Gypsum precipitation from deep seated brines trapped near the bottom of a rimmed basin was recently discovered in the eastern Mediterranean. The basin-named Bacino Bannock after an italian research vessel—is part of the outer flank of the Mediterranean Ridge, facing the Sirte Abyssal Plain. An acoustic reflector separates normal sea water from hypersaline anoxic water at approximately - 3.200 meters. Persistent anoxic conditions started to develop 180 000 y BP, as documented in sediment cores. The origin of the brines is accounted to submarine dissolution of Messinian evaporites, outcropping on the basin margin.
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Con il contributo del Ministero per i Beni e le Attività Culturali