Distribution of Marine Palynomorphs in Surface Sediments, Prydz Bay, Antarctica

• Main Author: Storkey, Claire Andrea
• Other Authors: Hannah, Mike
• Format: Master Thesis
• Language: English
• Published: Victoria University of Wellington 2006
• Subjects: Palynomorph distribution; Glacial processes; Marine environment; Amery; Amery Ice Shelf; East Antarctica; Lambert Glacier; Prydz Bay; Prydz Channel; Antarc*; Antarctica; Ice Shelf
• Online Access: http://researcharchive.vuw.ac.nz/handle/10063/21

Prydz Bay Antarctica is an embayment situated at the ocean-ward end of the Lambert Glacier/Amery Ice Shelf complex East Antarctica. This study aims to document the palynological assemblages of 58 surface sediment samples from Prydz Bay, and to compare these assemblages with ancient palynomorph assemblages recovered from strata sampled by drilling projects in and around the bay. Since the early Oligocene, terrestrial and marine sediments from the Lambert Graben and the inner shelf areas in Prydz Bay have been the target of significant glacial erosion. Repeated ice shelf advances towards the edge of the continental shelf redistributed these sediments, reworking them into the outer shelf and Prydz Channel Fan. These areas consist mostly of reworked sediments, and grain size analysis shows that finer sediments are found in the deeper parts of the inner shelf and the deepest areas on the Prydz Channel Fan. Circulation within Prydz Bay is dominated by a clockwise rotating gyre which, together with coastal currents and ice berg ploughing modifies the sediments of the bay, resulting in the winnowing out of the finer component of the sediment. Glacial erosion and reworking of sediments has created four differing environments (Prydz Channel Fan, North Shelf, Mid Shelf and Coastal areas) in Prydz Bay which is reflected in the palynomorph distribution. Assemblages consist of Holocene palynomorphs recovered mostly from the Mid Shelf and Coastal areas and reworked palynomorphs recovered mostly from the North Shelf and Prydz Channel Fan. The percentage of gravel to marine palynomorph and pollen counts show a relationship which may reflect a similar source from glacially derived debris but the percentage of mud to marine palynomorph and pollen counts has no relationship. Reworked palynomorphs consist of Permian to Eocene spores and pollen and Eocene dinocysts which are part of the Transantarctic Flora. Holocene components are a varied assemblage of acritarchs, dinoflagellate cysts (dinocysts), prasinophyte algae, red algae and ...