induced and karst landforms allow the visitor to easily detect the interactions between Quaternary tectonics and climate changes as well as morphodynamic processes responsible for shaping the landscape. Thanks to natural reserves, the peninsula preserves a typical Mediterranean natural environment, marked by spectacular and suggestive landforms.