Occurrence of microtextures recorded from quartz sand grains of ODP Hole 178-1101A (Table 1) ...

• Main Authors: Cowan, Ellen A, Hillenbrand, Claus-Dieter, Hassler, Lauren E, Ake, Matthew T
• Format: Dataset
• Language: English
• Published: PANGAEA 2008
• Subjects: DEPTH, sediment/rock; AGE; Sample code/label; Roundness; Quartz, surface texture; Quartz; Comment; Drilling/drill rig; DSDP/ODP/IODP sample designation; Scanning electron microscope SEM; Counting 250-2000 µm fraction; Leg178; Joides Resolution; Ocean Drilling Program ODP; Antarc*; Antarctic; Antarctic Peninsula; Planktonic foraminifera; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.706581; https://doi.pangaea.de/10.1594/PANGAEA.706581

Sediment drifts on the continental rise are located proximal to the western side of the Antarctic Peninsula and recorded changes in glacial volume and thermal regime over the last ca. 15 m.y. At Ocean Drilling Program (ODP) Site 1101 (Leg 178), which recovered sediments back to 3.1 Ma, glacial-interglacial cyclicity was identified based on the biogenic component and sedimentary structures observed in X-radiographs, magnetic susceptibility and lithofacies descriptions. Glacial intervals are dominated by fine-grained laminated mud and interglacial units consist of bioturbated muds enriched in biogenic components. From 2.2 to 0.76 Ma, planktonic foraminifera and calcareous nannofossils dominate in the interglacials suggesting a shift of the Antarctic Polar Front (APF) to the south near the drifts. Prior to 2.2 Ma, cyclicity cannot be identified and diatoms dominate the biogenic component and high percent opal suggests warmer conditions south of the APF and reduced sea ice over the drifts. Analyses of the ... : The composite depth scales and age models of Barker (2002, doi:10.2973/odp.proc.sr.178.219.2001) were used to develop a chronology. The age of each sample collected from Sites 1101 was computed by linear interpolation between magnetostratigraphic datums from Acton et al. (2002, doi:10.2973/odp.proc.sr.178.235.2002). ...