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  • Journal of Quaternary Science
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  • Abstract: The pollen record of three marine late Quaternary cores off Senegal shows a juxtaposition of Mediterranean, Northern Saharan, Central Saharan elements, which are considered transported by the trade winds from a winter-rainfall area, and Sahelian, Soudanese, Soudano-Guinean elements, considered transported both by winds and mostly by the Senegal River, and coming from the monsoonal, summer tropical rainfall area of southern West Africa. Littoral vegetation is either the edaphically dry and saline Chenopodiaceae from sebkhas at the time of the main regression, or the warm tropical humid mangrove with Rhizophora during the humid optimum period. Four stratigraphic zones reflect, from basis to top: Zone 4. A semi-arid period with a balanced pollen input. Zone 3. A very arid period with the disappearance of monsoonal pollen, probably from the disappearance of the Senegal River, a very saline littoral plain with Chenopodiaceae, a larger input of northern Saharan pollen from intensified trade winds. Zone 2. A quite humid period, much more so than today, very suddenly established, with a northward extension of the monsoonal areas, a rich littoral mangrove, and weakening of the trade winds. Zone l. A slow and steady evolution toward the present semi-humid conditions with regression of the mangrove, and of the monsoonal areas toward the south. Tentative datations and correlations with the Tchad area suggested: zone 4: 22,500 to 19,000 years BP; zone 3: 19,000 to 12,500 years BP; zone 2: 12,500 to 5,500 years BP; zone 1: 5,500 years BP to top of core. Dinoflagellate cysts display a tropical assemblage with mostly estuarine neritic elements and also a weak oceanic component, mostly in the lower slope core 47. Cosmopolitan taxa dominate the assemblage and only a few species point to more specialized environments. Quantitative variations of the assemblage are the basis of stratigraphy which is not similar to the pollen stratigraphy, and an inshore-outshore gradient has to be taken into account to correlate the three cores. Category: geoscientificInformation Source: Supplement to: Rossignol-Strick, Martine; Duzer, Daniele (1979): Late Quaternary pollen and dinoflagellate cysts in marine cores off West Africa. Meteor Forschungsergebnisse, Deutsche Forschungsgemeinschaft, Reihe C Geologie und Geophysik, Gebrüder Bornträger, Berlin, Stuttgart, C30, 1-14 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 15.443333 * LONGITUDE: -17.306667 * DATE/TIME: 1971-01-01T00:00:00 * ELEVATION: -625.0 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * METHOD|DEVICE: Kasten corer EVENT LABEL: * LATITUDE: 15.480000 * LONGITUDE: -17.360000 * DATE/TIME: 1971-11-17T00:00:00 * ELEVATION: -945.0 m * Recovery: 5.5 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * METHOD|DEVICE: Kasten corer EVENT LABEL: * LATITUDE: 15.825000 * LONGITUDE: -17.861667 * DATE/TIME: 1971-11-17T00:00:00 * ELEVATION: -2576.0 m * Recovery: 6 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * METHOD|DEVICE: Kasten corer
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  • A dataset containing 56 species occurrences available in GBIF matching the query: DatasetKey: (Table 4) Principal component analysis, paleotemperatures and distribution of infaunal benthic foraminifera in Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean. The dataset includes 56 records from 1 constituent datasets: 56 records from (Table 4) Principal component analysis, paleotemperatures and distribution of infaunal benthic foraminifera in Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean. Data from some individual datasets included in this download may be licensed under less restrictive terms.
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  • A dataset containing 358 species occurrences available in GBIF matching the query: DatasetKey: (Appendix 3, Table 4) Relative abundances of benthic foraminifera in Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean. The dataset includes 358 records from 1 constituent datasets: 358 records from (Appendix 3, Table 4) Relative abundances of benthic foraminifera in Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean. Data from some individual datasets included in this download may be licensed under less restrictive terms.
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  • A dataset containing 301 species occurrences available in GBIF matching the query: DatasetKey: (Appendix 4, Table 4) Relative abundances of benthic foraminifera in Late Quaternary sediments of core RC09-150 in the southeast Indian Ocean. The dataset includes 301 records from 1 constituent datasets: 301 records from (Appendix 4, Table 4) Relative abundances of benthic foraminifera in Late Quaternary sediments of core RC09-150 in the southeast Indian Ocean. Data from some individual datasets included in this download may be licensed under less restrictive terms.
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  • A dataset containing 51 species occurrences available in GBIF matching the query: DatasetKey: (Table 4) Principal component analysis, paleotemperatures and distribution of infaunal benthic foraminifera in Late Quaternary sediments of core RC09-150 in the southeast Indian Ocean. The dataset includes 51 records from 1 constituent datasets: 51 records from (Table 4) Principal component analysis, paleotemperatures and distribution of infaunal benthic foraminifera in Late Quaternary sediments of core RC09-150 in the southeast Indian Ocean. Data from some individual datasets included in this download may be licensed under less restrictive terms.
