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31.
Timur Hammond 《Urban geography》2013,34(7):1039-1054
Istanbul’s Taksim Square has long been a place from which people have envisioned the city and the nation. As such, it has a long history of architectural interventions. This essay describes three new interventions as they appeared in July2018, two years after the failed coup attempt of 15July2016: a municipal complex commemorating the resistance to the coup attempt; the juxtaposition of a memorial photo exhibit and the void of the Atatürk Culture Center; and the rapid construction of the Taksim Mosque. Drawing on conceptualizations of landscape and scholarship on Taksim Square’s contested meanings, this paper utilizes the “politics of perspective” as an analytical lens to examine how authorities are attempting to create anew way of seeing in the city. I argue that this project has acquired a new character in the aftermath of the coup attempt, placing viewers within the landscape rather than outside it. 相似文献
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Morpho-tectonic evolution of the Marmara Sea inferred from multi-beam bathymetric and seismic data 总被引：1，自引：6，他引：1
Erkan?Goka?anEmail author Timur?Usta?mer Cem?Gazio?lu Zeki?Ya?ar?Yucel Kurultay??ztürk Hüseyin?Tur Berkan?Ecevito?lu Bu?ser?Tok 《Geo-Marine Letters》2003,23(1):19-33
In an initial stage, the Sea of Marmara developed as a graben and, in due course, considerable volumes of sediments were deposited in this basin. Before 200 ka, a new fault (New Marmara Fault) cutting through the whole basin developed, which postdated large sub-marine land sliding in the western part of the basin. This mass movement created the Western Ridge. The initiation of this strike-slip fault indicates that the extensional stress regime was replaced by a new, shearing stress field. In the eastern part of the Marmara Basin, the New Marmara Fault consists of two branches. The northern one replaces the normal faulting at the bottom of the northeastern slope of the basin. As a result, this slope has been rejuvenated. The southern branch is located along the central axis of the basin, forming the major extension of the North Anatolian Fault Zone within the region. Two restraining bends were formed because of the counterclockwise rotation of that part of the Anatolian Block. This resulted the uplifting of the Eastern Ridge and the formation of the positive flower structure within the Tekirdag Basin. The establishment of the compressional regime around the Sea of Marmara also resulted in the northwest–southeast shortening of the initial Marmara Basin. 相似文献
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The numerical and proportional distributions of benthic macroinvertebrates in Tunca (Tundja, Tundzha) River (Edirne/Turkey) were determined from July 2002 to June 2003 at monthly intervals at four different stations. It was found that the benthic macrofauna consisted of 63% Oligochaeta, 24% Chironomidae larvae, and 13% Varia by numbers. According to the Shannon‐Wiener index, Tunca River had a diversity of 1.36; station 2 and September were found to have the highest diversity while station 4 and December to have the poorest. According to Bray‐Curtis similarity index, stations 2 and 3 and April and May were found to be the most similar to each other while stations 1 and 4 and August and January were found to be the most different from each other for the dynamics of the benthic macrofauna. Also some physicochemical parameters of the water (water temperature, electrical conductivity, pH, dissolved oxygen, chloride, total hardness, NO3–‐N, NO2–‐N, sulfate, phosphate, biochemical and chemical oxygen demands) were analyzed. Pearson correlation index supported the relationships between the dynamics of organisms and physicochemical variables. The relation between the number of macroinvertebrates and pH (r = +0.57, P < 0.05) was direct proportional while the relation between the number of macroinvertebrates and NO3–‐N (r = –0.99, P < 0.05) was inverse proportional. Furthermore, the Chironomidae larvae of Bryophaenocladius muscicola and Mesosmittia flexuella were new records for Turkish Thrace region. High pH and supersaturated oxygen levels, hard water quality, second quality levels of NO3–‐N, BOD, COD and fourth quality levels of NO2–‐N as well as the density of 490 individuals m–2 for 124 taxa and the diversity of 1.36 showed that similar studies should be repeated periodically in Tunca to determine the future of the river. 相似文献
