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91.
Turkey confronts loss of life and large economic losses due to natural disasters caused by its morphologic structure, geographical placement, and climate characteristics. The Kuzulu (Koyulhisar) landslide, which caused loss of life and property on 17th March 2005, occurred in an area near the country’s most important active fault, the North Anatolian Fault Zone. To mitigate and prevent landslide damages, prediction of landslide susceptibility areas based on probabilistic methods has a great importance. The purpose of this study was to produce a landslide susceptibility map by the logistic regression and frequency ratio methodologies for a 733-km2 area near the North Anatolian Fault Zone from the southeast of Niksar to Resadiye in Tokat province. Conditioning parameters, such as elevation, slope gradient, slope aspect, distance to streams, roads, and faults, drainage density, and fault density, were used in the analysis. Before susceptibility analysis, the landslides observed in the area were separated into two groups for use in analysis and verification, respectively. The susceptibility maps produced had five different susceptibility classes such as very low, low, moderate, high, and very high. To test the performance of the susceptibility maps, area under curve (AUC) approach was used. For the logistic regression method, the AUC value was 0.708; while for the frequency rate method, this value was 0.744. According to these AUC values, it could be concluded that the two landslide susceptibility maps obtained were successful. 相似文献
92.
Lin Li Yani Najman Guillaume Dupont-Nivet Mauricio Parra Pierrick Roperch Mustafa Kaya Niels Meijer Paul O'Sullivan Gilby Jepson Jovid Aminov 《Basin Research》2023,35(2):530-550
Knowledge of the tectonic history of the Pamir contributes to our understanding of both the evolution of collisional orogenic belts as well as factors controlling Central Asian aridification. It is, however, not easy to decipher the Mesozoic–Cenozoic tectonics of the Pamir due to extensive Neogene deformation in an orogen that remains largely understudied. This study reports detrital apatite and zircon fission-track (FT) ages from both the eastern Tajik Basin sedimentary rocks and Pamir modern river sands. These FT data, supported by vitrinite reflectance and zircon and apatite U–Pb double dating, suggest that the majority of the FT ages are unreset and record exhumation stages of the Pamir, which has served as the source terrane of the Tajik Basin since the Cretaceous. Furthermore, we combine the new data with a compilation of published detrital apatite and zircon FT data from both the Tajik Basin sedimentary rocks and Pamir modern river sands, to explore the Mesozoic–Cenozoic tectonic history of Pamir. Deconvolved FT Peak Ages document two major Mesozoic exhumation events associated with the Late Triassic–Early Jurassic Cimmerian orogeny that reflects accretion of the Pamir terranes, as well as the Early–early Late Cretaceous deformation associated with the northward subduction of the Neo-Tethys Ocean beneath Pamir. The compiled data also show significant Late Eocene–Neogene exhumation associated with the ongoing formation of the Pamir, which peaks at ca. 36, 25, 14 and 7 Ma. 相似文献
93.
Karin Sesetyan Can ZulfikarMine Demircioglu Ufuk HancilarYaver Kamer Mustafa Erdik 《Soil Dynamics and Earthquake Engineering》2011
Potential impact of large earthquakes on urban societies can be reduced by timely and correct action after a disastrous earthquake. Modern technology permits measurements of strong ground shaking in near real-time for urban areas exposed to earthquake risk. The Istanbul Earthquake Rapid Response System equipped with 100 instruments and two data processing centers aims at the near real time estimation of earthquake damages using most recently developed methodologies and up-to-date structural and demographic inventories of Istanbul city. The methodology developed for near real time estimation of losses after a major earthquake consists of the following general steps: (1) rapid estimation of the ground motion distribution using the strong ground motion data gathered from the instruments; (2) improvement of the ground motion estimations as earthquake parameters become available and (3) estimation of building damage and casualties based on estimated ground motions and intensities. The present paper elaborates on the ground motion and damage estimation methodologies used by the Istanbul Earthquake Rapid Response System with a special emphasis on validation and verification of the different methods. 相似文献
94.
