Middle Eocene carbonate platforms of the westernmost Tethys

A study of the paleoenvironmental evolution middle Eocene platforms recognized in westernmost Tethys has been carried out well-exposed succession from Sierra Espuña-Mula basin (Betic Cordillera, S Spain). Eight microfacies (Mf1 to Mf8) have recognized, based mainly on fossil assemblages (principally larger benthic foraminifera), and rock texture fabric. The fossiliferous assemblage can be assigned ‘subtropical’ heterozoan association or low-latitude ‘foralgal facies’, which are dominated by non-framework building, light-dependent biota such as perforate foraminifera, coralline algae, sometimes green algae solitary corals. Larger foraminifer assemblages, corresponding euphotic oligophotic conditions large surface showed, suggest a progressive marine ramp under essentially oligotrophic conditions. Eventually, supply detrital sediments continent and/or upwelling currents increases nutrients waters. Comparison with other Tethyan sectors allows stating that coral-reef buildups (z-corals) were widespread shallow central eastern Ocean, but these neither great dimensions nor dominant because much more presence foraminifera. Moreover, coral constructions completely absents Tethys. dominance foraminifera absence z-corals explained particular paleogeographic features due occurrence narrow deep oceanic branch (i.e., Maghrebian Flysch Basin) connecting Atlantic Ocean. various issues regarding morphological characters area, sizes tests, specific diversity intraspecific variability, number appearances last occurrences during analyzed compared those appearing sectors. In addition, early late Bartonian boundary is area critical for biological change shallow-marine environments along margins.