Sabiia Seb
        Busca avançada

Botão Atualizar

Botão Atualizar

Registro completo
Provedor de dados:  ArchiMer
País:  France
Título:  Holocene Event Record of Aysén Fjord (Chilean Patagonia): an Interplay of Volcanic Eruptions, Crustal and Megathrust Earthquakes
Autores:  Wils, Katleen
Van Daele, Maarten
Lastras, Galderic
Kissel, Catherine
Lamy, Frank
Siani, Giuseppe
Data:  2018-01
Ano:  2018
Palavras-chave:  Paleoseismology
Seismic stratigraphy
Resumo:  In the first months of 2007, the Aysén region in southern Chile was affected by a crustal seismic swarm. Its largest earthquake (Mw 6.2) occurred in April and had its epicenter in Aysén Fjord. Seismic intensities became so high that hundreds of onshore mass movements were triggered, several of which entered into the fjord, resulting in mass transport deposits (MTDs) preserved at the fjord bottom. Here we present a Holocene record of paleo-earthquakes in the previously unstudied Patagonian fjordland based on MTD stratigraphy. High-resolution seismic data retrieved using two different seismic systems (sparker and TOPAS) reveal multiple older MTDs on different stratigraphic levels. Correlation of the seismic stratigraphy with sedimentological data obtained from a long Calypso core (MD07-3117) allows conclusion on the seismic origin of these deposits. Additionally, radiocarbon dating permits constructing an age model, validated by tephrochronology, providing an age for the different MTD levels. We thus present a highly detailed paleoseismological history of the Aysén region, including at least six major Holocene earthquakes, one of which is likely related to a known megathrust earthquake. Other earthquakes are related to activity of the Liquiñe-Ofqui Fault Zone (LOFZ), forming the main source of seismic hazard in the area. We can infer a general average recurrence time for LOFZ earthquakes of ~2,100 years in the vicinity of Aysén Fjord with clustered events during the early and late Holocene. Finally, we argue that cascading events (causal link between volcanic and seismic events) may be a frequent phenomenon along the LOFZ.
Tipo:  Text
Idioma:  Inglês

Editor:  Amer Geophysical Union
Formato:  application/pdf
Fonte:  Journal Of Geophysical Research-solid Earth (2169-9313) (Amer Geophysical Union), 2018-01 , Vol. 123 , N. 1 , P. 324-343
Direitos:  2017. American Geophysical Union. All Rights Reserved.


restricted use

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC:

Valid HTML 4.01 Transitional