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 fi rst-order constraint on possible mechanisms of regional uplift. Nannofossil, ostracod, and planktic foraminifera biostratigraphy of the Başyayla 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 identifi cation 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 fi ltered with a 100-km-wide smoothing window. Uplift along the southern margin of the Central Anatolian Plateau is also refl ected 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. their employment. Individual scientists are hereby granted permission, without fees or furtherCopyright not claimed on content prepared wholly by U.S. government employees within scope of Notes
""\\"According to the literature, the Adana Basin, at the easternmost part of the Mediterranean. Basin in southern Turkey, records the Pliocene stage with shallow-marine to fluvial deposits.. Our micropalaeontological analysis of samples from the Adana Basin reveal Late Lago–Mare. biofacies with Paratethyan ostracod assemblages pertaining to the Loxocorniculina djafarovi. zone. Grey clays rich in planktonic foraminifera lie above the Lago–Mare deposits. Within the. grey clays, the continuous occurrence of the calcareous nannofossil Reticulofenestra zancleana. and the base of the Reticulofenestra pseudoumbilicus paracme points to an Early Zanclean age. (5.332–5.199 Ma). Both ostracod and benthic foraminifera indicate epibathyal and bathyal. environments. 87Sr\\\\\\\/86Sr measurements on planktonic and benthic foraminifera fall below the. mean global ocean value for the Early Zanclean, indicating potentially insufficient mixing of. low 87Sr\\\\\\\/86Sr Mediterranean brackish ‘Lago–Mare’ water with the global ocean in the earliest. Pliocene. We utilize the ages and palaeodepths of the marine sediments together with their modern. elevations to determine uplift rates of the Adana Basin of 0.06 to 0.13 mm a21 since 5.2–5.3 Ma. (total uplift of 350–650 m) from surface data, and 0.02–0.13 mm a21 since c. 1.8 Ma (total uplift. of 30–230 m) from subsurface data.. Supplementary material: Microphotographs of foraminifers, ostracods, and calcareous nannofossils,. plots of the calcareous nannofossil frequencies, occurrence of foraminifers and ostracods in. the study sections, results of Sr isotopic analysis, and a complete list of fossils are available at. www.geolsoc.org.uk\\\\\\\/SUP18535.\\""
At the southern margin of the Central Anatolian Plateau (CAP), marine deposits that overlie the Central Tauride units at up to 2 km of elevation were used to constrain the onset of uplift to the middle‐late Miocene. This study demonstrates that much younger marine deposits cap the southern margin. We recognize the Last Common Occurrence of Neogloboquadrina spp. (sin) (0.61 Ma) and Pseudoemiliania lacunosa (0.467 Ma), which points to an early middle Pleistocene age. The benthic fauna indicates an epibathyal marine environment (400 to 500 m paleodepth), with an associated paleocoastline now at ~1,500 to 1,600 m above sea level. Our new results imply uplift rates of up to 3.21–3.42 mm/yr for the CAP southern margin since the deposition of the young marine units. In the area, the evaluation of late Pleistocene and Holocene uplift rates of ~1 mm/yr points to a post early middle Pleistocene short‐lived period of rapid uplift of the CAP southern margin, which can correlate the short‐lived surface uplift signal in numerical models of slab breakoff. Overall, this work demonstrates that the majority of the modern topography at the CAP southern margin (1,500 to 1,600 m) was only recently acquired, pointing to the absence of a significant orographic barrier along the southern plateau margin prior to 500 ka. The multiphased uplift recognized at the CAP southern margin by previous authors, as well as the fast uplift rate documented in this work, can be linked to lithosphere delamination and subsequent slab breakoff during the Arabian‐Anatolian continental collision.
We used two sediment cores from the ancient harbour of Rome (Italy) for palaeoenvironmental reconstruction. The imperial harbour of Rome and its town, Portus, were constructed in the Tiber Delta area. Today, they are similar to 3 km from the coast, close to Leonardo da Vinci International Airport. The port was excavated during the reign of Emperor Claudius, inaugurated by Nero in 64 AD, and substantially enlarged under Emperor Trajan. This paper focuses on analyses of ostracods in sediment cores from the harbour and provides insights into the palaeoenvironmental evolution of the harbour water bodies. Pollen data complement this ostracod-based reconstruction, providing information about the vegetation around the port. One core (PTS13) was taken from the dock area (darsena) excavated at the time of Claudius. The second core (PTS5) was collected from the Trasverso Channel (Canale Trasverso), excavated after the port inauguration and later dredged during the fourth century AD because it had filled in with silt. Radiocarbon, archaeological and pollen data indicate the two cores overlap in time slightly, or perhaps not at all, the core from the dock site (PTS13) containing the older record. Ostracods recovered from the two sites represent very different aquatic environments, driven in one case by the Tiber River input and in the other by "marine" harbour waters. Parallel study of ostracods and pollen in the cores reveals the impact of harbour management activities, which are linked to ship hull maintenance, as well as erosion and siltation in this coastal setting
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