The end of the Mediterranean Messinian Salinity Orisis: The Zanclean Flooding

Ferran Estrada, Gemma Ercilla, Christian Gorini, Belen Alonso, Juan-Tomas Vazquez, Andres Maldonado, and Abdellah Ammar

The end of the Mediterranean salinity crisis was abrupt and occurred through the Gibraltar gateway by means of a huge Atlantic water flooding (the Zanclean flooding). A very detailed characterization of the Messinian top surface of the Alboran Basin (Western Mediterranean), based on the stratigraphic study of a dense net of single-and multi-channel seismic records as well as their correlation with scientific and commercial wells, has allowed establishing that the most prominent feature formed by the Zanclean flooding is a huge erosional channel-like feature (390 km length), which crosses the entire basin along its deeper parts. The present-day section of the Gibraltar Strait basically formed during the Zanclean flooding and westward connects with the erosive channel-like feature. Its entrenchment was greater in the Western Alboran Basin where the direct impact of the Atlantic water mass was stronger. The regional basin topography and local presence of highs (structural, volcanic, and diapiric in origin) controlled the main flooding pathway and local variations in erosive capacity of the Atlantic water. Other morphosedimentary features, as subaereal canyons and terraces at different water depths, indicate different phases of Atlantic water inflow into the Alboran Sea.

AAPG Search and Discovery Article #90161©2013 AAPG European Regional Conference, Barcelona, Spain, 8-10 April 2013