Clay and bulk mineralogy of ODP sites 119-745 and 119-746 from the Southern Ocean ...

• Main Authors: Ehrmann, Werner, Grobe, Hannes, Fütterer, Dieter K
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1991
• Subjects: Drilling/drill rig; Leg119; Joides Resolution; Ocean Drilling Program ODP; Antarc*; Antarctic; Antarctica; East Antarctica; Ice Shelves; Southern Ocean
• Online Access: https://dx.doi.org/10.1594/pangaea.587843; https://doi.pangaea.de/10.1594/PANGAEA.587843

The sediments recovered at ODP Sites 745 and 746 in the Australian-Antarctic Basin are characterized by cyclic facies changes between clayey diatom oozes and diatomaceous clays ranging in age from late Miocene (about 10 Ma) to Quaternary. The gravel and terrigenous sand content of the sediments is used as an indicator of the intensity of ice rafting through time. Maxima are recorded at 8.7-7.9, 6.6-6.0, 5.0-4.4, and 4.0-3.2 Ma. The maxima in more recent times are much less pronounced and occur at 2.4-1.6 and 1.4-1.0 Ma. All sand- and gravel-sized terrigenous sediment particles are of gneissic or granitic origin and originated from the East Antarctic continent. The maxima of ice rafting recorded at Sites 745 and 746 do not appear to represent local phenomena. Rather they document major advances and decays of the Antarctic ice shelves and glaciers and therefore represent events of great importance for the reconstruction of the paleoceanography of the Southern Ocean and the glacial history of Antarctica. In ... : Supplement to: Ehrmann, Werner; Grobe, Hannes; Fütterer, Dieter K (1991): Late Miocene to Holocene glacial history of east Antarctica revealed by sediments from sites 745 and 746. In: Barron, J; Larsen, B; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 119, 239-260 ...