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Aksu Hakan Cetin Mahmut Aksoy Hafzullah Yaldiz Sait Genar Yildirim Isilsu Keklik Gulsah 《Natural Hazards》2022,111(3):2379-2405
Natural Hazards - This study characterises the spatial and temporal behaviours of maximum precipitation over the Black Sea Region in northern Turkey. Maximum precipitation data of 14 standard... 相似文献
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Andrea Festa Kei Ogata Gian Andrea Pini Yildirim Dilek Giulia Codegone 《International Geology Review》2015,57(5-8):540-562
In the Northern Apennines of Italy, mud-rich olistostromes (sedimentary mélanges) occur at different stratigraphic levels within the late Oligocene–early Miocene sedimentary record of episutural/wedge-top basins. They are widely distributed along the exhumed outer part of the Ligurian accretionary complex, atop the outer Apenninic prowedge, over an area about 300 km long and 10–15 km wide. Olistostromes represent excellent examples of ancient submarine mass-transport complexes (MTCs), consisting of stacked cohesive debris flows that can be directly compared to some of those observed in modern accretionary wedges. We describe the internal arrangement of olistostrome occurrences in the sector between Voghera and the Monferrato area, analysing their relationships with mesoscale liquefaction features, which are commonly difficult to observe in modern MTCs. Slope failures occurred in isolated sectors along the wedge front, where out-of-sequence thrusting, seismicity, and different pulses of overpressured tectonically induced fluid flows acted concomitantly. Referring to the Northern Apennines regional geology, we also point out a gradual lateral rejuvenation (from late Oligocene to early Miocene) toward the SE and an increasing size and thickness of the olistostromes along the strike of the frontal Apenninic prowedge. This suggests that morphological reshaping of the outer prowedge via mass-transport processes balanced, with different pulses over a short time span, the southeastward migration and segmentation of accretionary processes. The latter were probably favoured by the occurrence in the northwestern part of the Northern Apennines of major, inherited palaeogeographic features controlling the northward propagation of the prowedge. Detailed knowledge of olistostromes, as ancient examples of MTCs related to syn-sedimentary tectonics and shale diapirism, and of their lateral variations in term of age and size, provides useful information in regard to better understanding of both the tectono-stratigraphic evolution of the Apenninic prowedge and the submarine slope failures in modern accretionary wedges. 相似文献
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Xiangzhen XU Pierre CARTIGNY Jingsui YANG Yildirim DILEK Fahui XIONG Guolin GUO 《《地质学报》英文版》2019,93(Z2):38-38
We report new δ13C ‐values data and N‐content and N‐aggregation state values for microdiamonds recovered from peridotites and chromitites of the Luobusa ophiolite (Tibet) and chromitites of the Ray‐Iz ophiolite in the Polar Urals (Russia). All analyzed microdiamonds contain significant nitrogen contents (from 108 up to 589 ± 20% atomic ppm) with a consistently low aggregation state, show identical IR spectra dominated by strong absorption between 1130 cm?1 and 1344 cm?1, and hence characterize Type Ib diamond. Microdiamonds from the Luobusa peridotites have δ13C ‐PDB‐values ranging from ‐28.7‰ to ‐16.9‰, and N‐contents from 151 to 589 atomic ppm. The δ13C and N‐content values for diamonds from the Luobusa chromitites are ‐29‰ to ‐15.5‰ and 152 to 428 atomic ppm, respectively. Microdiamonds from the Ray‐Iz chromitites show values varying from ‐27.6 ‰ to ‐21.6 ‰ in δ13C and from 108 to 499 atomic ppm in N. The carbon isotopes values bear similar features with previously analyzed metamorphic diamonds from other worldwide localities, but the samples are characterized by lower N‐contents. In every respect, they are different from diamonds occurring in kimberlites and impact craters. Our samples also differ from the few synthetic diamonds; we also analyzed showing enhanced δ13C ‐variability and less advanced aggregation state than synthetic diamonds. Our newly obtained N‐aggregation state and N‐content data are consistent with diamond formation over a narrow and rather cold temperature range (i.e. <950°C), and in a short residence time (i.e. within several million years) at high temperatures in the deep mantle. 相似文献
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M. Alkan M. Oruc Y. Yildirim D. Z. Seker K. Jacobsen 《Journal of the Indian Society of Remote Sensing》2013,41(3):587-596
Rapid land use/land cover changes have taken place in many cities of Turkey. Land use and land cover changes are essential for wide range of applications. In this study, Landsat TM satellite imageries date from 1987, 1993, 2000 and 2010 were used to analyse temporal and spatial changes in the Western Black Sea Region of Turkey. Zonguldak and Eregli two largest and economic important cities which have been active coal mining and iron fabric areas. Maximum Likelihood Classification technique was implemented and the results were represented in classes of open area, forest, agricultural, water, mining, urban and pollution in the sea. Urban areas on both cities increased from 1987 to 2010. The agricultural and open areas from 1987 to 2010 decreased in parallel to land use and land cover change in both cities. Meanwhile, forest areas increased continuously with about 20 % from 1987 to 2010 in both cities. As industrial activity, the coal fields doubled from 1987 to 2010. 相似文献
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<正>The IGCP 649 project entitled "Diamonds and Recycled Mantle"was approved by UNESCO and IUGS in March 2015.This project is led by an international team of researchers,including Prof.Yang Jingsui of Institute of Geology of CAGS(China),Prof.Yildirim Dilek of Miami 相似文献
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Yildirim DILEK 《《地质学报》英文版》2015,89(Z2):6-6
<正>The internal structure-stratigraphy and geochemical signatures of most forearc-suprasubduction zone ophiolites display structural,petrological,geochemical and geochronological evidence,recording different stages of subduction initiation-related magmatism,material flux,metasomatism and deformation.There is a well-developed 相似文献
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XIONG Fahui YANG Jingsui ROBINSON Paul T. DILEK Yildirim MILUSHI Ibrahim XU Xiangzhen ZHANG Zhongming ZHOU Wen CHEN Yanhong HUANG Zhu LAIShengming ZHANG Lan 《《地质学报》英文版》2015,89(Z2):98-98
<正>The ultramafic massif of Bulqiza,which belongs to the eastern ophiolitic belt of Albania,is a major source of metallurgical chromitite ore.The massif consists of a thick(4 km)sequence,composed from the base upward of tectonized harzburgite with minor dunite,a transitional zone of dunite,and a magmatic sequence of wehrlite, 相似文献