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A review on the historical evolution of seismic hazard maps in Turkey is followed by summarizing the important aspects of the updated national probabilistic seismic hazard maps. Comparisons with the predecessor probabilistic seismic hazard maps as well as the implications on the national design codes conclude the paper.  相似文献   
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This work presents new 87Sr/86Sr and δ88/86SrSRM987 isotopic values of thirteen mineral, vegetal and animal reference materials. Except for UB‐N, all our results are consistent with previously published data. Our results highlight intermediate precisions among the best presently published and a non‐significant systematic shift with the calculated δ88/86SrSRM987 mean values for the three most analysed reference materials in the literature (i.e., IAPSO, BCR‐2 and JCp‐1). By comparison with the literature and between two distinct digestions, a significant bias of δ88/86SrSRM987 values was highlighted for two reference materials (UB‐N and GS‐N). It has also been shown that digestion protocols (nitric and multi‐acid) have a moderate impact on the δ88/86SrSRM987 isotopic values for the Jls‐1 reference materials suggesting that a nitric acid digestion of carbonate can be used without significant bias from partial digestion of non‐carbonate impurities. Different δ88/86SrSRM987 values were measured after two independent Sr/matrix separations, according to the same protocol, for a fat‐rich organic reference material (BCR‐380R) and have been related to a potential post‐digestion heterogeneity. Finally, the δ88/86SrSRM987 value differences measured between animal‐vegetal and between coral‐seawater reference materials agree with the previously published results, highlighting an Sr isotopic fractionation along the trophic chain and during carbonate precipitation.  相似文献   
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Geotechnical and Geological Engineering - The aggregates consist approximately 85% of the total volume in asphalts pavements, and their properties influence directly their behavior. Therefore, it...  相似文献   
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The priority of flood management planning is physical victimization and focuses on taking structural measures. Although this approach is an accurate approach, more information is needed in implementing efficient precautionary and planning decisions. It is an indisputable fact that the existence of nothing that is not sustainable in nature cannot continue. Hence, it is necessary to implement a planning decision suitable for the structure of the population living in the region so that the continuity of the policies to be carried out against natural hazards of hydrometeorological origin such as a flood is ensured. How the socio-demographic structures affect the flood risk perception of 245 people living in the city center of Bayburt is examined in this study. It is the first research conducted for the province of Bayburt for this perspective. The participants were asked to fill a questionnaire containing 24 items and consisting of 2 sections. T test and one-way ANOVA (one-way analysis of variance) statistical methods were used to ascertain the difference between the responses of the participants to the questionnaire, based on their demographic structure. As the result of the study, significant differences were observed between the expressions depicting flood risk perception and the participant's age, income levels and educational background. In addition, it has been noted that there is a positive relationship between education and income levels and flood risk perception.

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In this study, we investigate the Lesser Antilles forearc basin, focusing on the late Pliocene to Pleistocene sedimentary archives in order to track the occurrence of extreme events triggered by enhanced subduction‐related tectono‐volcanic activity. We identify late Piacenzian deposits covering a major regional erosional surface, displaying sedimentary dykes and large marine boulders embedded in a mixed continental–marine matrix, characteristic of tsunamites. We interpret this episode of platform emersion and the successive cataclysmic deposits as resulting from enhanced tectonic activity at the interface of the subduction zone, synchronous with the initiation of the Lesser Antilles volcanic arc. We then discuss the implications in terms of the mechanical behaviour of the Lesser Antilles subduction zone.  相似文献   
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Post‐infrared (pIR) stimulated luminescence dating of sedimentary feldspar largely avoids the effects of anomalous fading that affect conventional infrared stimulated luminescence (IRSL) dating. However, optical resetting of pIR signals is more difficult than resetting the conventional IRSL signal, which may undermine the crucial assumption that pIR signals were effectively bleached upon deposition and burial of sediment grains. In this study, we quantify the bleaching properties of several pIR signals on various samples using laboratory‐simulated bleaching in full sunlight and water‐attenuated sunlight. Our data show that bleaching is most efficient under full spectrum conditions for all pIR signals and that pIR signals measured at elevated temperature are increasingly harder to bleach than IR and pIR signals measured at low temperature (e.g. IR at 50°C). All bleaching curves exhibit a very slow and steady decrease, indicating that a fixed un‐bleachable residual level cannot be reached within the 11 days of solar simulator exposure undertaken here. We show that the magnitude of a laboratory‐determined residual dose depends on the adopted bleaching protocol and cannot be used as a proxy for the dose that remains in the sample at the time of burial (remnant dose). Our data emphasize the importance of finding a balance between sufficient signal stability and a minimized contribution of a remnant dose when using pIR procedures for feldspar luminescence dating.  相似文献   
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