Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Registro completo
Provedor de dados:  ArchiMer
País:  France
Título:  Isolating climatic and paleomagnetic imbricated signals in two marine cores using principal component analysis
Autores:  Valet, Jean-pierre
Moreno, Eva
Bassinot, Franck
Johannes, Lola
Dewilde, Fabien
Bastos, Tiago
Lefort, Apolline
Venec-peyre, Marie-therese
Data:  2011-08
Ano:  2011
Palavras-chave:  Magnetization
Paleointensity
Paleomagnetism
Sediments
Resumo:  High resolution measurements of climatic and magnetic parameters have been performed on two cores from the eastern China Sea and the western Caroline Basin. On both cores, magnetic parameters show a strong imprint of climatic changes but the absence of relationship between the inclination and the bulk density indicates that the directional changes do not depend on lithology. A weak 100 ka cycle is present in the China sea inclination variations, but this period is not in phase with the orbital eccentricity and thus not relevant. All normalization parameters yielded similar estimates of relative paleointensity (RPI), but we have noticed the persistence of climatic components in the signal. Principal Component Analysis (PCA) applied to different parameters related to climate, lithology and paleointensity has allowed to extract a "clean" magnetic signal that we refer as "principal component of paleointensity (PCP)" which is in better agreement with the Sint-2000 composite curve and provides a reliable record of relative paleointensity. The presence of climatic frequencies in RPIs most likely reflects the influence of lithology on the response of magnetization to field intensity. We suggest that PCA analysis can be very useful to approach these problems. Not only can the calculation separate overlapping climatic and magnetic signals, but it indicates what confidence should be given to the data. Incidentally, the present results emphasize the importance of carrying out detailed paleoclimatic analyses along with paleointensity studies.
Tipo:  Text
Idioma:  Inglês
Identificador:  https://archimer.ifremer.fr/doc/00227/33818/32481.pdf

DOI:10.1029/2011GC003697

https://archimer.ifremer.fr/doc/00227/33818/
Editor:  Amer Geophysical Union
Formato:  application/pdf
Fonte:  Geochemistry Geophysics Geosystems (1525-2027) (Amer Geophysical Union), 2011-08 , Vol. 12 , N. 8 , P. Q08012
Direitos:  Copyright 2011 by the American Geophysical Union

info:eu-repo/semantics/openAccess

restricted use
Fechar
 

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

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional