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Ömer Emre Tamer Y. Duman Selim Özalp Fuat Şaroğlu Şeyda Olgun Hasan Elmacı Tolga Çan 《Bulletin of Earthquake Engineering》2018,16(8):3229-3275
We have updated the active fault map of Turkey and built its database within GIS environment. In the study, four distinct active fault types, classified according to geochronological criteria and character, were delineated on the 1:25,000 base map of Turkey. 176 fault segments not included in the former active fault map of Turkey, have been identified and documented. We infer that there are 485 single fault segments which are substantially potential seismic sources. In total 1964 active-fault base-maps were transferred into the GIS environment. Each fault was attributed with key parameters such as class, activity, type, length, trend, and attitude of fault plane. The fault parameters are also supported by slip-rate and seismogenic depth inferred from available GPS, seismological and paleoseismological data. Additionally, expected maximum magnitude for each fault segment was estimated by empirical equations. We present the database in a parametric catalogue of fault segments to be of interest in earthquake engineering and seismotectonics. The study provides essential geological and seismological inputs for regional seismic hazard analysis of all over Turkey and its vicinity. 相似文献
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J.Obiukwu Duru 《Journal of Hydrology》1984,70(1-4):71-83
An evapotranspiration model which parallels that proposed earlier by Blaney and Morin has been developed for application in Nigeria. The model, designated as the Blaney-Morin-Nigeria evapotranspiration model, predicts potential evapotranspiration with accuracy and consistency that are better than the Penman model, under Nigerian conditions. It is suggested that the Blaney-Morin evapotranspiration concept may have similar potential elsewhere when given specific form with appropriate constants derived to reflect climatic peculiarities. 相似文献
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Coal and gas outburst hazard in Zonguldak Coal Basin of Turkey,and association with geological parameters 总被引：1，自引：0，他引：1
Coal and gas outbursts have been a major geological hazard to underground coal mining for over 150 years and continue to cause serious problems in all over the world. In order to have a better understanding of the phenomenon, it is worthwhile making a historical review of the occurrences and a combat of the events. Many investigations and researches have been done to characterize and prevent the outburst occurrences in the worldwide, but there has been no detailed investigation about coal and gas outburst occurrences in Turkey. This paper presents the outburst data of coal mines in Turkey since 1969. Based on the observation of outburst occurrence in Turkey in the period from 1969 to 2012 as well as mining and geological conditions, detailed analysis of the possible causes of outburst accidents is conducted. The influences of some geological parameters such as the depth of occurrence, thickness and inclination of coal seams, the amount of ejected material (coal and gas), and tectonic disturbances on coal and gas outburst occurrences have been statistically investigated. The outburst occurrences throughout the world were reviewed and compared with the Turkish outburst experiences. Suggestions are put forward on future studies that could be of interest to government agencies regarding strategic policies, proper technical management practice, identification of outburst-prone coal seams, as well as prevention and control measures. 相似文献
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Marion Sautier Roger Martin-Clouaire Robert Faivre Michel Duru 《Climatic change》2013,120(1-2):341-355
Research aiming to reduce the vulnerability of agricultural systems to climate variability and change requires practical appraisal of their climatic exposure. We propose a method to map local climatic conditions over a given period to a set of productivity and management-related indicators that are specific to grassland-based livestock systems. Our method based on a reference system balances herbage production and feed requirements over a long period (≥ 30 years) and provides boundaries for productivity-defined seasons and indicators for surplus or shortage of herbage at seasonal and annual scales. This exposure-assessment method was applied to five climatically contrasting locations in south-western France. The trends and variability of the exposure indicators were analysed for past (1980–2010) and future (2035–2065) periods, considering the A1B scenario of the IPCC. Despite high year-to-year variability and the heterogeneity of the climatic situations studied, we show that climate change can modify the boundaries of productivity-defined seasons and seasonal herbage surplus or shortage. Moreover, the exposure indicators succeed in detecting climate-induced changes and distinguishing situations where a classical exposure indicator, such as annual forage production, could not. The exposure indicators highlight the forage productivity and the timing of production associated with local climatic conditions. These features fit the temporal scale at which farmers consider farm management and are highly suitable for identifying adaptation strategies that reduce the vulnerability of grassland-based livestock systems. 相似文献
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Ali Elmas Ersin Koralay Olgun Duru Alexander Schmidt 《International Geology Review》2017,59(4):420-447
