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Landslide susceptibility mapping for a landslide-prone area (Findikli,NE of Turkey) by likelihood-frequency ratio and weighted linear combination models 总被引：17，自引：0，他引：17
Landslides are very common natural problems in the Black Sea Region of Turkey due to the steep topography, improper use of
land cover and adverse climatic conditions for landslides. In the western part of region, many studies have been carried out
especially in the last decade for landslide susceptibility mapping using different evaluation methods such as deterministic
approach, landslide distribution, qualitative, statistical and distribution-free analyses. The purpose of this study is to
produce landslide susceptibility maps of a landslide-prone area (Findikli district, Rize) located at the eastern part of the
Black Sea Region of Turkey by likelihood frequency ratio (LRM) model and weighted linear combination (WLC) model and to compare
the results obtained. For this purpose, landslide inventory map of the area were prepared for the years of 1983 and 1995 by
detailed field surveys and aerial-photography studies. Slope angle, slope aspect, lithology, distance from drainage lines,
distance from roads and the land-cover of the study area are considered as the landslide-conditioning parameters. The differences
between the susceptibility maps derived by the LRM and the WLC models are relatively minor when broad-based classifications
are taken into account. However, the WLC map showed more details but the other map produced by LRM model produced weak results.
The reason for this result is considered to be the fact that the majority of pixels in the LRM map have high values than the
WLC-derived susceptibility map. In order to validate the two susceptibility maps, both of them were compared with the landslide
inventory map. Although the landslides do not exist in the very high susceptibility class of the both maps, 79% of the landslides
fall into the high and very high susceptibility zones of the WLC map while this is 49% for the LRM map. This shows that the
WLC model exhibited higher performance than the LRM model. 相似文献
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Erdem Emin Maras Mustafa Caniberk Mehmet Serhat Odabas Burcu Degerli Süleyman Sirri Maras Hadi Hakan Maras 《Arabian Journal of Geosciences》2016,9(2):164
We investigated the relationships between mineral content and the physical and mechanical properties of landscape rock using a non-destructive remote sensing method applied in the laboratory. Using this technique, the spectral properties of the landscape rock could be collected at different wavelengths without harming the samples. Differences in spectral reflectance were compared with the physical and mechanical properties of the stone. Significant correlations were observed between reflectance values and the rocks’ mechanical and physical properties, with correlation coefficients of 95 to 99 %. However, establishing a correlation between two variables is not a sufficient condition to establish a causal relationship. Mineral densities and mineral content are characteristics used for the classification of landscape rock. We have concluded that although spectral signatures from landscape rock can be used for predicting which stones might have similar features when comparing two batches of stone, the high correlations we discovered cannot confirm a cause and effect relationship that would allow for the prediction of a rock’s physical and mechanical properties. Although this conclusion is disappointing, the mineral content and the significant correlations discovered by hyperspectral reflectance scanning can be used as supplementary information when comparing two samples of landscape rock. 相似文献
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Serhat?K?ksal Rolf?L.?Romer M.?Cemal?G?ncüoglu Fatma?Toksoy-K?ksalEmail author 《International Journal of Earth Sciences》2004,93(6):974-989
The last stages of the continental collision during the closure of the Neotethyan ocean in central Anatolia are characterized by post-collisional H- and A-type granitoids intruding both the metamorphic country rocks and allochthonous ophiolitic rocks of the central Anatolian crystalline complex. Available Rb–Sr and K–Ar whole-rock and mineral age data on the H- and A-type granitoids in central Anatolia are inconsistent. To better constrain the geological relevance and the timing of the change in the chemical character of magmatism in the wake of the Alpine orogeny in Anatolia, we re-evaluated the geochemical characteristics and dated titanite from representative H- (Baranadag quartz-monzonite: BR) and A-type (Çamsari quartz-syenite: CS) granitoids by the U–Pb method. BR is a high-K calc-alkaline intrusion with mafic microgranular enclaves and shows enrichment of LILE relative to HFSE. The alkaline CS displays higher SiO2, Na2O+K2O, Fe/Mg, Rb, Th and HFSE with corresponding depletion in CaO, MgO, Fe2O3tot, P2O5, Ba, Sr, and Ti. Chondrite-normalized REE patterns of the BR and CS samples have LREE-enriched and flat HREE patterns, whereas CS differs from BR by higher LREE enrichment and lower MREE and HREE contents. Mineralogical and geochemical characteristics suggest that BR and CS were not products of the same magma source. BR was derived from a subduction-modified depleted hybrid-source and CS had an enriched mantle source with significant crustal contribution. The U–Pb titanite ages of the H-type central Anatolian granitoids (BR) and the A-type granitoids (CS) are 74.0±2.8 and 74.1±0.7 Ma, respectively. The coeval evolution of post-collisional/calc-alkaline H- to A-type magmatism was possibly associated with source heterogeneity and variable involvement of continental materials during the evolution of these granitoids. These new age data constrain the timing of the onset of a post-collision extensional period following the Alpine thickening within the passive margin of the Tauride–Anatolide platform, which occurred before the opening of the latest Cretaceous central Anatolian basins.An erratum to this article can be found at 相似文献
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Sermin Tagil Sevgi Gormus Serhat Cengiz 《Journal of the Indian Society of Remote Sensing》2018,46(8):1285-1296
