TY - JOUR A1 - Schildgen, Taylor F. A1 - Cosentino, D. A1 - Caruso, A. A1 - Buchwaldt, Robert A1 - Yildirim, C. A1 - Bowring, S. A. A1 - Rojay, B. A1 - Echtler, Helmut Peter A1 - Strecker, Manfred T1 - Surface expression of eastern Mediterranean slab dynamics: Neogene topographic and structural evolution of the southwest margin of the Central Anatolian Plateau, Turkey JF - TECTONICS N2 - The southwest margin of the Central Anatolian Plateau has experienced multiple phases of topographic growth, including the formation of localized highs prior to the Late Miocene that were later affected by wholesale uplift of the plateau margin. Our new biostratigraphic data limit the age of uplifted marine sediments at the southwest plateau margin at 1.5 km elevation to <7.17 Ma, and regional lithostratigraphic correlations imply that the age is <6.7 Ma. Single-grain CA-TIMS U-Pb zircon analyses from a reworked ash within the marine sediments yield dates as young as 10.6 Ma, indicating a maximum age that is consistent with the biostratigraphy. Our structural measurements within the uplifted region and fault inversion modeling agree with previous findings in surrounding regions, with early contraction followed by strike-slip and extensional deformation during uplift. Focal mechanisms from shallow earthquakes show that the extensional phase has continued to the present. Broad similarities in the change in the tectonic stress regime (after 8 Ma) and the onset of surface uplift (after 7 Ma) imply that deep-seated process(es) caused post-7 Ma uplift. The geometry of lithospheric slabs beneath the plateau margin, Pliocene to recent alkaline volcanism, and the uplift pattern with accompanying normal faulting point toward slab tearing and localized heating at the base of the lithosphere as a probable mechanism for post-7 Ma uplift of the southwest margin. Considering previous work in the region, there appears to be an important link between slab dynamics and surface uplift throughout the Anatolian Plateau’s southern margin. Y1 - 2012 U6 - https://doi.org/10.1029/2011TC003021 SN - 0278-7407 SN - 1944-9194 VL - 31 PB - AMER GEOPHYSICAL UNION CY - WASHINGTON ER - TY - JOUR A1 - Schildgen, Taylor F. A1 - Cosentino, D. A1 - Frijia, Gianluca A1 - Castorina, F. A1 - Dudas, F. Oe. A1 - Iadanza, A. A1 - Sampalmieri, G. A1 - Cipollari, Paola A1 - Caruso, A. A1 - Bowring, S. A. A1 - Strecker, Manfred T1 - Sea level and climate forcing of the Sr isotope composition of late Miocene Mediterranean marine basins JF - Geochemistry, geophysics, geosystems N2 - Sr isotope records from marginal marine basins track the mixing between seawater and local continental runoff, potentially recording the effects of sea level, tectonic, and climate forcing in marine fossils and sediments. Our 110 new Sr-87/Sr-86 analyses on oyster and foraminifera samples from six late Miocene stratigraphic sections in southern Turkey, Crete, and Sicily show that Sr-87/Sr-86 fell below global seawater values in the basins several million years before the Messinian Salinity Crisis, coinciding with tectonic uplift and basin shallowing. 87Sr/86Sr from more centrally located basins (away from the Mediterranean coast) drop below global seawater values only during the Messinian Salinity Crisis. In addition to this general trend, 55 new Sr-87/Sr-86 analyses from the astronomically tuned Lower Evaporites in the central Apennines (Italy) allow us to explore the effect of glacio-eustatic sea level and precipitation changes on Sr-87/Sr-86. Most variation in our data can be explained by changes in sea level, with greatest negative excursions from global seawater values occurring during relative sea level lowstands, which generally coincided with arid conditions in the Mediterranean realm. We suggest that this greater sensitivity to lowered sea level compared with higher runoff could relate to the inverse relationship between Sr concentration and river discharge. Variations in the residence time of groundwater within the karst terrain of the circum-Mediterranean region during arid and wet phases may help to explain the single (robust) occurrence of a negative excursion during a sea level highstand, but this explanation remains speculative without more detailed paleoclimatic data for the region. Y1 - 2014 U6 - https://doi.org/10.1002/2014GC005332 SN - 1525-2027 VL - 15 IS - 7 SP - 2964 EP - 2983 PB - American Geophysical Union CY - Washington ER -