Grain shape of sediment from the Weddell Sea ...

• Main Authors: Smith, C H, O'Connell, Suzanne B
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1990
• Subjects: Drilling/drill rig; Leg113; Joides Resolution; Ocean Drilling Program ODP; Antarc*; Antarctica; Weddell Sea
• Online Access: https://dx.doi.org/10.1594/pangaea.753898; https://doi.pangaea.de/10.1594/PANGAEA.753898

Very fine quartz sand was examined from Paleogene and Neogene sediments of ODP Sites 693, 694, 695, 696, and 697 to determine their grain roundness using Fourier analysis and SEM surface texture characteristics. The objective of this study was to identify grain roundness and surface texture characteristics unique to East (Site 693) and West (Sites 695, 696, and 697) Antarctica and to glacial regimes. Once identified, these distinguishing features could then be used to determine changes in source area and glacial conditions in the central Weddell Sea Basin (Site 694).Three end members of very fine quartz sand are recognized in the Oligocene to Pleistocene sediments of the Weddell Sea: angular, rounded, and intermediate. End member 1 (angular) consists of extremely angular grains with numerous fracture textures. Previous investigations suggested that these sands are derived from crystalline rocks that fractured during formation or deformation and/or were exposed to weathering by ice. In this study, however, ... : Supplement to: Smith, C H; O'Connell, Suzanne B (1990): Provenance and glacial history of very fine quartz sand from the Weddell Sea, Antarctica. In: Barker, PF; Kennett, JP; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 113, 89-109 ...