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We present detailed Messinian paleoenvironmental reconstructions for the Adana Basin based on a multidisciplinary approach that utilizes the fossil content of the Kuzgun and Handere Formations. To reconstruct the paleoenvironmental changes that affected the Adana Basin during the Messinian, we analyzed mollusk, ostracod, planktonic and benthonic foraminifer, and calcareous nannofossil assemblages from 2 stratigraphic sections near Kabasakal village (Adana, southern Turkey). To determine if the environmental changes recognized in the Adana Basin are local or regional, and to understand the extent to which the global changes in oceanic circulation impacted the Mediterranean sedimentary basins, we compare our results with Messinian sections from other locations in the Mediterranean region (northern Italy, southern Italy, Cyprus, Algeria, and southern Turkey). The occurrence of N. humerosa, G. bulloides, G. woodi, N. acostaensis, N. atlantica (planktonic forams), S. multiflora, T. rugosa, P. elongata, C. scitula, L. lipadusensis (ostracods), R. rotaria, A. primus, and A. delicatus (calcareous nannofossils) allows us to constrain the uppermost part of the Kuzgun Formation to the early Messinian. The ostracod assemblages indicate an enclosed marine environment characterized by sporadic local freshwater inputs that decreased the salinity of the basin. In contrast, in the late Messinian Handere Formation, the presence of Paratethyan ostracods pertaining to the Loxoconcha mülleri zone and to the Loxocorniculina djafarovi zone in the Handere Formation indicates the occurrence of the Messinian brackish water Lago-Mare event in the Adana Basin, which occurred throughout the Mediterranean between 5.60 and 5.33 Ma. [ABSTRACT FROM AUTHOR]

The timing and pattern of surface uplift of Miocene marine sediments capping the southern margin of the Central Anatolian Plateau in southern Turkey provide a first-order constraint on possible mechanisms of regional uplift. Nannofossil, ostracod, and planktic foraminifera biostratigraphy of the Basyayla section (Mut-Ermenek Basin) within the Mut and Köselerli Formations suggests a Tortonian age for marine sediments unconformably capping basement rocks at ~2 km elevation. The identification of biozone MMi 12a (7.81-8.35 Ma) from planktic foraminifera in the upper part of the section provides the tightest constraint on the age, which is further limited to 8.35-8.108 Ma as a result of the reverse polarity of the collected samples (chron 4r.1r or 4r.2r). This provides a limiting age for the onset of surface uplift at the margin of one of the world's major orogenic plateaus, from which an average uplift rate of 0.24-0.25 mm/yr can be calculated. Subhorizontal beds of the uppermost marine sediments exposed throughout the Mut-Ermenek Basin suggest minimal localized deformation, with just minor faulting at the basin margin and broad antiformal deformation across the basin. This implies that the post--8 Ma uplift mechanism must be rooted deep within the crust or in the upper mantle. Published Pn-wave velocity data for the region are compatible with topography compensated by asthenosphere across the southern margin of the plateau, showing a close match to the highest topography when elevations are filtered with a 100-km-wide smoothing window. Uplift along the southern margin of the Central Anatolian Plateau is also reflected by the pattern of Miocene marine sediments capping the margin, which form an asymmetric drape fold over the topography. These observations, together with tomographic evidence for slab steepening and break-off beneath the Eastern Anatolian Plateau, suggest that at least some of the ~2 km of post-8 Ma uplift of the southern Central Anatolian Plateau margin is compensated by low-density asthenospheric mantle that upwelled following slab break-off. [ABSTRACT FROM AUTHOR]