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We have studied seismic surface waves of 255 shallow regional earthquakes recently recorded at GEOFON station ISP (Isparta, Turkey) and have selected these 52 recordings with high signal-to-noise ratio for further analysis. An attempt was made by the simultaneous use of the Rayleigh and Love surface wave data to interpret the planar crust and uppermost mantle velocity structure beneath the Anatolian plate using a differential least-square inversion technique. The shear-wave velocities near the surface show a gradational change from approximately 2.2 to 3.6 km s− 1 in the depth range 0–10 km. The mid-crustal depth range indicating a weakly developed low velocity zone has shear-wave velocities around 3.55 km s− 1. The Moho discontinuity characterizing the crust–mantle velocity transition appears somewhat gradual between the depth range 25–45 km. The surface waves approaching from the northern Anatolia are estimated to travel a crustal thickness of 33 km whilst those from the southwestern Anatolia and part of east Mediterranean Sea indicate a thicker crust at 37 km. The eastern Anatolia events traveled even thicker crust at 41 km. A low sub-Moho velocity is estimated at 4.27 km s− 1, although consistent with other similar studies in the region. The current velocities are considerably slower than indicated by the Preliminary Reference Earth Model (PREM) in almost all depth ranges. 相似文献
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The combined RUSLE/SDR approach integrated with GIS and geostatistics to estimate annual sediment flux rates in the semi-arid catchment,Turkey 总被引：1，自引：0，他引：1
Selen Deviren Saygın Ali Ugur Ozcan Mustafa Basaran Ozgur Burhan Timur Melda Dolarslan Fevziye Ebru Yılman Gunay Erpul 《Environmental Earth Sciences》2014,71(4):1605-1618
Quantitative evaluation of the spatial distribution of the erosion risk in any watershed or ecosystem is one of the most important tools for environmentalists, conservationists and engineers to plan natural resource management for the sustainable environment in a long term. This study was performed in the semi-arid catchment of the Saraykoy II Irrigation Dam, Cankiri, located in the transition zone between the Central Anatolia Steppe and the Black Sea Forests of Turkey. The total area of the catchment is 262.31 ha. The principal objectives were to quantify both potential and actual soil erosion risks by the Revised Universal Soil Loss Equation (RUSLE) and to estimate the amount of sediments to be delivered from the hillslope of the catchment to the reservoir of the dam using the sediment delivery ratio (SDR) in combination with the RUSLE model. All factor and sub-factor calculations required for solving the RUSLE model and SDR in the catchment were made spatially using DEM, GIS and Geostatistics. As the main catchment was divided into twenty-five sub-catchments, the predicted actual soil loss (by the model) was 146,657.52 m3 year?1 and the weighted average of SDR estimated by areal distribution (%) of the sub-watersheds was 0.344 for whole catchment, resulted in 50,450.19 m3 year?1 sediment arriving to the reservoir. Since the Dam has a total storage capacity of 509 × 103 m3, the life expectancy of the Dam is estimated as 10.09 year. This estimation indicated that the dam has a relatively short economic life and there is a need for water-catchment management and soil conservation measures to reduce erosion. 相似文献
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P. Ayda Ustaömer 《International Journal of Earth Sciences》1999,88(1):2-12
The West Pontides tectonic belt of northern Turkey comprises a Lower Ordovician–Lower Carboniferous transgressive sequence. A stratigraphic basement to this Paleozoic sequence is exposed in the Bolu area. The tectono-stratigraphy of the basement closely resemble that of the Cadomian belt of western Europe. Three rock units forming the basement imply development of an Andean-type active continental margin during the pre-Early Ordovician period. High-grade metamorphics (the Sünnice Group), granitoids (the Bolu Granitoid Complex) and evolved felsic meta-volcanic rocks (the Ça?urtepe Formation) are exposed unconformably beneath the Lower Ordovician fluvial clastics, between the Bolu-Yedigöller area, to the north of Bolu. The Bolu Granitoid Complex comprises a group of intrusive rocks of variable composition and size, generated through multiple episodes of magmatism, and is represented by two separate intrusive bodies within the study area, the Tüllükiri? Pluton in the west and the Kap?kaya Pluton in the east. Both plutons are mainly tonalite and granodiorite in composition. More felsic and mafic compositional varieties also occur. Major and trace element chemical characteristics of the granitoids, as well as biotite chemistry, indicate that these are volcanic arc-type granitoids and are products of an immature arc developed during early stages