Fluid flow systems of the Malta Plateau, Central Mediterranean Sea

Intra- to post-Messinian deep-water gas piping in the Levant Basin, SE Mediterranean

“…Normal faults are capable of serving dual roles as conduits or as hydraulic barriers to fluid flow, depending on the magnitude of dilation of the shear zone and the overburden lithology. Greater shear strain increases transient permeability promoting fluid transport from deeper sources (Aydin, 2000;Berndt, 2005;Micallef et al, 2011). More also, compression associated with halokinetic forces is likewise capable of compromising the shear integrity of sedimentary units and the accompanying joints may also enhance permeability, and consequently the localized fluid flow (sensu Bonini, 2012).…”

“…Beyond the risk associated with seal failure as these pipe structures breach the regional sea (the Messinian evaporite), it is likewise crucial to stress that this region of deformed overburden strata may have reduced geotechnical integrity. This reduced integrity may arise consequent of the localised fluid flow that compromises sediment shear strength (Andreasen et al, 2007;Micallef et al, 2011) and also localised enhancement in petrophysical qualities (i.e. permeability) within the significantly anisotropic overburden succession.…”

“…Fluid flow is a dynamic and ubiquitous process manifested in varying intensities across sedimentary basins worldwide (Andreassen et al, 2007;Judd and Hovland, 2007;Micallef et al, 2011;Andresen, 2012;Anka et al, 2012Anka et al, , 2013. Evidences for episodes of fluid flow (pore waters, gas, oil or all combined) in sedimentary successions are identified on subsurface geophysical datasets as diverse seismo-geomorphologic structures encompassing pockmarks, chimneys, mud volcanoes, intrusions and pipes, each exemplifying the nature of the flow (e.g., Cartwright, 2007;Gay et al, 2007;Judd and Hovland, 2007;Løseth et al, 2009;Ostanin et al, 2013;Vadakkepuliyambatta et al, 2013).…”

“…The Messinian evaporite unit exerts major control on basin fluid flow across the Mediterranean (Lastras et al, 2004;Cartwright, 2005, 2014;Gradmann et al, 2005;Zitter et al, 2005;Netzeband et al, 2006b;Camerlenghi and Pini, 2009;Clari et al, 2009;Hübscher et al, 2009;Micallef et al, 2011;Iadanza et al, 2013;Natalicchio et al, 2013;Mascle et al, 2014). Although the Messinian evaporite serves as regional seal (Bertoni and Cartwright, 2005;Gardosh and Tannenbaum, 2014), there are compelling evidences documented over the last decade suggesting fluids bypassing this supposedly sealing sequence albeit most of which have been documented along the Northern and Southern Levant margin (Bertoni and Cartwright, 2005;Frey-Martinez et al, 2005b;Fuhrmann, 2010;Netzeband et al, 2006b;Reiche et al, 2014).…”

Authigenic minerals from the Paola Ridge (southern Tyrrhenian Sea): Evidences of episodic methane seepage

“…In the western part of the central Mediterranean Sea, the Tyrrhenian Sea, evidences of fluid seepage are limited to the Adriatic Sea (Geletti et al, 2008), Strait of Sicily, Sardinian Margin (Dalla Valle and Gamberi, 2011) and Malta Plateau (Savini et al, 2009;Micallef et al, 2011;Taviani et al, 2013), mostly in the form of pockmarks, occasionally associated with methane-imprinted carbonates (Capozzi et al, 2012;Cangemi et al, 2010;Angeletti et al, 2015;Taviani et al, 2015). In the westernmost part of the Central Mediterranean Sea, the Tyrrhenian Sea, little evidence of past and present fluid circulation was found in the deep sea, except for the Paola Ridge, along the NW Calabrian margin (Fig.…”