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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
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İbrahim Uysal A. Dündar Şen E. Yalçın Ersoy Yildirim Dilek Samet Saka Federica Zaccarini Monica Escayola Orhan Karslı 《Mineralogy and Petrology》2014,108(1):49-69
We present the whole-rock and the mineral chemical data for upper mantle peridotites from the Harmanc?k region in NW Turkey and discuss their petrogenetic–tectonic origin. These peridotites are part of a Tethyan ophiolite belt occurring along the ?zmir-Ankara-Ercincan suture zone in northern Turkey, and include depleted lherzolites and refractory harzburgites. The Al2O3 contents in orthopyroxene and clinopyroxene from the depleted lherzolite are high, and the Cr-number in the coexisting spinel is low falling within the abyssal field. However, the orthopyroxene and clinopyroxene in the harzburgites have lower Al2O3 contents for a given Cr-number of spinel, and plot within the lower end of the abyssal field. The whole-rock geochemical and the mineral chemistry data imply that the Harmanc?k peridotites formed by different degrees of partial melting (~%10–27) of the mantle. The depleted lherzolite samples have higher MREE and HREE abundances than the harzburgitic peridotites, showing convex-downward patterns. These peridotites represent up to ~16 % melting residue that formed during the initial seafloor spreading stage of the Northern Neotethys. On the other hand, the more refractory harzburgites represent residues after ~4–11 % hydrous partial melting of the previously depleted MOR mantle, which was metasomatized by slab-derived fluids during the early stages of subduction. The Harmanc?k peridotites, hence, represent the fragments of upper mantle rocks that formed during different stages of the tectonic evolution of the Tethyan oceanic lithosphere in Northern Neotethys. We infer that the multi-stage melting history of the Harmanc?k peridotites reflect the geochemically heterogeneous character of the Tethyan oceanic lithosphere currently exposed along the ?zmir-Ankara-Erzincan suture zone. 相似文献
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LIU Fei YANG Jingsui Yildirim DILEK LIAN Dongyang XIE Yanxue NIU Xiaolu FENG Guangying ZHAO Hui HUANG Jian LI Guanlong 《《地质学报》英文版》2017,91(Z1):16-17
The ophiolites that crop out discontinuously along the~2000 km Yarlung Zangbo Suture zone(YZSZ)between the Nanga Parbat and Namche Barwa syntaxes in southern Tibet represent the remnants of Neotethyan oceanic lithosphere(Fig.1a).We have investigated the internal structure and the geochemical makeup of mafic-ultramafic rock assemblages that are exposed in the westernmost segment of the YZSZ where the suture zone architecture displays two distinct sub-belts of ophiolitic and mélange units separated by a continental Zhongba terrane(Fig.1b).These two sub-belts include the Daba–Xiugugabu in the south(Southern sub-belt,SSB)and the Dajiweng–Saga in the north(Northern sub-belt,NSB).We present new structural,geochemical,geochronological data from upper mantle peridotites and mafic dike intrusions occurring in these two sub-belts and discuss their tectonomagmatic origin.In-situ analysis of zircon grains obtained from mafic dikes within the Baer,Cuobuzha and Jianabeng massifs in the NSB,and within the Dongbo,Purang,Xiugugabu,Zhaga and Zhongba in the SSB have yielded crystallization ages ranging between130 and 122 Ma.Dike rocks in both sub-belts show N-MORB REE patterns and negative Nb,Ta and Ti anomalies,reminiscent of those documented from SSZ ophiolites.*Harzburgitic host rocks of the mafic dike intrusionsmainly display geochemical compositions of abyssal peridotites(Fig.2),with the exception of the Dajiweng harzburgites,which show the geochemical signatures of forearc peridotites(Lian et al.,2016).Extrusive rocks that are spatially associated with these peridotite massifs in both sub-belts also have varying compositional and geochemical features.Tithonian to Valanginian(150–135 Ma)basaltic rocks in the Dongbo massif have OIB-like geochemistry and 138 Ma basaltic lavas in the Purang massif have EMORB-like geochemistry(Liu et al.,2015).Tuffaceous rocks in the Dajiweng massif are140 Ma in age and show OIB-like geochemistry.We interpret these age and geochemical data to reflect a rifted continental margin origin of the extrusive rock units in both sub-belts.These data and structural observations show that the western Yarluang Zangbo ophiolites represent fragments of an Ocean-Continent Transition(OCT)peridotites altered by fluids in an initial supersubduction setting.We infer that mafic-ultramafic rock assemblages exposed in the SSB and NSB initially formed in an ocean–continent transition zone(OCTZ)during the late Jurassic,and that they were subsequently emplaced in the forearc setting of an intraoceanic subduction zone within a Neotethyan seaway during 130 to 122 Ma.The NSB and SSB are hence part of a single,S-directed nappe sheet derived from a Neotethyan seaway located north of the Zhongba terrane. 相似文献
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