The Interface Between Tectonic Evolution and Cold-Water Coral Dynamics in the Mediterranean

Abstract

Circulation and water properties in the Mediterranean basin, and thus the living conditions for marine biota, including cold-water corals, are a strong function of the connectivity of the basin with neighbouring water masses. The configuration of the basin and its connections with adjacent basins are governed by the interplay of large scale and regional scale geodynamical (or tectonic) processes within the Mediterranean region. As to surface area, it appears that the Mediterranean basin as a whole is closing whereas some of its sub-basins are opening, at the expense of the eastern Mediterranean basin. More important are opening or closure of gateway connections. The pertinent Mediterranean gateways to the Atlantic Ocean and the Black Sea are potentially subject to minor changes resulting from tectonics. However, the impact of such possible changes on marine conditions, including those for cold-water corals, would be slow and of minor magnitude compared to the effects of climate change. Typical aspects of cold-water coral occurrences in the Mediterranean region, notably the uplift and outcrops of Plio-Pleistocene communities and the presence of steep faults (with steered fluid seeps providing nutrients) as preferred production areas, are accounted for by vertical motions in subduction zone evolution.