Perforation, dissection, fragmentation, shrinkage and attrition in ecosystems take place due to urbanization. In this study, where and when temporal and spatial heterogeneity occurs is tried to be explained by taking human intervention in landscape pattern and processes in and around the city of Denizli into account and how this heterogeneity affects habitat conditions within the scope of landscape ecology. Landscape pattern metrics were estimated in order to reveal the change in habitats and present the properties of the landscape. 30 pattern indicators on class and pattern levels, which are important to show human–environment interaction, were analyzed in order to indicate the features of the landscape such as area, side, shape and dispersion. To this end, LANDSAT TM/7–ETM/8-OLI satellite images of 1987 and 2013 were classified for laying the foundations of the analysis. Analyses showed that between 1987 and 2013, complicated shape features, increase in edge habitats, de-growth in core areas and eventually fragmentation in landscape have been dominant. Heterogenic structure in landscape has increased. This points not to the self-functioning of the landscape, but to the domination of human intervention over the landscape. Particularly, due to urban growth and sprawl, fragmentation, isolation and habitat loss in croplands have increased. This study sets forth the usefulness of remote sensing, GIS and landscape metrics in understanding how urban dynamics and ecosystems change in developing urban politics. 相似文献
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Analysis of ambient noise in Yalova, Turkey: discrimination between artificial and natural excitations 总被引：2，自引：2，他引：0
Ambient noise measurements acquired in Yalova, which was highly damaged during the 1999 Izmit earthquake, are analyzed to explore the site characteristics. The region of Yalova is governed by complex geological and geomorphological structures consisting of river beds extending from the mountains to the sea, ridges between them, plains in front of them with different size, and the sea coast. As a result of these shallow geological features, the H/V curves exhibit complex patterns. Clear peaks in the H/V curves, which can be interpreted as reliable site resonance frequency, are observed only at about half of the measurement sites. At the remaining sites industrial peaks, broad peaks, or flat responses dominate the spectral ratio graphs. We observed that man-made noises generated by marble cutting machines in Hersek delta mask the site resonance frequencies or can be misinterpreted as a resonance frequency. In total, we identified three anthropogenic noise sources at fundamental frequencies of 1.3, 1.5, and 1.7 Hz along with their two- and threefold harmonics. The parts of H/V curves showing unusual low scattering can be a clue to identify anthropogenic effects. In the assessment of H/V curves, the site location and the similarity of the near surface geology were taken into account. The Laledere plain with thick and soft sediment sequence surprisingly displays flat responses due to a possible low impedance contrast. The Ciftlikkoy and Hacimehmet plains exhibit clear resonance peaks at nearly 1 Hz possessing the largest amplitudes. These sites experienced the highest damage in Yalova during the Izmit earthquake. In contrast, the Cinarcik region which was also exposed to high damage, do not show any obvious amplifications on the H/V curves. Generally, the H/V curves for valley and ridge sites in Yalova reveals a resonance peak at approximately 1 Hz and almost flat curves, respectively. However, several sites on the ridges and valleys portray different patterns. 相似文献
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In the present study, Oreganum onites L. stalks in natural and chemically modified with HNO3 and H3PO4 used as adsorbent for removal of both acidic and basic dyes from waters. The adsorption was studied as a function of pH and contact time by batch method. All tested biosorbents were characterized by FT‐IR, scanning electron microscopy, and measuring the pH dependence of the zeta potential. The adsorption isotherms were fitted to Langmuir isotherm. The maximum adsorption capacity of dyes was 280.73 mg g?1 for Basic Red 18, 147.06 mg g?1 for methylene blue and 112.36 for Acid Red 111, which is comparable to that of other lignocellulosic materials. The modification process was considerably increased the biosorption capacity of lignocellulosic material, resulting in a 56–63% increase in the biosorption capacity of basic dyes and a 125% increase in the biosorption capacity of acidic dye. The present study illustrated that the most effective factors in the adsorption of basic dye were surface charge and acidic groups on lignocellulosic biosorbents, while non‐electrostatic forces as well as electrostatic forces were also effective in the adsorption of acidic dye. In conclusion, Oreganum stalks can be considered as a very prospective adsorbent for the removal of tested basic and acidic dyes. 相似文献
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Serhat Dağ 《山地科学学报》2018,15(10):2307-2319
The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) standard in rocks is sufficient or not, and to examine how the degree of saturation of rocks may be determined as a function of time. For this purpose, samples from five different rock groups including igneous(andesite, granite, andesitic tuff) and sedimentary(limestone, sandstone) exposed in Gümü?hane city which is from mountainous area of north-eastern Turkey, have been compiled. Measurements were taken on the samples left for saturation under laboratory conditions as a result of which the degree of saturation values at the end of these time periods were determined. Similarly, at the end of 48 hours, the samples were left to dry under atmospheric conditions in the laboratory environment and their time dependent degree of saturation were also calculated at different times. The changes as a function of time in the degree of saturation were then examined mathematically using non-linear, exponential and logarithmic functions. Graphs and equations related with the acquired time-degree of saturation values and the correlation coefficient(r) values for these equalities have indicated a high accordance between time and degree of saturation for the studied rock groups. The applied methodology will be beneficial for determining the degree of saturation based on time for engineering studies that will be carried out in similar lithologies. 相似文献