Data/hora: 06/06/2024 02:47:16

Provedor de dados: 	5	
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	
Fonte: 	Copyright 2011 by the American Geophysical Union

info:eu-repo/semantics/openAccess

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