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Ground motion intensity parameters of past and potential earthquakes are required for a range of purposes including earthquake insurance practice. In regions with no or sparse earthquake recordings, most of the available methods generate only peak ground motion parameters. For cases where full ground motion time histories are required, simulations that consider fault rupture processes become necessary. In this study, a major novel use of simulated ground motions is presented in insurance premium calculations which also require ground motion intensity measures that are not always available through observations. For this purpose, potential earthquakes in Bursa are simulated using stochastic finite-fault simulation method with dynamic corner frequency model. To ensure simulations with reliable synthetic ground motions, input parameters are derived from regional data. Regional model parameters are verified by comparisons against the observations as well as ground motion prediction equations. Next, a potential large magnitude event in Bursa is simulated. Distribution of peak ground motion parameters and time histories at selected locations are obtained. From these parameters, the corresponding Modified Mercalli Intensities (MMI) are estimated. Later, these MMIs are used as the main ground motion parameter in damage probability matrices (DPM). Return period of the scenario earthquake is obtained from the previous regional seismic hazard studies. Finally, insurance rates for Bursa region are determined with implementation of two new approaches in the literature. The probability of the scenario event and the expected mean damage ratios (MDR) from the corresponding DPMs are used, and the results are compared to Turkish Catastrophe Insurance Pool (TCIP) rates. Results show that insurance premiums can be effectively computed using simulated ground motions in the absence of real data. 相似文献
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Ofer Marder Reuven Yeshurun Ronit Lupu Guy Bar‐Oz Miriam Belmaker Naomi Porat Hagai RON Amos Frumkin 《第四纪科学杂志》2011,26(8):769-780
Rantis Cave is a recently discovered filled cave in central Israel, displaying a rich faunal accumulation of micromammals, ungulates and carnivores. U–Th dating assigns the beginning of accumulation to ca. 140 ka. The accumulation is culturally assigned to the late half of the Middle Paleolithic (MP) period. Single‐grain optically stimulated luminescence measurements attest to a complex sedimentological history. We present the cross‐disciplinary results of taphonomic and geomorphological analyses, which point to the cave serving as a natural pitfall trap for the large fauna, with little human or carnivore activity. The fauna is dominated by Dama among the ungulates and by Microtus among the micromammals. These data in conjunction with ungulate tooth mesowear analysis suggest a xeric Mediterranean environment on the eastern margin of the southern Levantine foothills. The relative taxonomic abundance of ungulate taxa shows some differences from anthropogenic MP sites, possibly reflecting the prey choice patterns of MP hunters. Overall, the natural accumulation scenario for Rantis Cave provides a rare paleoenvironmental and paleoeconomic reference to the rich anthropogenic MP faunas of the Southern Levant, enabling the reconstruction of a rich and diverse environmental setting for this important human dispersal route. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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In order to study the impact of produced water (PW) from a North Sea oil field on blue mussels (Mytilus edulis), chemical and biological markers were selected. A laboratory exposure (0.125%, 0.25% and 0.5% of PW) and a field study (6 stations 0.2-2 km from a PW discharge point) were conducted. In the laboratory study, PAH bioaccumulation increased in mussel soft tissue even at the lowest exposure dose. Micronuclei frequency demonstrated a dose-response pattern, whereas lysosomal membrane stability showed tendency towards a dose-response pattern. The same markers were assessed in the field study, biomarker analyses were consistent with the contamination level, as evaluated by mussel polycyclic aromatic hydrocarbons body burden. Overall, obtained results confirmed the value of an ecotoxicological approach for a scientifically sound characterisation of biological effects induced by offshore oilfield operational discharges. 相似文献
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Temporal soil erosion risk evaluation: a CORINE methodology application at Elmalı dam watershed,Istanbul 总被引：1，自引：0，他引：1
Geographical information systems (GIS)-based soil erosion risk assessment models continue to play an important role in soil
conservation planning. In the present study, soil erosion risk of Istanbul–Elmalı dam watershed was determined within GIS-based
COoRdination of INformation on the Environment (CORINE) soil erosion risk assessment method. Initially soil texture, soil
depth, and surface stoniness maps were created and were intersected in GIS environment in order to generating erodibility
map. Then, Fournier precipitation and Bagnouls–Gaussen drought indices determined based on meteorological data and erosivity
were calculated. The composed erodibility map was co-evaluated within erosivity value and slope map of the site for composing
potential erosion risk map. At the final step, the previous yearly land use maps which belong to years 1984, 1992, and 2003
intersected with potential erosion risk maps and temporal actual erosion risk alteration were assessed. In conclusion, according
to our results in Elmalı watershed dam in 1984 there have been low, medium, and high erosion risks at rates 29.67, 52.49,
and 17.84%, respectively, whereas in 2003 the erosion risk values have changed from low to high as 26.43, 46.57, and 27.00%,
respectively. Inter-year comparison alteration to the advantage of the high erosion risk could have resulted from over degradation
and high exposure to anthropogenic activities. 相似文献
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Modeling of a Multiply Jointed Voussoir Beam in the Centrifuge 总被引：3，自引：1，他引：3
Summary The mechanics and kinematics of a multiply jointed Voussoir beam have been studied based on the response of small scale beams
tested in the centrifuge. The model beams were made up of six blocks, confined between fixed abutments. The tests included
monitoring of beam deflection, development of axial thrust and distribution of strain within the beam. The models were subjected
to accelerations of up to 90 g, depending upon the beam geometry. Two different beam geometries were considered.
