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	Provedor de dados 5 (2) Autor Von Dobeneck, Tilo (2) Bickert, Torsten (1) Dekkers, Mark J. (1) Diekmann, Bernhard (1) Frederichs, Thomas (1) Gersonde, Rainer (1) Just, Janna (1) Kasten, Sabine (1) Korff, Lucia (1) Kuhn, Gerhard (1) Van Hoesel, Annelies (1) Mais... Palavra-chave Abyssal sediments (1) Carbon trapping (1) Environmental magnetism (1) IRM end-member modeling (1) Magnetite dissolution (1) Magnetotactic bacteria (1) Mid-Pleistocene transition (1) NW Africa (1) Northwest Pacific Ocean (1) Paleoclimate (1) Tephra layers (1) Terrigenous input (1) Mais... Tipo do documento Text (2) Ano 2016 (1) 2012 (1) País France (2) Idioma Inglês (2)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 2 Primeira ... 1 ... Última Signatures and significance of aeolian, fluvial, bacterial and diagenetic magnetic mineral fractions in Late Quaternary marine sediments off Gambia, NW Africa 5 Just, Janna; Dekkers, Mark J.; Von Dobeneck, Tilo; Van Hoesel, Annelies; Bickert, Torsten. Two gravity cores retrieved off NW Africa at the border of arid and subtropical environments (GeoB 13602-1 and GeoB 13601-4) were analyzed to extract records of Late Quaternary climate change and sediment export. We apply end-member (EM) unmixing to 350 acquisition curves of isothermal remanent magnetization (IRM). Our approach enables to discriminate rock magnetic signatures of aeolian and fluvial material, to determine biomineralization and reductive diagenesis. Based on the occurrence of pedogenically formed magnetic minerals in the fluvial and aeolian EMs, we can infer that goethite formed in favor to hematite in more humid climate zones. The diagenetic EM dominates in the lower parts of the cores and within a thin near-surface layer probably... Tipo: Text Palavras-chave: IRM end-member modeling; NW Africa; Environmental magnetism; Magnetotactic bacteria; Paleoclimate; Terrigenous input. Ano: 2012 URL: https://archimer.ifremer.fr/doc/00265/37617/36987.pdf Cyclic magnetite dissolution in Pleistocene sediments of the abyssal northwest Pacific Ocean: Evidence for glacial oxygen depletion and carbon trapping 5 Korff, Lucia; Von Dobeneck, Tilo; Frederichs, Thomas; Kasten, Sabine; Kuhn, Gerhard; Gersonde, Rainer; Diekmann, Bernhard. The carbonate-free abyss of the North Pacific defies most paleoceanographic proxy methods and hence remains a blank spot in ocean and climate history. Paleomagnetic and rock magnetic, geochemical, and sedimentological methods were combined to date and analyze seven middle to late Pleistocene northwest Pacific sediment cores from water depths of 5100 to 5700m. Besides largely coherent tephra layers, the most striking features of these records are nearly magnetite-free zones corresponding to glacial marine isotope stages (MISs) 22, 12, 10, 8, 6, and 2. Magnetite depletion is correlated with organic carbon and quartz content and anticorrelated with biogenic barite and opal content. Within interglacial sections and mid-Pleistocene transition glacial stages MIS... Tipo: Text Palavras-chave: Northwest Pacific Ocean; Carbon trapping; Magnetite dissolution; Mid-Pleistocene transition; Tephra layers; Abyssal sediments. Ano: 2016 URL: https://archimer.ifremer.fr/doc/00421/53247/54725.pdf Registros recuperados: 2 Primeira ... 1 ... Última

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