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  • Data used for constructing the age model for core GeoTü SL143. ... Location of the investigated sediment core GeoTü SL143 in the central Aegean Sea and the most important recent sediment source areas, transport processes and transport paths for the main clay mineral groups (after Ehrmann et al., 2007a, following Venkatarathnam and Ryan, 1971; Foucault and Mélières, 2000). Black arrows indicate the surface circulation (after Pickard and Emery, 1990; Aksu et al., 1995). The locations of cores MS27PT and GeoTü SL123 mentioned in the text are also indicated. The histograms indicate the generalised clay mineral composition of sediments delivered by NW and E Aegean Rivers (after Ehrmann et al., 2007a), the Nile River (after Hamann et al., 2009) and of Saharan dust in the eastern Mediterranean (after Chester et al., 1977). ... Combination of (A) the June insolation at 65°N, (B) the Nile sediment discharge deduced from core MS27PT (Revel et al., 2010; Caley et al., 2011), (C) the kaolinite/chlorite record in sediment core GeoTü SL123 from the southernmost Aegean Sea (Ehrmann et al., 2007b), and (D) the kaolinite/chlorite record in sediment core GeoTü SL143 from the central Aegean Sea. AHP: African humid periods, S sapropels in SL143, Y tephra layers, MIS=Marine Isotope Stages. ... Age/depth plot and kaolinite/chlorite peak heights ratios in sediments of core GeoTü SL143, central Aegean Sea, combined with the occurrences of tephra layers (Y2, Y5) and sapropel layers (S1, S3, S4) within the sequence. ... Late Quaternary
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  • Mineralogy of volcanic ash layers in sediments of the Okhotsk Sea (fraction 0.1–0.05 mm) ... LU stratigraphy in the Okhotsk Sea cores ... Okhotsk Sea core location and references ... Percentage of individual sediment fractions in cores V34-98 and 936 (lower panel) and the coefficient of correlation between MS and the content of these fractions (upper panel). The dotted and broken lines denote a minimal significant correlation coefficient at the 95% level of confidence for cores V34-98 and 936, respectively. Clay and silt are dominant in the sediments of both cores. There are positive correlations between MS and the silt–sand size fraction for both cores. In core 936, the correlation coefficient is larger for the coarse silt and very fine sand fractions than for fine–medium sand. In core V34-98 sediments, which are influenced by volcanic input, the MS-grain size correlations are reversed in comparison with core 936. ... Electron microprobe analyses of silic glassy tephra recovered at sediment cores ... sediment
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  • Late Quaternary variations in the concentrations of smectite, illite, kaolinite, chlorite (3-point-running means) and the linear sedimentation rate (LSR, in cm/ka) in core GeoTü SL112. Dark grey bar marks sapropel layer S1; light grey bars show Heinrich Events H1 and H2. The solar insolation in July at 15°N (W/m2), the abundance of terrigenous matter in core 74KL from the western Arabian Sea (Sirocko et al., 1996; 14°19.26′N, 57°20.82′E) and the sea-surface temperature record of core MD79257 from the Mozambique Channel, western Indian Ocean (Bard et al., 1997; 20°24′S, 36°29′E) are shown for comparison. African Humid Period marked after deMenocal et al. (2000a). Arrows at the top indicate 14C dates used for constructing the age model (Table 2), YD: Younger Dryas, B–A: Bølling–Allerød, LGM: last glacial maximum. ... (a) Map of the southeastern Levantine Sea and adjacent areas with location of sediment core GeoTü SL112. The distribution of the main clay mineral groups smectite (sm), illite (ill), kaolinite (kao), chlorite (chl) and palygorskite (paly) in recent dust samples (arrows) is shown (various sources, Table 1). For exact location of samples II.7 and II.8 see Table 1. Present-day sea-surface circulation is represented by white elongated arrows (Pinardi and Masetti, 2000), 100-m depth contours are given. (b) Distribution of the main clay mineral smectite (sm), groups illite (ill), kaolinite (kao) and chlorite (chl) in marine surface samples (asterisks) and recent river/wadi samples (arrows). The data have been compiled from various sources (see Table 1). ... Ternary diagram showing the clay mineral composition of the late Quaternary sediments of core GeoTü SL112, subdivided into the glacial interval (41 samples), the African Humid Period (44 samples) and the late Holocene (48 samples). The clusters of the modern clay mineral assemblages in the southeastern Levantine Sea region are reproduced from Figure 2 for comparison. II Saharan Dust Assemblage, III Near East Assemblage, V Egyptian Wadi Assemblage, VI Nile Assemblage, VII SE Levantine Sea Assemblage. The fields of the Northern Dust Assemblage (I) and the Sinai Assemblage (IV) plot outside the chosen sector. ... Compilation of published clay mineral data from river channel and wadi surface sediments, dust samples and marine surface sediments in the southeastern Levantine Sea and the adjacent mainland ... Data used for constructing the age model for the investigated core GeoTü SL112 ... Late Quaternary
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  • Sediment chemical analysis of the core Xinias 1. ... Preliminary reconstruction of past lake-level changes in Lake Xinias, based on the lithology of the single sediment core sampled by Bottema (1979). ... Late Quaternary lake-level changes... Department of Quaternary Geology, Lund university, Tornavägen 13, S-22363 Lund, Sweden... Ostracods in selected samples of the early Holocene aragonitic (samples 1 and 2) and calcitic (samples 3 and 4) sediment in core Xinias 1a ... sediment stratigraphy... Topographic map of the past Lake Xinias, showing the location of the studied transect of sediment cores. The shoreline before the recent drainage is indicated by broken line. ... Correlation of the cores Xinias 1–5 in the stratigraphical transect and the separate core Xinias 6.
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