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The aim of this study was to conduct flood analysis with digital modeling systems and estimate the total flood damage in a built-up area. The Ceviz Stream basin, which is located in Unye (Ordu) district in the Eastern Black Sea region of Turkey, was selected as the study area. A 1D/2D coupled flood modeling software MIKE FLOOD was used in flood analysis. According to the modeling results, water depth and velocity maps are produced for maximum Q50, Q100, Q500 and Q1000 discharge scenarios in the most downstream section of the Ceviz Stream. At the projected Q50, Q100, Q500 and Q1000 maximum flow rates, approximately 9.75%, 23.0%, 30.0% and 32.25% of that section of the study area were estimated to be negatively affected by floodwaters. In order to examine the financial magnitude of the effects of flooding, the Huizinga, van Eck and Kok, ICBR and Pistrika and Jonkman damage estimation methodologies were applied, with the highest financial costs estimated with the Pistrika and Jonkman method.
相似文献3.
An isotope-geochronological study has been performed to examine the products of Late Cenozoic collision volcanism on the northern
coast of Lake Van, Turkey. We obtained 45 new K—Ar dates, based on which the principal time characteristics of volcanic activity
in the region have been determined. Volcanic activity in the northern coast of Lake Van has lasted ∼15 myr; it has had an
expressed discrete nature, when periods of intense volcanic activity alternated with long-lasting pose periods. Four stages
of Neogene—Quaternary volcanism have been identified: Middle Miocene (15.0—13.5 Ma), Late Miocene (10—9 Ma), Pliocene (5.8—3.7
Ma), and Quaternary (1.0—0.4 Ma). The average duration of the stages was 1—2 myr; the stages were separated from each other
with periods of inactivity of approximately equal lengths (∼3 myr). For each of the Pliocene and Quaternary stages, three
additional phases of volcanism have been identified, which were separated from each other with short time intervals (a few
hundred thousand years). The last burst of volcanic activity in the study area occurred ∼400 ka; similar to Quaternary volcanism
in general, it was not characterized by a high intensity. An important result of the studies performed was to confirm the
existence of a separate Middle Miocene stage of collision volcanism for the Caucasian—Anatolian Segment of the Alpine Fold
Belt. New geochronological data generated presented in this paper indicate that Neogene—Quaternary volcanism in this portion
of the belt started much earlier (∼15 Ma) than assumed by the majority of the previous researchers. 相似文献
4.
Z. Tunca V. Keskin S. Evren C. Ibanoglu M. C. Akan 《Astrophysics and Space Science》1993,204(2):297-304
Two-colour photometric observations of the white-dwarf and K-dwarf eclipsing binary V471 Tau were made during the last four years. The resulting light curves and thirteen timings of mid-eclipse are presented. During the observations two flares were obtained on September 23 and December23, 1992. Both events occurred just after the fourth contact. The increment in the brightness was measured as 0
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m
067. The energy liberated by the flare was computed to be 5.43 × 1032 erg s–1 in the JohnsonB band, which amounts 1.13 times that of the total radiation of the K-dwarf. 相似文献
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Two-colour photoelectric photometry of the eclipsing binary BD + 13o4708 was carried out. Several features such as asymmetry in the branches, light difference between the maxima, an eccentric orbit, a dip around phase 0.2 are distinctive. The new light elements of the system were computed using also the previous times of primary minima given by Walker (1988). 相似文献
6.
M. Keskin A. V. Chugaev V. A. Lebedev E. V. Sharkov V. Oyan O. Kavak 《Journal of Volcanology and Seismology》2012,6(6):352-360
This paper considers results from isotope-geochronological (K-Ar) studies of the products of Neogene-Quaternary volcanism in the Karacada? area, which is situated within the northern frontal part of the Arabian plate. It was found that magmatic activity has been evolving at this location for at least the last 11–10 Myr and was distinctly discrete in character. Three stages of volcanism have been identified: (I) Early or Miocene, ～11–6.7 Ma; (II) Middle or Pliocene-Early Quaternary, 4–1 Ma; and (III) Late or Late Quaternary, 0.4–0.1 Ma. The most recent manifestations of magmatic activity in the region date back to about 100000 years ago. An analysis of the spatial distribution of volcanic centers of different ages in the Karacada? neovolcanic area shows that the magmatism of that region involved a lateral migration of activity from northwest to southeast along a major regional tectonic fault. The migration was caused by the movement of local tension zones where the lithosphere was thinner and deep-seated mantle magmas were ascending. 相似文献
7.
