El Chorro is Famous for the three artificial turquoise coloured lakes that were created when the dam was built across the Guadalhorce river gorge, this spectacular gorge known as the Garganta del Chorro regularly has eagles soaring high above the cliffs.
There is a small bridge across the gorge named the Camino del Rey (The Kings Path), as this mammoth engineering project was open in 1924 by King Alfonso XIII of Spain.
The steep walls of this gorge are vertical beds of limestone. The age of these rocks are not a problem - marine fossils place them accurately in the Jurrassic era. Ammonoids contained in them in particular allow the dating of some of these beds with an accuracy of about 1 million years.
Messinian marine deposits of the Guadalhorce River valley in southern Spain record evidence of the last northern gateway that existed between the Mediterranean and the Atlantic. They comprise sandstones and conglomerates with unidirectional cross-bed sets up to nearly 1 km long in their down-sedimentary-dip direction. These cross-bed sets relate to extremely fast (1.0-1.5 m s-1) bottom currents flowing from the Mediterranean into the Atlantic. The Guadalhorce gateway (which had a maximum width of 5 km and a maximum water depth of 120 m) was an important element controlling the Messinian pre-evaporitic oceanic circulation in the Mediterranean Sea, as it acted as a major outflow channel. Its closure limited the exchange of water between the Atlantic and the Mediterranean to the Rifian corridors of Morocco, inducing water-mass restriction and stratification in the western Mediterranean immediately prior to the `Messinian Salinity Crisis'.
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