The Zanclean flood (also known as "Zanclean Deluge") is a flood theorized to have refilled the Mediterranean Sea 5.33 million years ago. This flooding ended the Messinian salinity crisis and marks the beginning of the Zanclean age. The term was coined by Maria Bianca Cita in 1972 during the Deep Sea Drilling Project study that investigated the transition between the Messinian and Zanclean ages in the Mediterranean.
According to this model, water from the Atlantic Ocean refilled the cut-off inland seas through the modern-day Gibraltar Strait. The Mediterranean Basin flooded over a period estimated between several months and two years (e.g. Roveri et al., 2008). Sea level rise in the basin may have reached rates at times greater than ten metres per day (e.g. Garcia-Castellanos et al., 2009). Based on the erosion features preserved until today under the Pliocene sediment, these authors estimate that water rushed down a drop of more than a kilometer with a discharge of up to 108 m3/s, about 1000 times that of the present day Amazon River. Studies of the underground structures at the Gibraltar Strait show that the flooding channel descended in a rather gradual way toward the bottom of the basin rather than forming a steep waterfall.
Not all scientific studies agree with the catastrophistic interpretation of this event. Many authors maintain that the reinstallment of a "normal" Mediterranean Sea basin following the Messinian "Lago Mare" episode took place in a much more gradual way.
In popular culture
Poul Anderson wrote the short story "Gibraltar Falls" (1975). Originally appearing in The Magazine of Fantasy & Science Fiction (October 1975), later collected in The Guardians of Time (1981) and several other collections, "Gibraltar Falls" is one of Anderson's Time Patrol stories. A romance set in Earth's distant past during the Zanclean Flood, the protagonist struggles with a time paradox regarding the coworker for whom he has feelings.
The Hugo-award-winning story Time, written by Randall Munroe as part of his webcomic xkcd, is set amid a hypothetical future repeat occurrence of the Zanclean Flood. In the story, two people living in the dry Mediterranean basin see the sea rising increasingly fast and go on an adventure to discover the cause:
The planet's mightiest river will once again come thundering down the mountainside. The sea will fill not in years but in days.
Julian May's Saga of Pliocene Exile is a science fiction series set at the time of the Zanclean flood, beginning with the period when the Mediterranean basin was dry land with a group of late 21st and early 22nd century misfits/outcasts who travel through a one-way time-gate to Earth's Pliocene epoch, in the hopes of finding a simple utopia where they can finally fit in. They discover that the Pliocene is already inhabited by a dimorphic race of aliens ('exotics'), the Tanu and the Firvulag who have fled their home galaxy because of religious persecution and are marooned on Pliocene Earth. The series describes the flood and events as and after the basin fills.
- Blanc, P.-L. (2002). "The opening of the Plio-Quaternary Gibraltar Strait: assessing the size of a cataclysm". Geodinamica Acta (15): 303–317. doi:10.1016/S0985-3111(02)01095-1.
- Nesteroff, Wladimir D.; William B.F. Ryan, Kenneth J. Hsu, Guy Pautot, Forese C. Wezel, Jennifer M. Lort, Maria B. Cita, Wolf Maync, Herbert Stradner and Paulian Dumitrica (1972). "Evolution de la sédimentation pendant le Néogène en Méditerranée d'après les Forages JOIDES-DSDP". University of Milan Institute of Geology and Paleontology Publication (in French) (125): 47–62.
- Garcia-Castellanos, D., Estrada, F., Jiménez-Munt, I., Gorini, C., Fernàndez, M., Vergés, J., De Vicente, R. (10 Dec 2009) Catastrophic flood of the Mediterranean after the Messinian salinity crisis, Nature 462, pp. 778–781, doi:10.1038/nature08555
- M. Roveri et al. (2008). "A high-resolution stratigraphic framework for the latest Messinian events in the Mediterranean area". Stratigraphy 5 (3-4): 323–342.
- "2014 Hugo Award Winners". The Hugo Awards. Retrieved 21 October 2014.
- Hudson, Laura (2 August 2013). "Creator of xkcd Reveals Secret Backstory of His Epic 3,099-Panel Comic". Wired. Archived from the original on 2013-10-11. Retrieved 3 August 2013.
- Media related to Messinian salinity crisis at Wikimedia Commons
- Gill, Victoria (9 December 2009). "Ancient Mediterranean flood mystery solved". BBC News. Retrieved 5 May 2013.
- "Dramatic flood filled Mediterranean Sea". World News Australia/Agence France-Presse. 10 December 2009. Retrieved December 2010.