Late Quaternary stratigraphy based on planktonic foraminifera off Senegal
Six soft sediment cores, up to and over 9 m in length, and additional surface samples were selected for study of their planktonic foraminifera to provide information on the Holocene and Pleistocene stratigraphy of the West African continental margin south of the present boundary of the Sahara. The m...
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Format: | Article in Journal/Newspaper |
Language: | English |
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Bornträger
1975
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Online Access: | https://oceanrep.geomar.de/id/eprint/56654/ https://oceanrep.geomar.de/id/eprint/56654/1/Pflaumann_U_1975_C.pdf |
Summary: | Six soft sediment cores, up to and over 9 m in length, and additional surface samples were selected for study of their planktonic foraminifera to provide information on the Holocene and Pleistocene stratigraphy of the West African continental margin south of the present boundary of the Sahara. The material was collected mainly by the German research vessel "Meteor" during Cruise 25 in 1971. One piston core has been selected from the material provided by the Trans-Atlantic Geotraverse project of thc U. S. National Oceanic and Atmospheric Administration (NOAA ship "Discoverer"). The residues larger than 160 microns were determined, counted and statistically evaluated (Fig. 11 ). Stratigraphical correlations with trans-Atlantic regions are given by the occurrence of Truncorotaloides hexagonus and Globorotalia tumida flexuosa which mark the last interglacial stage (Fig. 2). According to the climatic record the two deep-sea cores extend down to the V-zone, considered here as equivalent to the Mindel-Riss-interglacial time, as there are three distinctly warm and two cold periods indicated in the cores by planktonic foraminiferal faunas. Z-zone = Holocene is present in all cores, Y-zone = Würmian glacial can be divided into five sections, three cold and two warm stages; the X-zone can be divided into three warm stages, separated by two cool periods. The earliest warm stage is indicated to be the warmest one. There are excellent correlations to the Camp century ice core from Greenland, to the Mediterranean, to the Carribbean and to the tropical Atlantic as weil as to the Barbados stages (Fig. 27). The W-zone was correlated to the Riss-glacial. V-zone is a warm period, the upper limit of which being not sufficiently defined, which contains also some cool sections. Increasing sedimentation rates from the deep-sea to the upper slope reveal climatic and regional details in Holocene and Late Pleistocene history of the continental margin. These were based mainly on different parameters of planktonic foraminiferal ... |
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