Heavy metal pollution in the surrounding ore deposits and mining activity: a case study from Koyulhisar (Sivas-Turkey) 总被引：1，自引：1，他引：0
The oxidation of sulfide minerals generates acidic waters containing high levels of SO4 and Fe. The study area has active Pb?CZn?CCu mining. It is thought that the surface/subsurface/underground sulfide minerals in the region generally contribute to the acidification of groundwater. Low pH values are also responsible for dissolved metals (Al, Fe, Mn, SO4, Pb, Zn) in the groundwater and river. Furthermore, current mining wastes have affected concentrations of trace elements in the water. High Fe and Mn concentrations are generally found in the spring which has acidic and low Eh values, while Al, Fe and Mn concentrations in the acidic waters show notable increases with the maximum values reaching 8,829, 19,084 and 1,708?ppb, respectively. These values exceed the Turkish drinking water standard of 200, 200 and 50?ppb, respectively. 相似文献
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Geochronology of Late Cenozoic volcanism in the area of Van Lake,Turkey: An example of development dynamics for magmatic processes 总被引：1，自引：0，他引：1
An isotope-geochronological study has been performed to examine the products of Late Cenozoic collision volcanism on the northern
coast of Van Lake, Turkey. We obtained 45 new K-Ar dates, based on which the principal time characteristics of volcanic activity
in the region have been determined. The total duration of magmatic activity in the area of the northern coast of Van Lake
has lasted ∼15 myr; it has had an expressed discrete nature, when periods of intense volcanic activity alternated with lasting
breaks in eruptions. Four stages of Neogene-Quaternary volcanism have been identified: Middle Miocene (15.0–13.5 myr), Late
Miocene (10–9 myr), Pliocene (5.8–3.7 myr), and Quaternary (1.0–0.4 Ma). The average duration of the stages has been 1–2 myr;
the stages were separated from each other with periods of inactivity of approximately equal lengths (∼3 myr). For each of
the Pliocene and Quaternary stages, three additional phases of volcanism have been identified, which were separated from each
other with short time intervals (a few hundred thousand years). The last burst of volcanic activity in the area in question
took place ∼400 ka; similar to Quaternary volcanism in general, it was not characterized by a high intensity. An important
result of the studies performed was to confirm the existence of a separate Middle Miocene stage of collision volcanism for
the Caucasian-Anatolian Segment of the Alpine Fold Belt. The data generated allow concluding that Neogene-Quaternary volcanism
in this portion of the belt started much earlier (∼15 Ma) than assumed by the majority of the previous researchers. 相似文献
10.
The Eastern Anatolia Region exhibits one of the world's best exposed and most complete transects across a volcanic province related to a continental collision zone. Within this region, the Erzurum–Kars Plateau is of special importance since it contains the full record of collision-related volcanism from Middle Miocene to Pliocene. This paper presents a detailed study of the volcanic stratigraphy of the plateau, together with new K–Ar ages and several hundred new major- and trace-element analyses in order to evaluate the magmatic evolution of the plateau and its links to collision-related tectonic processes. The data show that the volcanic units of the Erzurum–Kars Plateau cover a broad compositional range from basalts to rhyolites. Correlations between six logged, volcano-stratigraphic sections suggest that the volcanic activity may be divided into three consecutive Stages, and that activity begins slightly earlier in the west of the plateau than in the east. The Early Stage (mostly from 11 to 6 Ma) is characterised by bimodal volcanism, made up of mafic-intermediate lavas and acid pyroclastic rocks. Their petrography and high-Y fractionation trend suggest that they result from crystallization of anhydrous assemblages at relatively shallow crustal levels. Their stratigraphy and geochemistry suggest that the basic rocks erupted from small transient chambers while the acid rocks erupted from large, zoned magma chambers. The Middle Stage (mostly from 6–5 Ma) is characterised by unimodal volcanism made up predominantly of andesitic–dacitic lavas. Their petrography and low-Y fractionation trend indicate that they resulted from crystallization of hydrous (amphibole-bearing) assemblages in deeper magma chambers. The Late Stage (mostly 5–2.7 Ma) is again characterised by bimodal volcanism, made up mainly of plateau basalts and basaltic andesite lavas and felsic domes. Their petrography and high-Y fractionation trend indicate that they resulted from crystallization of anhydrous assemblages at relatively shallow crustal levels. AFC modelling shows that crustal assimilation was most important in the deeper magma chambers of the Middle Stage. The geochemical data indicate that the parental magma changed little throughout the evolution of the plateau. This parental magma exhibits a distinctive subduction signature represented by selective enrichment in LILE and LREE thought to have been inherited from a lithosphere modified by pre-collision subduction events. The relationships between magmatism and tectonics support models in which delamination of thickened subcontinental lithosphere cause uplift accompanied by melting of this enriched lithosphere. Magma ascent, and possibly magma generation, is then strongly controlled by strike-slip faulting and associated pull-apart extensional tectonics. 相似文献