Through the ?zmir–Ankara–Erzincan and the Vardar oceans suture zones, convergence between the Eurasian and African plates played a key role in controlling Palaeogene magmatism in northwestern Anatolia, northern Aegean, and eastern Balkans. LA-ICP-MS dating of U and Pb isotopes on zircon separates from the tuffs of the Harmankaya Volcanic Rocks, which are inter-fingered with the lower-middle Eocene deposits of the Gaziköy Formation to the north of the Ganos Fault and the Karaa?aç Formation in the Gelibolu Peninsula, yielded a late Ypresian (51 Ma) age. The chemical characteristics suggest that the lavas and tuffs of the Harmankaya Volcanic Rocks are products of syn- or post-collision magmas. These volcanic rocks show also close affinities to the subduction-related magmas. In addition to the already known andesitic volcanic rocks, our field observations in Gökçeada Island indicate also the existence of granitic and rhyolitic rocks (Marmaros Magmatic Assemblage). Our U–Pb zircon age data has shown that the newly discovered Marmaros granitic plutons intruded during late Oligocene (26 Ma) into the deposits of the Karaa?aç Formation in Gökçeada Island. LA-ICP-MS dating of U and Pb isotopes on zircon separates from the Marmaros rhyolitic rocks yielded a late Oligocene (26 Ma) crystallization age. Geochemical characteristics indicate that the more-evolved Oligocene granitic and rhyolitic rock of the Marmaros Magmatic Assemblage possibly assimilated a greater amount of crustal material than the lower Eocene Harmankaya Volcanic Rocks. Geochemical features and age relationships suggest increasing amounts of crustal contamination and a decreasing subduction signature during the evolution of magmas in NW Turkey from the early Eocene to the Oligocene. The magmatic activity developed following the northward subduction of the ?zmir–Ankara–Erzincan oceanic lithosphere and the earliest Palaeocene final continental collision between the Sakarya and Anatolide–Tauride zones. 相似文献
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Modeling stream flow and sediment yield using the SWAT model: a case study of Ankara River basin,Turkey 总被引：1，自引：0，他引：1
The Soil and Water Assessment Tool (SWAT) was tested for prediction of stream flow and sediment yield in the Ankara basin, Turkey. The overall objective of this study was to evaluate the performance and applicability of the SWAT and generate a soil erosion map. Thirteen years of daily/monthly flow and monthly sediment data were used for calibration and validation. Model performance was evaluated using statistical measures to assess the applicability of the model in simulating stream flow and sediment yield during calibration (1989–1996) and validation (1982–1984) periods. Nash Sutcliffe efficiency (NSE), relative error (RE), and R² (coefficient of determination) for daily flow were computed as 0.61, ?0.55, and 0.78, respectively; and as 0.79, ?0.58, and 0.89 for monthly flow during the calibration. Statistical comparisons of sediment yield produced values for NSE, RE, and R² of 0.81, ?1.55, and 0.93, respectively, during the calibration. The resulting map suggests that significant portions of urbanized and highly cultivated areas in the vicinity of stream channels are particularly vulnerable to soil erosion. SWAT satisfactorily simulated hydrology and sediment yield and can be used as a tool in decision-making for water resources planning in a basin with similar characteristics. 相似文献
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The effect of clay mineral content on the dynamic response of reconstituted fine grained soil 总被引：1，自引：0，他引：1
Fine grained soils with considerable amount of silt may exhibit sand-like or clay-like behavior depending on several factors such as the amount of fines and clay content, as well as the consistency limits, other variables being kept unchanged. This unpredictable behavior makes silts highly problematic, especially under seismic conditions. This paper describes the laboratory behavior of low plasticity Adapazari silt, known to be highly sensitive to cyclic loading. In the first phase of the basic study reported herein, Adapazari silt was mixed with different percentages of bentonite and kaolin and the behavior of these reconstituted mixtures was investigated in cyclic triaxial and dynamic simple shear tests. The purpose was to identify basic index properties and their threshold values to delineate sand- and clay-like behavior. Such a distinction may make it possible to complement field penetration resistance with appropriate adjustment factors to evaluate the pore pressure development potential, thus the risk of ground failure during an earthquake. The results show that there is a range of liquid limit and plasticity index values above which cyclic failure is significantly mitigated. It can now be stated that silts of intermediate and high plasticity may be deemed of relatively low potential for ground failure during seismic loading. 相似文献
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The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on the Mars Express (MEX) spacecraft is capable of measuring ionospheric electron density by the use of two main methods: remote radar sounding and from the excitation of local plasma oscillations. The frequency of the locally excited electron plasma oscillations is used to measure the local electron density. However, plasma oscillations are not observed when the plasma flow velocity is higher than about 160 km/s, which occurs mainly in the solar wind and magnetosheath. As a consequence, in many passes, there is a sudden disappearance of the plasma oscillations as the spacecraft enters into the magnetosheath. This fact allows us to identify a flow velocity boundary on the dayside, between the ionosphere of Mars and the shocked solar wind. This paper summarizes the results of the measurement of 552 orbits mostly over a period from August 4, 2005 to August 17, 2007. The boundary points found using MARSIS have been verified by measurements from the Analyzer of Space Plasma and Energetic Atoms (ASPERA-3) Electron Spectrometer (ELS) instrument on Mars Express. The average position of the flow velocity boundary is compared to flow velocity simulations computed using hybrid model and other boundaries. The boundary altitude is slightly lower than the magnetic pile-up boundary determined using Phobos 2 and Mars Global Surveyor (MGS) crossings, but it is in good agreement with the induced magnetospheric boundary determined by ASPERA-3. Investigation of the effect of the crustal magnetic field revealed that the flow velocity boundary is raised at the locations with strong crustal magnetic fields. 相似文献