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  • Abstract: The ratio between the clay minerals kaolinite and chlorite has been investigated in high resolution in a late Quaternary sediment core from the central Aegean Sea. The record spans the last ca. 105 ka. The kaolinite/chlorite ratio was used to reconstruct the fine-grained aeolian dust influx from the North African deserts, mainly derived from desiccated lake depressions. It therewith can be used as a proxy for wind activity, aridity and vegetation cover in the source area. The data document three major humid phases in North Africa bracketing the formation of sapropel layers S4, S3 and S1. They occur at >105-95 ka, 83.5-72 ka and 14-2 ka. The first two phases are characterised by relatively abrupt lower and upper boundaries suggesting a non-linear response of vegetation to precipitation, with critical hydrological thresholds. In contrast, the onset and termination of the last humid period were more gradual. Highest kaolinite/chlorite ratios indicating strongest aeolian transport and aridity occur during Marine Isotope Stage (MIS) 5b, at ca. 95-84 ka. The long-term decrease in kaolinite/chlorite ratios during the last glacial period indicates a gradual decline of deflatable lake sediments in the source areas. Category: geoscientificInformation Source: Supplement to: Ehrmann, Werner; Seidel, Martin; Schmiedl, Gerhard (2013): Dynamics of Late Quaternary North African humid periods documented in the clay mineral record of central Aegean Sea sediments. Global and Planetary Change, 107, 186-195, https://doi.org/10.1016/j.gloplacha.2013.05.010 Supplemental Information: Not Availble Coverage: EVENT LABEL: (GeoTü SL143) * LATITUDE: 38.261830 * LONGITUDE: 25.103170 * ELEVATION: -665.0 m * LOCATION: Aegean Sea * DEVICE: Gravity corer (Kiel type)
    Data Types:
    • Tabular Data
    • Dataset
  • Response of deep-sea benthic foraminifera to Late Quaternary climate changes, southeast Indian Ocean, offshore Western Australia
    Data Types:
    • Tabular Data
    • Dataset
  • cores... core... late... Sediment... Quaternary.
    Data Types:
    • Collection
    • Tabular Data
    • Text
  • Response of deep-sea benthic foraminifera to Late Quaternary climate changes, southeast Indian Ocean, offshore Western Australia
    Data Types:
    • Tabular Data
    • Dataset
  • Quaternary... Late... sediments... sediment... Sediments
    Data Types:
    • Collection
    • Tabular Data
    • Text
  • Pre-Quaternary spores... Pre-Quaternary pollen... DEPTH, sediment/rock
    Data Types:
    • Tabular Data
    • Dataset
  • Late Quaternary... DEPTH, sediment/rock
    Data Types:
    • Tabular Data
  • Abstract: An astronomically tuned late Quaternary planktic foraminiferal delta18O record of Site MD972142 (12°41.33'N, 119°27.90'E; 1557 m water depth) in the southeastern South China Sea was established. The difference in delta18O between MD972142 and ODP792 of the Sulu Sea is regarded as a maritime proxy of the summer monsoon intensity over the South China Sea and Southeast Asia. The profile of this maritime proxy matches well with the summer monsoon index obtained from the terrestrial record of Louchuan, central Chinese Loess Plateau. The amplified planktic delta18O signals of the South China Sea relative to the Sulu Sea record are partly caused by the changing intensities of the East Asian Monsoons at the glacial-interglacial time-scale throughout the late Quaternary. Category: geoscientificInformation Source: Supplement to: Wei, Kuo-Yen; Chiu, Tzu-Chien; Chen, Yue-Gau (2003): Toward establishing a maritime proxy record of the East Asian summer monsoons for the late Quaternary. Marine Geology, 201(1-3), 67-79, https://doi.org/10.1016/S0025-3227(03)00209-3 Supplemental Information: Not Availble Coverage: EVENT LABEL: (MD972142) * LATITUDE: 12.685000 * LONGITUDE: 119.465000 * Recovery: 35.91 m * CAMPAIGN: MD106 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Calypso Corer
    Data Types:
    • Tabular Data
    • Dataset
  • Response of deep-sea benthic foraminifera to Late Quaternary climate changes, southeast Indian Ocean, offshore Western Australia
    Data Types:
    • Tabular Data
    • Dataset
  • Response of deep-sea benthic foraminifera to Late Quaternary climate changes, southeast Indian Ocean, offshore Western Australia
    Data Types:
    • Tabular Data
    • Dataset