This study investigates the architecture and structural setting of the Sciacca Fault System (SFS), a key component of the Sciacca Geothermal Field in southwestern Sicily, through an integrated geological and geophysical approach. The analysis correlates the offshore SFS lineament with the onshore Mt. Kronio fault system to assess their role in regional deformation and geothermal connectivity. Seismic reflection data reveal a NE–SW oriented transpressive fault network characterized by thrusts and positive structures, with evidence of recent compressive deformation affecting both Upper Calabrian deposits onshore and Late Pleistocene–Holocene sequences offshore. High-resolution profiles show active fluid migration, suggesting a hydraulically connected onshore–offshore geothermal system. A 3D reconstruction of the fault network defines the geometry and extent of the geothermal reservoir and supports a fluid migration model involving a northward and upward flow from a deep source in the offshore sector. Fluids are channelized within fault-bounded compartments sealed by low-permeability surfaces and capped by pelagic units, forming a partial structural trap. Vertical migration culminates where the carbonate substrate is exposed, as at Mt. Kronio, while offshore fluid ascent follows permeable faults and discontinuities within the sedimentary cover.

Among microplastic, plastic pellets (2-5 mm in size), represent the most abundant pollutants in coastal environment. Although plastic pollution in the Mediterranean Sea has been extensively investigated, the occurrence of plastic pellets within beach sediment remain poorly documented.,In this study, a sedimentological approach was applied to investigate the transport, sedimentation and burial of plastic pellets in three Sicilian sandy beaches (Mediterranean coast). A new sampling method is used to detect the presence of plastic pellets from the beach surface to a depth up to 1 m, exceeding the depth currently reached by other studies. The vertical distribution of plastic pellets throughout the sediment column, demonstrates that they behave as sedimentary particles and undergo the same transport and depositional processes as natural sediments. The highest pellet concentrations were recorded within storm berms and at the dune base, identifying these sectors as the main accumulation and long-term burial zones. The observed horizontal and vertical distributions are consistent with a conceptual model involving storm-driven deposition, subsequent redistribution across the backshore, and progressive burial within dune system. This study demonstrates that conventional surface monitoring of beaches underestimates the amount of plastic stored in the coastal environment.

Marine tidal notches (MTNs) are widely recognized as reliable indicators of mean sea level and have been extensively used along carbonate coasts of the Mediterranean Sea, where tidal ranges are generally small, to reconstruct relative sea-level changes. MTNs develop primarily through the combined effects of carbonate dissolution associated with the interaction between marine and meteoric waters, bioerosion by intertidal organisms, and mechanical removal of weathered material by wave action. Previous studies have demonstrated that notch morphology reflects a combination of tidal range, lithology, and cliff-toe depth, while significant freshwater discharge may enhance notch development. In microtidal Mediterranean settings, the morphology and elevation of MTNs are therefore closely related to local sea-level conditions. Detailed surveys of MTNs throughout the Mediterranean have documented both typical tidal notches and anomalous morphologies. Among the latter, notches developed within ria-type coastal settings may progressively deepen from exposed to increasingly sheltered environments, producing landforms referred to as dipping marine notches (DMNs). Here, we investigated two sea caves in northwestern Sicily (central Mediterranean Sea), where contrasting notch shapes are preserved. At Capo Zafferano Cave, a present-day tidal notch progressively transforms into a dipping marine notch within less than 20 m of the cave entrance, whereas at Cala Rossa Cave a submerged notch remains closely associated with the corrected sea level, with repeated measurements ranging from 0.00 to −0.10 m. We evaluate the possible role of freshwater spring discharge in its formation and preservation. High-resolution geomorphological measurements were collected during repeated field surveys and corrected for short-term tidal variability using the Palermo tide-gauge record. The repeated measurements were quantitatively assessed using statistical analyses accounting for the repeated-measures structure of the dataset. Water-temperature measurements at Cala Rossa revealed a marked thermal anomaly, with temperatures reaching 25.0 °C in the freshwater-influenced inner sector compared with 28.8 °C at the cave entrance, consistent with the presence of a distinct freshwater-influenced water mass within the cave. Ecological and biological information were presented as a description of the study sites, providing a biotic context for the observed tidal notches. The results provided quantitative evidence for the reproducibility of the observed notch positions under different tidal conditions and support the interpretation of contrasting notch shapes as the result of different hydrodynamic and geomorphological processes. These findings highlight the importance of freshwater discharge, cave confinement, and local hydrodynamic conditions in controlling the development and preservation of tidal and submerged notches in Mediterranean carbonate coastal environments.