| Diatoms' opaline cell walls, called frustules, are readily preserved in a variety of geological settings. As such, they are utilized extensively in paleoecology, paleoceanography, and paleoclimatology, especially in the Southern Ocean's opal belt. However, taphonomic effects on opal export and recycling are rarely quantified in paleoecological studies. This study serves to develop and apply quantitative taphonomic proxies, generated via laboratory dissolution of diatom frustules. Scanning electron microscopy was used to measure dissolution-induced morphological change as a proxy of dissolution.;These proxies are applied to core PS58/254 from the Amundsen Sea near the Pine Island Glacier, which drains a large proportion of the West Antarctic Ice Sheet. A change in both diatom preservation and biogenic barite accumulation between Marine Isotope Stages 7 and 8 represents a decrease in advection of deep water onto the shelf, creating a relatively more stable Pine Island Glacier. Next, diatom dissolution proxies are applied to core NBP0101-JPC24, which contains a Holocene record of sea-ice and climatctic conditions from Prydz Bay. Inception of the Prydz Bay gyre is seen to increase diatom dissolution. Diatom preservation and sediment facies analysis are used to identify three styles of glacial advance and one well preserved glacial retreat in the ANDRILL AND-1B drill core. In addition to taphonomic studies, a comparison of diatom distributions in surface sediment and stratigraphically averaged surface samples collected across 30 years from the Mertz Glacier polynya is conducted. This study demonstrates that increased deep-water formation in the polynya has resulted in a more depauperate the diatom record. Finally, an updated and simplified method for diatom slide generation is presented. |