of a subduction. Furthermore, textural and chemical characteristics of the plutons show that these are subvolcanic intrusions, emplaced at shallow depths, and are calc-alkaline in composition. The granitoidic plutons intrude the Ça?urtepe Formation. The Ça?urtepe Formation is represented by arc-type volcanics and volcaniclastics. Both the Ça?urtepe Formation and the granitoids represent subduction-zone magmatism constructed on a continental crust, represented by the Sünnice Group. The history is very similar to Cadomian active margins as exposed in western Europe (i.e., the North Armorican and Bohemia massifs) and therefore the basement to the Paleozoic of the West Pontides is considered to be a preserved remnant of the Cadomian belt. 相似文献
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Erkan Gökaşan Mustafa Ergin Mustafa Özyalvaç Halil İbrahim Sur Hüseyin Tur Tolga Görüm Timur Ustaömer Fatma Gül Batuk Hakan Alp Halim Birkan Ahmet Türker Erhan Gezgin Murat Özturan 《Geo-Marine Letters》2008,28(2):107-129
Seismic profiling, bathymetric and physical oceanographic data collected from the Çanakkale Strait revealed that the morphological evolution of the strait has been controlled by tectonic activity, and sediment erosion and deposition. Sediments in the strait have been sourced mostly by rivers draining the Biga Peninsula during lowstand periods. In highstand periods, by contrast, deposits in the strait were reworked by currents. The seafloor morphology of the Çanakkale Strait is also controlled by a sequence of factors ranging from tectonics to current erosion and deposition. Channel deposits overlying the basement are being eroded at the narrower, meandering central section of the strait (the Nara Passage) due to high current velocities. The eroded sediments are deposited in the relatively linear and wider, northern and southern sectors of the strait exposed to low current velocities. As a result, the high-energy areas are more deeply incised due to the erosion, whereas deposition elevates the seafloor in the areas exposed to lower current energy. Three strike-slip faults, which possibly relate to the activity of the North Anatolian Fault Zone, are responsible for the irregular shape of the strait and this, in turn, controls the current velocity along the strait. The high-energy conditions probably commenced with the latest invasion of Mediterranean waters some 12 ka b.p., and have continued as a two-layered current system to the present day. 相似文献
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Faulting, mass-wasting and deposition in an active dextral shear zone, the Gulf of Saros and the NE Aegean Sea, NW Turkey 总被引：1，自引：1，他引：0
Timur Ustaömer Erkan Gökaşan Hüseyin Tur Tolga Görüm Fatma Gül Batuk Doğan Kalafat Hakan Alp Berkan Ecevitoğlu Halim Birkan 《Geo-Marine Letters》2008,28(3):171-193
Structural, mass-wasting and sedimentation processes along an active dextral shear zone beneath the Gulf of Saros and the
NE Aegean Sea were investigated on the basis of new high-resolution swath bathymetric data and multi-channel seismics. A long
history of dextral shearing operating since the Pliocene culminated in the formation of a NE-SW-trending, ca. 800-m-deep basin
(the so-called inner basin) in this region, which is bordered by a broad shelf along its northern and eastern sides and a
narrow shelf at the southern side. The western extension of the North Anatolian Fault Zone (the Ganos Fault) cuts the eastern
shelf along a narrow deformation zone, and ends sharply at the toe of the slope, where the strain is taken up by two NE-SW-oriented
fault zones. These two fault zones cut the basin floor along its central axis and generate a new, Riedel-type pull-apart basin
(the so-called inner depression). According to the bathymetric and seismic data, these basin boundary fault zones are very
recent features. The northern boundary of the inner depression is a through-going fault comprising several NE-SW- and E-W-oriented,
overlapping fault segments. The southern boundary fault zone, on the other hand, consists of spectacular en-echelon fault
systems aligned in NE–SW and WNW–ESE directions. These en-echelon faults accommodate both dextral and vertical motions, thereby
generating block rotations along their horizontal axis. As the basin margins retreat, the basin widens continuously by mass-wasting
of the slopes of the inner basin. The mass-wasting, triggered by active tectonics, occurs by intense landsliding and channel
erosion. The eroded material is transported into the deep basin, where it is deposited in a series of deep-sea fans and slumps.
The high sedimentation rate is reflected in an over 1,500-m-thick basin fill which has accumulated in Pliocene–Quaternary
times. 相似文献