The test data were analysed in the light of pseudo analytical algorithms accepted in the analysis of singly jointed Voussoir
beams. The data show that small translations and rotations of the block at the beam-abutment interface are required for a
stable compression arch to set up in the beam. The computations and physical models indicate that the development of thrust
is in linear proportion with the applied acceleration and is independent of beam thickness. The distribution of strains along
the beam leads to the conclusion that the depth of the compression arch varies from the total beam thickness, to approximately
one half of the beam thickness, under stable conditions. The data should be of considerable use to researchers looking to
calibrate/validate numerical techniques used in describing the response of discontinuous rock masses. 相似文献
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Helena Mouriño Maria Isabel Barão 《Stochastic Environmental Research and Risk Assessment (SERRA)》2010,24(4):499-511
In this paper we consider a Linear Regression Model with a design matrix that fits the periodic structure of a time series.
As a consequence, the residuals are very often autocorrelated. The main problem is that residual autocorrelation does not
necessarily entail error autocorrelation. To analyse the effects of selecting different formulations to accommodate the autocorrelation
in the residuals, we consider two seemingly different ways to deal with this problem: the Linear Regression Model with the
error terms following an Autoregressive Stationary Process and the Partial Adjustment Model. We study the equivalence between
the two formulations. We go over the problem of estimating the parameters and, especially, of making inferences in this framework.
After parameter estimation, we analyse the adequacy of the models. We demonstrate that the issue of selecting the most appropriate
model to capture the autocorrelation in the residuals is, in this context, a kind of an artefact since the main results concerning
the fitted values and forecasting features are the same. These modelling procedures are applied to the Portuguese coastal
upwelling data and we compare the estimated models. 相似文献
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This study reported the mass mortality events (MMEs) of Pinna nobilis based on diving surveys in Turkey. Data were collected across 12 sites in the Aegean Sea, and one site in the Sea of Marmara, within the period of June-September 2019. The results showed that a low mortality rate of 10% was found in the Sea of Marmara, and a MME was not detected for this area. In contrast, 97% mortality was recorded for the P. nobilis population distributed in the Turkish Aegean Sea. This discrepancy might be related to the seawater temperature and salinity values of these two seas. The waters of the Sea of Marmara were colder and less salty than the Aegean Sea. The findings highlighted the importance of protecting the healthy population of critically endangered fan mussels in the Sea of Marmara. It was recommended that sound management plans comprising of monitoring, enforcement and public awareness activities could be implemented in order to achieve this. 相似文献
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Levent Şaylan Barış Çaldağ Fatih Bakanoğulları Hüseyin Toros Mustafa Yazgan Orhan Şen Yunus Özkoca 《洁净——土壤、空气、水》2011,39(5):491-501
Pollutants affect not only the environment in which they originate since they are also transported by air currents to other locations. For this reason, air pollution is a global problem for all countries and the air and water quality need to be monitored carefully. More information on precipitation chemistry is required to determine the source of pollution as well as its effects on the ecosystems. In this study, precipitation chemistry has been analyzed for the first time by using simple bulk collectors located at four different sites in Northwest Turkey for a period of two years. About 650 sequential rainwater samples were collected and analyzed for pH, electrical conductivity, anions such as , , Cl?, and cations such as Na+, K+, Mg2+, Ca2+, and . The selected sites were under the effect of different environmental factors. Our results showed that the highest and concentrations were measured in the Northwest of the research area. Additionally, it has been found that Ca2+ ions are abundant within all rainwater samples. 相似文献