Seismic hazard for the Central Group of the Azores Islands
Seismic hazard for the Central Group of the Azores Islands
复制标题
亚速尔群岛中部群的地震危险
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
V. Forjaz
中科院分区：
文献类型：
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作者：
A. Carvalho;M. L. Sousa;C. Oliveira;A. Campos;J. Nunes;V. Forjaz
已为亚速尔群岛编制了一般地震危险图，或利用该区域最新的地震资料，包括修订1522-1998年期间的地震目录，为中央群岛各岛屿编制了地震危险图。使用了两种不同的方法：（一）标准震源模型和（二）基于空间平滑地震活动性的半分区震源模型，其中不需要对震源进行划界。初步数据指出，在中央群岛以西的一个地区以及在特塞拉和圣米格尔群岛之间的一个地区获得了高PGA值。对一些县的灾害进行了分解评估，结果以震级和距离的平均值和模态值表示，表明所有县的灾害主要来自近距离地震，而不是非常严重的地震。
Probabilistic seismic hazards maps have been prepared either for the archipelago of the Azores in general terms, or for the islands of the Central Group using updated seismic information for the region, including a revision of the earthquake catalogue for the period 1522-1998. Two different approaches were used: (i) a standard seismic source model and (ii) a semi-zonified source model based on spatially smoothed seismicity where no delineation of seismic sources is needed. Preliminary data point out that high PGA values were obtained for an area located to the west of the Central Group and for an area between Terceira and the Sao Miguel Islands. Deaggregation of hazard for some counties was evaluated and results are presented in terms of mean and modal values of magnitude and distance, showing that the main contributions to hazard in all counties are from close-in and not very severe earthquakes.