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| Dobrynina, A. A.; Sankov, V. A.; Deverchere, Jacques; Chechelnitsky, V. V.. |
| Attenuation of seismic waves in the crust and the upper mantle has been studied in three global rift systems: the Baikal rift system (Eurasia), the North Tanzanian divergence zone (Africa) and the Basin and Range Province (North America). Using the records of direct and coda waves of regional earthquakes, the single scattering theory [Aki, Chouet, 1975], the hybrid model from [Zeng, 1991] and the approach described in [Wennerberg, 1993], we estimated the seismic quality factor (QC), frequency parameter (n), attenuation coefficient (delta), and total attenuation (QT). In addition, we evaluated the contributions of two components into total attenuation: intrinsic attenuation (Qi), and scattering attenuation (Qsc). Values of QC are strongly dependent on the... |
| Tipo: Text |
Palavras-chave: Baikal rift system; East African rift system; North American Basin and Range Province; Attenuation of seismic waves; Seismic quality factor; Seismicity; Coda waves; Intrinsic attenuation; Scattering attenuation; Heat flow. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00638/75049/75658.pdf |
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| Courgeon, Simon; Jorry, Stephan; Camoin, G. F.; Boudagher-fadel, M. K.; Jouet, Gwenael; Revillon, Sidonie; Bachelery, P.; Pelleter, Ewan; Borgomano, J.; Poli, E.; Droxler, A. W.. |
| Although long-term evolutions of isolated shallow-water carbonate platforms and demise episodes leading to guyot formation have been the subject of numerous studies during the last decades, their driving processes are still the subject of active debates. The Mozambique Channel (SW Indian Ocean) is characterized by several flat-topped seamounts ranging from 11°S to 21°S in latitudes. Based on a comprehensive geomorphologic study and on dredged samples analysis, we show that these features correspond to tropical isolated shallow-water carbonate platforms. Coupling strontium isotopy and foraminifera biostratigraphy, well-constrained chronostratigraphy results indicate that shallow-water carbonate production started in the Mozambique Channel during distinct... |
| Tipo: Text |
Palavras-chave: Carbonate platform; Drowning; Cenozoic; Mozambique Channel; East African rift system. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00347/45827/46634.pdf |
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