Tectonic and sea level controls on the back-stepping early miocene carbonate platforms: Adana Basin, Turkey

The Karaisali complex exposes Miocene carbonate platforms that developed on a tectonically controlled, rugged antecedent topography during an ice-house system. The factors affecting platform initiation, architecture, facies distribution, and eventually drowning of those Miocene platforms remain poorly understood because of the stratigraphic and structural complexities of the Adana Basin. In this work, sedimentological and structural analysis supplemented by dating using strontium isotope lead to a better understanding of platform developing in a strongly subsiding basin. Using twenty one measured sections, ultra-high resolution photopans, petrographic, and strontium isotope analysis; an interpreted depositional model and detailed cross section were built. The architecture of the platforms can be divided into two transgressive and two highstand systems tracts separated by a maximum flooding surface. This work shows that the small attached carbonate platforms of the Karaisali Formation colonized a steep-rugged basement topography in a rapidly subsiding basin without any significant syn-sedimentary movement. The combination of rapid subsidence with a subsidence rate of more than 400 m/MA and eustacy drove the carbonate platform to successively nucleate, aggrade with minor progradation, and eventually drown on basement highs. The relative sea level rise resulted in back-stepping of the carbonate platforms towards landwards and development of Early Burdigalian to Late Serravalian reefal carbonates on the paleo-highs of the antecedent topography further in northernwest.