气候变化领域集成服务门户(CCPortal): Evidence of high lateral variations of coda Q from local earthquakes in Western Iberia and its SW offshore area

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DOI	10.1016/j.tecto.2020.228564
	Evidence of high lateral variations of coda Q from local earthquakes in Western Iberia and its SW offshore area
	Vales D.; Havskov J.; Matias L.; Silva S.
发表日期	2020
ISSN	00401951
卷号	791
英文摘要	We compute coda-wave attenuation for the Western Iberia and, for the first time, for its SW offshore area. Western Iberia has been well covered by the growing number of permanent seismic stations during the last decade, providing a large dataset. Using this dataset along with offshore seismograms of local earthquakes recorded by temporary ocean-bottom seismometers, and adopting the single backscattering model, we estimate the coda Q at five frequency bands centred at 1, 2, 4, 8 and 16 Hz. Then, we calculate coda Q average values on a geographical grid, 0.5°x0.5° resolution, using regionalization and inversion techniques. We observe that the coda Q at 10 Hz varies from 1057 in the NW continental Iberia to 448 in the South-western offshore area, where there is no crust. Additionally, we find that the area with similar low coda Q value is located in the SE Iberia (Betic range). Therefore, our coda Q grid results exhibit higher values over the older and stable crust and lower values in the offshore margin or active tectonic regions. This suggests that the regional variation in coda Q is less sensitive to crustal thickness than to the tectonic activity in each area and crustal age. Furthermore, we discuss our coda Q results through a comparison with those from other regions in the world, where coda Q has been determined with the same parameters. Our work highlights the importance of coda Q studies as an effective tool to investigate detailed regional differences in seismic attenuation that may be relevant for earthquake seismic hazard and risk assessment studies. © 2020 Elsevier B.V.
关键词	Coda waves Crustal thickness Seismic attenuation SW Iberia margin Tectonics Western Iberia
英文关键词	Large dataset; Offshore oil well production; Risk assessment; Structural geology; Tectonics; Backscattering models; Inversion techniques; Lateral variations; Ocean bottom seismometer; Regional differences; Regional variation; Seismic attenuation; Seismic hazard and risk assessments; Earthquakes; backscatter; coda; data set; earthquake event; ocean bottom seismometer; Q factor; seismic attenuation; seismogram; wave attenuation; Iberian Peninsula
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207890
作者单位	Instituto Português do Mar e da Atmosfera, Rua C do Aeroporto, Lisboa, 1749-077, Portugal; Department of Earth Science, University of Bergen, Allegaten 41, Bergen, 5007, Norway; Instituto Dom Luiz, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Ed. C8, Lisbon, 1749-016, Portugal; Centre of Marine Sciences, Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Portugal
推荐引用方式 GB/T 7714	Vales D.,Havskov J.,Matias L.,et al. Evidence of high lateral variations of coda Q from local earthquakes in Western Iberia and its SW offshore area[J],2020,791.
APA	Vales D.,Havskov J.,Matias L.,&Silva S..(2020).Evidence of high lateral variations of coda Q from local earthquakes in Western Iberia and its SW offshore area.Tectonophysics,791.
MLA	Vales D.,et al."Evidence of high lateral variations of coda Q from local earthquakes in Western Iberia and its SW offshore area".Tectonophysics 791(2020).