The Messinian Salinity Crisis
The geological record contains many examples of large-scale accumulation of salt, yet there are few places today that provide appropriate modern analogues. In the recent geological past however thick halite deposits appear to have accumulated across the floor of the Mediterranean, the result of the "Messinian Salinity Crisis". The linked tectonic and climatic events that led to this remarkable episode are highly controversial. Geoscientists have argued as to the degree of sea-level fall, indeed, was the Mediterranean entirely dry for a period? Was evaporite accumulation synchronous or did different areas desiccate at different times? And how was the substrate configured to allow evaporites to accumulate?
Some of these questions were addressed during the completed on the "Central Sicilian Basins Project", an inter-disciplinary research programme run out of the University of Leeds. This web site gives a brief flavour of the results.
You can download a pdf essay on the subject by Rob Butler, first published in "Mercian geologist" (Butler, R. 2000. How the Mediterranean dried up. Mercian Geologist, 15, 62-65.)
You can also view and download photographs from the gallery.
The information that follows is based on this article, with diagrams attached.