Factors controlling cretaceous turbidite deposition in the Betic Cordillera

Abstract

The Cretaceous, turbiditic materials of the Betic Cordillera are to be found within different contexts. At the Southern Iberian Margin (the External Zones of the Betic Cordillera) the terrigenous turbidites are normally located in the Intermediate Domain, a subsiding area adjoining the southeast of the continental platform (Prebetic) and fed from the lberian continent. Lesser quantities of turbiditic facies exist locally in a thin-continental-crust area (Subbetic) lying further to the south and southwest. Considerable quantities of Cretaceous terrigenous turbidites were also deposited in the so-called North African "Flysch Trough", a deep elongate basin with an oceanic or sub-oceanic crust substrate. This trough provided a communication between the Tethys and the Atlantic and their sedimentary source areas were the continental reliefs of the African plate and the Mesomediterranean subplate. Both the beginning and the end of turbiditic sedimentation at the Southern Iberian Margin and the North African Flysch Trough, more or less coincided. The terrigenous turbidites occur generally between the Hauterivian and the Albian at times of brusque falls in sea level (lntra-Hauterivian, lntra-Aptian, Intra-Albian), which caused the erosion of the adjacent platforms. There are also other small quantities of turbidites, both terrigenous and carbonate, from various ages during the Cretaceous, connected to local tectonic activity and/or relative falls in sea level.