The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Ayşegül Güney - One of the best experts on this subject based on the ideXlab platform.
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Late Cenozoic tectono-sedimentary evolution of the Ulukışla Basin: progressive basin development in south-central Turkey
International Journal of Earth Sciences, 2020Co-Authors: Esra Gürbüz, Gürol Seyitoğlu, Ayşegül GüneyAbstract:The Ulukışla Basin is one of the most important late Cretaceous-Cenozoic basins in central Anatolia. The basin is surrounded by the Bolkar Mountains of Tauride Platform in the south, the Niğde Massif of Central Anatolian Crystalline Complex to the north, and the Ecemiş Fault Zone and Aladağ Mountains in the east. The fact that time interval proposed for the formation of Ulukışla Basin is quite wide and more than one tectonic regime prevailed in the region, have led to various suggestions concerning the evolution of the basin. While the suggestions majorly examine the character of the basin during the late Cretaceous-early Cenozoic, the number of detailed studies on the status of the basin in the late Cenozoic is limited. In this study, we focused on the less-studied late Cenozoic evolution to differentiate the tectonic phases that controlled the development of Ulukışla Basin through structural data, and elaborate the responses of sedimentation and paleogeography during this period through detailed facies analyses. Our findings indicate that the Ulukışla Basin, which started to develop as a supradetachment basin in the late Cretaceous, has continued its extensional development progressively during its Cenozoic history. While the relatively well-studied early Cenozoic sequences represent a marine environment that was rapidly changed shallow- to deep-sea environment and then gained a shallow character by the middle Eocene, sedimentary features and fossil contents of the late Cenozoic units characterize deposition started in a paralic environment changing into a terrestrial environment rapidly, as a result of isolation by the uplifting of surrounding topographies while the basin continues its development under an extensional tectonic regime. However, the extensional basin history surceased in post-middle Eocene and post-middle Miocene, probably caused by the closing processes of the different branches of Neotethys Ocean.
Xinyuan Ji - One of the best experts on this subject based on the ideXlab platform.
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Cenozoic tectonic evolution of the bohai bay basin and its coupling relationship with pacific plate subduction
Journal of Asian Earth Sciences, 2016Co-Authors: Jintong Liang, Hongliang Wang, Xinyuan JiAbstract:Abstract The Bohai Bay Basin is a Mesozoic–Cenozoic rift basin in eastern China. Based mainly on a balanced-section analysis, this study compares the spatio-temporal differences of tectonic evolution in relation to strike-slip faults among different depressions within the basin. In combination with the analysis of subsidence characteristics, the study also attempts to clarify the Cenozoic tectonic evolution of the basin and its coupling relationship with the subduction of the Pacific Plate. It was found that: (1) the strike-slip faults were activated generally from south to north and from west to east during the Cenozoic; (2) there is a negative correlation between the intensity of tectonic activity in the Bohai Bay Basin and subduction rate of the Pacific Plate; and (3) the migration direction of the basin depocenters is consistent with the direction of Pacific Plate subduction.
Daniel P Schrag - One of the best experts on this subject based on the ideXlab platform.
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the mg isotopic composition of Cenozoic seawater evidence for a link between mg clays seawater mg ca and climate
Earth and Planetary Science Letters, 2015Co-Authors: John A Higgins, Daniel P SchragAbstract:Abstract Cooling of Earth's climate over the Cenozoic has been accompanied by large changes in the magnesium and calcium content of seawater whose origins remain enigmatic. The processes that control these changes affect the magnesium isotopic composition of seawater, rendering it a useful tool for elucidating the processes that control seawater chemistry on geologic timescales. Here we present a Cenozoic magnesium isotope record of carbonate sediments and use a numerical model of seawater chemistry and the carbon cycle to test hypotheses for the covariation between Cenozoic seawater chemistry and climate. Records are consistent with a 2–3× increase in seawater Mg/Ca and little change in the Mg isotopic composition of seawater. These observations are best explained by a change in the cycling of Mg-silicates. We propose that Mg/Ca changes were caused by a reduction in removal of Mg from seawater in low-temperature marine clays, though an increase in the weathering of Mg-silicates cannot be excluded. We attribute the reduction in the Mg sink in marine clays to changes in ocean temperature, directly linking the major element chemistry of seawater to global climate and providing a novel explanation for the covariation of seawater Mg/Ca and climate over the Cenozoic.
Austin J W Hendy - One of the best experts on this subject based on the ideXlab platform.
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the influence of lithification on Cenozoic marine biodiversity trends
Paleobiology, 2009Co-Authors: Austin J W HendyAbstract:Recent research has corroborated the long-held view that the diversity of genera within benthic marine communities has increased from the Paleozoic to the Cenozoic as much as three-to fourfold, after mitigating for such biasing influences as secular variation in time-averaging and environmental coverage. However, these efforts have not accounted for the considerable increase in the availability of unlithified fossiliferous sediments in strata of late Mesozoic and Cenozoic age. Analyses presented here on the Cenozoic fossil record of New Zealand demonstrate that unlithified sediments not only increase the amount of fossil material and hence the observed diversity therein, but they also preserve a pool of taxa that is compositionally distinct from lithified sediments. The implication is that a large component of the difference in estimates of within-community diversity between Paleozoic and Cenozoic assemblages may relate to the increased availability of unlithified sediments in the Cenozoic.
Craig J. R. Hart - One of the best experts on this subject based on the ideXlab platform.
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Petrogenetic and tectonic controls on magma fertility and the formation of post-subduction porphyry and epithermal mineralization along the late Cenozoic Anatolian Metallogenic Trend, Turkey
Mineralium Deposita, 2020Co-Authors: Fabien Rabayrol, Craig J. R. HartAbstract:The late Cenozoic Anatolian Metallogenic Trend in Turkey is a manifestation of westerly Aegean subduction and easterly Arabian continental collision along the Western Tethyan Orogenic Belt. The 1500 × 200 km late Cenozoic Anatolian magmatism hosts many gold-rich porphyry and epithermal deposits and prospects (~ 27 Moz Au) that formed during the tearing of the Aegean slab and Arabian slab break-off events that initiated at 15 Ma in western Anatolia and 25 Ma in eastern Anatolia. Although the temporal and spatial correlations between slab segmentation, late Cenozoic magmatism, and associated gold-rich porphyry and epithermal mineralization has been intuitively proposed, the genetic relationships between asthenospheric upwelling, subcontinental lithospheric mantle instability, and magma fertility have not been well established. Herein, new geochemical and radiogenic Sr, Nd, and Pb isotope data from Miocene to Pliocene magmatic rocks that are genetically related to porphyry, epithermal, and skarn systems from western, central, and eastern Anatolia are presented and interpreted with previously published geochemical data from late Cenozoic intrusion-related mineral systems throughout Anatolia. The magma fertility of the late Cenozoic post-subduction igneous suites along the late Cenozoic Anatolian Metallogenic Trend is assessed and is best indicated by the SiO_2 (61.8 ± 5.5 wt%) content, Sr/Y (> 20) and Ba/Ta ratios (> 428), and (ε_Nd)_i values (