Nurcan Meral Ozel Necmioglu Ocal Yalciner Ahmet Cevdet Dogan Kalafat Mustafa Erdik 《Soil Dynamics and Earthquake Engineering》2011
Tsunami mitigation, preparedness and early warning initiatives have begun at the global scale only after the tragic event of Sumatra in 2004. Turkey, as a country with a history of devastating earthquakes, has been also affected by tsunamis in its past. In this paper we present the Tsunami Hazard in the Eastern Mediterranean and its connected seas (Aegean, Marmara and Black Sea) by providing detailed information on historically and instrumentally recorded significant tsunamigenic events surrounding Turkey, aiming to a better understanding of the Tsunami threat to the Turkish coasts. In addition to the review of the Tsunami hazard, we have studied a possible Tsunami source area between Rhodes and SW of Turkey using Tsunami numerical model NAMI DANCE-two nested domains. We have computed a maximum positive amplitude of 1.13 m and maximum negative amplitude of −0.5 m at the Tsunami source by this study. The distribution of maximum positive amplitudes of the water surface elevations in the selected Tsunami forecast area and time histories of water level fluctuations near selected locations (Marmaris, Dalaman, Fethiye and Kas towns) indicate that the maximum positive amplitude near the coast in the selected forecast area exceeds 3.5 m. The arrival time of maximum wave to Marmaris, Dalaman, is 10 min, while that of Fethiye and Kas towns is 15–20 min. The maximum positive amplitudes near the shallow region of around 10 m depth are 3 m (Marmaris), 1 m (Dalaman), 2 m (Fethiye) and 1 m (Kas). Maximum positive amplitudes of water elevations in the duration of 4 h simulation of the Santorini-Minoan Tsunami in around 1600 BC in the Aegean Sea are also calculated based on a simulation performed using 900 m grid resolution of Aegean sea bathymetry with a 300 m collapse of 10 km diameter of Thera (Santorini) caldera. We have also presented the results of the Tsunami modeling and simulation for Marmara Sea obtained from a previous study. Last part of this paper provides information on the establishment of a Tsunami Warning Center by KOERI, which is expected to act also as a regional center under the UNESCO Intergovernmental Oceanographic Commission – Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North-Eastern Atlantic, the Mediterranean and Connected Seas (ICG/NEAMTWS) initiative, emphasizing on the challenges together with the future work needed to be accomplished. 相似文献
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Ganju Eshan Kılıç Mustafa Prezzi Monica Salgado Rodrigo Parab Niranjan Chen Wayne 《Acta Geotechnica》2021,16(11):3489-3516
Acta Geotechnica - This paper presents the results and analyses of uniaxial compression experiments performed on three silica sands. The sands have comparable particle-size distributions, but their... 相似文献
100.
Ibrahim M. J. Mohialdeen Karwan A. Mustafa Danyar A. Salih Mark A. Sephton Diyar A. Saeed 《Arabian Journal of Geosciences》2018,11(3):51
The Miran oilfield is one of the new oil fields in Kurdistan region, northern Iraq, located in the Sulaimani Governorate. Twelve Cuttings samples from the Upper Jurassic Naokelekan and Barsarin formations in well Miran-2 were selected for detailed organic geochemical investigations. All the samples were subjected to bitumen extraction in order to study any biomarkers present using gas chromatography-mass spectrometry. The dominance of low-molecular-weight n-alkanes and other calculated parameters indicate a marine source for the organic matter derived from planktonic algal and bacterial precursors deposited under anoxic conditions. The isoprenoids/n-alkanes ratios indicate type II and mixed II/III kerogen for both formations. The type II/III kerogen is characteristic of transitional environment under anoxic to dysoxic conditions as also indicated by the homohopane index for studied samples. More argillaceous carbonate rocks were deposited when reducing conditions were prevalent. Medium to high gammacerane index values in the rock extracts probably indicate a stratified water column during deposition of both formations. The studied samples from both formations have entered peak oil window maturity as reflected from the biomarker ratios from both aliphatic and aromatic fractions of the extracts. 相似文献