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A recent geo-marine survey of the Malta Escarpment revealed for the first time the existence of live cnidarian assemblages at about 300 m depth. These associations have been observed by means of a remotely operated vehicle (ROV) during surveys carried out on the upper part of the Malta Escarpment. The assemblages established on hard bedrock were chiefly composed of the antipatharianLeiopathes glaberrima. The Malta Escarpment is known to have been successfully colonised by deep-water scleractinian assemblages until the last glacial age. However, no living specimens had been observed, and only specimens of dead but relatively freshDendrophyllia cornigerahad been reported. This area of the Mediterranean Sea, which connects the deep Ionian basin to the western Mediterranean, is largely unknown and in clear need of thorough exploration. [ABSTRACT FROM AUTHOR]

The phenomenon of insular dwarfism in proboscideans is particularly well represented on the Siculo-Maltese Palaeoarchipelago, an island group on which a species complex of palaeoloxodont elephants evolved during the Middle-Late Pleistocene. This likely included three species from Malta, four from Sicily (and possibly its palaeo-islands), and one from Favignana Island, ranging in size from the 1 m-tall Palaeoloxodon falconeri to continental-sized 4m-tall P. antiquus. However, our understanding of the causes for extreme differences in body size among insular samples in such a small geographic region is still limited. Here, I document the full range in size of elephants from the palaeoarchipelago, and discuss the reasons for size differences on the three islands in time and space in relation to predation, competition, resource limitation, accelerated life history, and duration of isolation. Differences in size between larger and smaller Sicilian elephants from Luparello Fissure, as well as possibly also in P. ex gr. P. mnaidriensis from Puntali Cave, San Teodoro Cave, and Favignana Island, may relate to the duration of isolation, or alternatively environmental stressors associated with the Last Glacial Maximum in the case of the Favignana elephant. Additionally, small but significant differences in size observable in Middle Pleistocene P. ex gr. P. falconeri from different localities on Sicily, as well as in Maltese P. 'melitensis' may also relate to duration of isolation, highlighting the need for better geochronological data in order to better distinguish macro-ecological causes driving body size change from more subtle effects relating to duration of isolation. [ABSTRACT FROM AUTHOR]

Carbonate lithologies host considerable quantities of the Earth's freshwater resources and partially supply a quarter of the global population with drinkable water. In addition, carbonates constitute substantial amounts of the global coastlines, yet it is not known if and how they can sustain freshened groundwater offshore. Here, we use controlled‐source electromagnetic, seismic reflection, and core sample data to derive a lithological model for the eastern margin of the Maltese Islands and identify four distinct resistivity anomalies within the Upper Coralline and Globigerina Limestone formations. The anomalies hosted in the former are likely associated with low porosities, whereas the anomaly within the latter is indicative of pore fluid freshening. Hydrogeological modeling suggests that freshened pore fluids, emplaced during sea‐level lowstands and preserved in low permeability units, are potentially still found within carbonate shelves. However, resource potential is low due to its relict nature and low permeability host environment. Plain Language Summary: Coastal regions with freshened groundwater beneath the seafloor are found worldwide. Here, we report on a geophysical study conducted off the eastern coastline of the Maltese Islands, where a number of resistivity anomalies are observed in limestones. The anomalies located offshore southeast Malta are likely associated with freshened groundwater. Hydrogeological modeling suggests that this groundwater was deposited during lower sea levels and preserved in fine‐grained units. Our study indicates that offshore freshened groundwater may be found offshore limestone coastline in dry climates, but its potential to be used as a source of freshwater is likely low. Key Points: Geophysical data and hydrogeological modeling are applied to detect offshore freshened groundwater in a semi‐arid carbonate settingGlobigerina Limestone and Blue Clay located offshore SE Malta likely host a disconnected offshore freshened groundwater bodyThe resistive anomalies within the Upper Coralline Limestone are interpreted as localized porosity variations [ABSTRACT FROM AUTHOR]

