Active degassing across the Maltese Islands (Mediterranean Sea) and implications for its neotectonics

Gas - Escape features along the Trzebiatów fault offshore Poland: Evidence for a leaking petroleum system

“…These sands could possibly be potential deposits of the free gas in Pleistocene sediments. The pockmarks identified by multibeam data (Figure 7) and enhanced reflection features identified surrounding the gas effects illustrate simultaneous free gas accumulation and seafloor leakage (Micallef et al, 2019).…”

Past and future evolution of the onshore-offshore groundwater system of a carbonate archipelago: The case of the Maltese Islands, central Mediterranean Sea

“…Geomorphology is primarily controlled by tectonic activity, with mass movements, karstification, surface water and coastal erosion playing a secondary role (Alexander, 1988). The seafloor area considered for this study (i.e., from the coast down to a depth of 120 m; Figure 1) represents a submerged paleolandscape that is up to 10 km wide, gently sloping and hosting valleys, karstic landforms, paleoshorelines and deposits along the east (Micallef et al, 2013(Micallef et al, , 2019. Along the west, the shelf is comparably narrower.…”

“…Onshore geological data for the Maltese Islands comprised: (i) a digital elevation model of the entire Maltese archipelago (1 m cell size; acquired during a 5.5 h flight in February 2012 using an IGI LiteMapper 6800 LiDAR system as part of the project "Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys" funded by ERDF-156), (ii) a surface geological map (Pedley et al, 1976), and (iii) legacy and recent borehole logs (Costain and Messers, 1957;De Biase et al, 2021). Offshore geological data included: (i) multibeam echosounder data acquired offshore the eastern coast of the Maltese Islands during a number of expeditions (Micallef et al, 2013(Micallef et al, , 2019, (ii) >400 km 2 of bathymetric data acquired with a Hawkeye IIb bathymetric LiDAR sensor and an interferometric swath system (Kongsberg GeoSwath), collected as part of the project "Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys" funded by ERDF-156, (iii) bathymetry from the remaining seafloor derived from EMODnet Bathymetry (https://www.emodnet-bathymetry.eu/), (iv) multichannel seismic reflection profiles, and (v) offshore boreholes and seafloor samples (as described in Micallef et al, 2019;Haroon et al, 2021).…”

Coupling long-term GNSS monitoring and numerical modelling of lateral spreading for hazard assessment purposes

“…At Anchor Bay, the analysed section runs in a N-S direction close to GNSS benchmarks 102 and 105. The scarp and toe limits for the search algorithm were imposed after field surveys while the solid Globigerina Limestone basement was assumed to be 10 m below the sea level (inferred from Prampolini et al, 2017, andMicallef et al, 2019). The mechanical properties of each formation used in the analysis are summarized in Table 4.…”