Clay mineralogy of sediment cores from the South Atlantic and the Adjoining Southern Ocean, supplement to: Diekmann, Bernhard; Petschick, Rainer; Gingele, Franz; Fütterer, Dieter K; Abelmann, Andrea; Brathauer, Uta; Gersonde, Rainer; Mackensen, Andreas (1996): Clay mineral fluctuations in Late Quaternary sediments of the Southeastern South Atlantic: implications for past changes of deep water advection. In: Wefer, G; Berger, W H; Siedler, G & Webb, D (eds.), The South Atlantic: Present and Past Circulation. Springer-Verlag, Berlin, 118, 621-644

In the South Atlantic and adjoining Southern Ocean the kaolinite/chlorite-ratio in Late Quaternary sediments are an alternative deep water proxy to benthic foraminiferal proxies and carbonate preservation indices that is even suitable in regions with poor carbonate preservation. This paper shows the...

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Bibliographic Details
Main Authors: Diekmann, Bernhard, Petschick, Rainer, Gingele, Franz, Fütterer, Dieter K, Abelmann, Andrea, Brathauer, Uta, Gersonde, Rainer, Mackensen, Andreas
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA - Data Publisher for Earth & Environmental Science 1996
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Online Access:https://dx.doi.org/10.1594/pangaea.728694
https://doi.pangaea.de/10.1594/PANGAEA.728694
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Summary:In the South Atlantic and adjoining Southern Ocean the kaolinite/chlorite-ratio in Late Quaternary sediments are an alternative deep water proxy to benthic foraminiferal proxies and carbonate preservation indices that is even suitable in regions with poor carbonate preservation. This paper shows the relationship between modern abyssal circulation and the kaolinite/chloriteratio and presents reconstructions of deep and bottom water advection based on the kaolinite/chlorite proxy. We also discuss the limitations and future perspectives of the kaolinite/chlorite proxy. Latitudinal and water depth-related patterns of the kaolinite/chlorite-ratio in surface sediments correspond to the modern deep and bottom water mass distribution. Kaolinite originates from lowlatitudes and traces North Atlantic Deep Water (northern-source deep water) advection to the south. Chlorite from the southern high-latitudes is exported via northward advecting Antarctic Bottom Water and Circumpolar Deep Water (southern-source deep and bottom water). Deep-sea sedimentation in regions underlying the Antarctic Circumpolar Current was current-dominated throughout the Late Quaternary. Temporal variations of the kaolinite/chlorite-ratio in response to glacial-interglacial cycles reflect changing deep water mass configurations, suggesting a shallowing and northward retreat of northern-source deep water and accordingly wider expansion of southernsource deep and bottom water masses during glacial times relative to interglacial times. Submarine topography influenced the spatial and temporal patterns of deep water mass distribution.