This paper presents a geomorphological map of the seafloor north east of the Maltese Islands (Central Mediterranean) at a scale of 1:50,000. The map was compiled following the integration, analysis and interpretation of several high-resolution seafloor bathymetry datasets. Several structural features, coastal and marine landforms and anthropogenic features have been mapped. Most of the mapped submerged landforms - including fluvial, gravity-induced and karst landforms - appear to have been formed during the sea-level lowstand of the last glacial cycle. The map provides valuable insights on the submerged landscape of the Maltese Islands and its evolution since the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The tsunami hazard for the Maltese Islands is poorly defined, and historic records are available for only two recent events. Most of the population and touristic infrastructure of the archipelago is concentrated along the eastern low-lying coastline, which is exposed to tsunamis from near-field and far-field sources. In this study we present a scenario-based tsunami inundation study to assess the impact of potential significant cases. We simulated four scenarios—two submarine landslide sources (outer Malta Plateau slide and Gela Basin slide) and two earthquake sources mimicking events comparable to the 365 A.D. western Hellenic Arc event and the 1693 south-east of Sicily event. We find that all scenarios cause inundation in densely populated low-lying bays or rias of Mellieha Bay, Xemxija, Salini, Gzira, Msida, Marsaskala, St Thomas Bay, Marsaxlokk and Birzebbuga. The largest inundation extents and flow depths (> 10 m) are produced by the two landslide sources and the western Hellenic Arc earthquake. Of interest is the role of the Malta Escarpment and Sicily in amplifying and reflecting tsunami waves, and in generating consistent hot spots along the eastern coastline of Malta. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) geophysical methods are well equipped to distinguish electrical resistivity contrasts between freshwater-saturated and seawater-saturated formations. Beneath the semi-arid, rapidly urbanizing island of Malta, offshore groundwater is an important potential resource but it is not known whether the regional mean sea-level aquifer (MSLA) extends offshore. To address this uncertainty, land-based alongshore and across-shore time-domain electromagnetic (TDEM) responses were acquired with the G-TEM instrument (Geonics Ltd., Mississauga, ON, Canada) and used to map the onshore structure of the aquifer. 1-D inversion results suggest that the onshore freshwater aquifer resides at 4–24 m depth, underlain by seawater-saturated formations. The freshwater aquifer thickens with distance from the coastline. We present 2D and 3D electromagnetic forward modeling based on finite-element (FE) analysis to further constrain the subsurface geometry of the onshore freshwater body. We interpret the high resistivity zones that as brackish water-saturated bodies are associated with the mean sea-level aquifer. Generally, time-domain electromagnetic (TDEM) results provide valuable onshore hydrogeological information, which can be augmented with marine and coastal transition-zone measurements to assess potential hydraulic continuity of terrestrial aquifers extending offshore. [ABSTRACT FROM AUTHOR]

The coastal landscape of the Maltese Islands is the result of long-term evolution, influenced by tectonics, geomorphological processes, and sea level oscillations. Due to their geological setting, the islands are particularly prone to marine-related and gravity-induced processes, exacerbated by climate change. This study aligns different concepts into a relatively concise and expedient methodology for overall coastal vulnerability assessment, taking the NE sector of Gozo Island as a test case. Geomorphological investigation, integrated with analysis of marine geophysical data, enabled characterization of coastal dynamics, identifying this stretch of coast as being potentially hazardous. The study area features a high economic value derived from tourist and mining activities and natural protected areas, that altogether not only make coastal vulnerability a major concern but also the task of assessing it complex. Before introducing the methodology proposed for overall vulnerability assessment, an in-depth revision of the vulnerability concept is provided. The evaluation was carried out by using a set of key indicators related to local land use, anthropic and natural assets, economic activities, and social issues. Results show that the most critical areas are located east of Marsalforn including Ramla Bay, an important tourist attraction hosting the largest sandy beach in Gozo. The method combines physical exposure and social vulnerability into an overall index. It proves to be cost effective in data management and processing and is suitable for the identification and assessment of overall vulnerability of coastal areas to consequences of climate- and marine-related processes, such as coastal erosion, landslides and sea level rise. [ABSTRACT FROM AUTHOR]

The recognition, selection and quantitative assessment of sites of geological and geomorphological interest are fundamental steps in any environmental management focused on geoconservation and geotourism promotion. The island of Malta, in the central Mediterranean Sea, despite having a steadily increasing growth in population and tourism, still conserves geological and geomorphological features of great relevance and interest, both for their contribution to the understanding of the geological processes acting through time on landscape and for their aesthetic importance. The present work proposes an inventory for northern Malta, through three main stages, with the outcome of a final list of geosites that have the potential to be recognized as both natural heritage and tourist resources with potential economic benefits. In particular, the assessment methodology applied combines scientific value and additional and use-values, showing the links existing between geoheritage and other aspects of nature and culture of the sites. The results provide useful knowledge for the definition of strategies aimed at the development of a sustainable and responsible tourism. [ABSTRACT FROM AUTHOR]

Malta and Sicily, which lie at the centre of the Mediterranean Sea, share a long history and have unique geological and geomorphological features which make them attractive destinations for geotourism. In the framework of an international research project, a study for the identification, selection and assessment of the rich geological heritage of Malta and Sicily was carried out, aiming to create a geosite network between these islands. Based on the experience and outputs achieved in previous investigations on geoheritage assessment carried out in various morpho-climatic contexts, an integrated methodology was applied for the selection, numerical assessment and ranking of geosites. The selection phase was based on three main criteria—scientific, additional and use values—and led to the establishment of a list of 42 geosites (20 in Malta and 22 in Sicily). Besides being spectacular and attractive for tourists, these sites represent the main geomorphological contexts and the various stages of regional morphogenesis of the study areas. The sites selected were assessed quantitatively and ranked according to management and tourism criteria. The results provide both the necessary basic knowledge for joint conservation actions and policies in Malta and Sicily and the elements for creating a link between Malta and Sicily through geoheritage appraisal and tourism development. [ABSTRACT FROM AUTHOR]