- 1Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Department of Deep-sea Geophysics and Resources, China (huangxx@idsse.ac.cn; xiaozijian21@mails.ucas.edu.cn; yangx@idsse.ac.cn)
- 2University of Chinese Academy of Sciences, China (xiaozijian21@mails.ucas.edu.cn)
Abstract: The deepest area of the continental shelf is located at the Drygalski Trough, western Ross Sea, with a water depth over 1,100 m. Sedimentation in Drygalski Trough is mainly controlled by the past East Antarctic Ice Sheet (EAIS). Previous studies discussed the sediment facies and sedimentary environments, but the analysis of sediment source provenance is poor, transport dynamics and post-transport processes are not clearly, the correspondence between sedimentary events and paleoclimate changes still needs to be explored. We analyzed the grain size, XRF, biogenic silica, and isotope dating to obtain the information of the composition and access the sedimentation mechanism from the two new gravity cores collected in the Drygalski Trough by Chinese Antarctic Expedition. The preliminary results indicate that the sediments are characterised by coarse diamictons with low biological productivity and stronger hydrodynamics during the glacial, and by clay and silt deposits with increased biological productivity and lower hydrodynamics during the interglacial, and what appears to be a renewed trend toward stronger hydrodynamics in the present. Several thin interbedded deposits on the gravity core contain high amounts of ice rafted debris (IRD), presumably controlled by formation of the polynya and density shelf water discharge. The adjacent cores support that Drygalski trough had received subglacial sediments since 20 ka. The aim of this study is to reveal the sediment events under the complicated palaeoceanographic conditions and ice sheet-ocean interaction based on the changes in biological productivity and the formation of polynya since the ending of Last Glacial Maximum. The reconstruction of the evolution of the depositional environment in the Drygalski trough, western Ross Sea, analyzing the past glacial activities and history of Paleocean ventilation provides key information for predicting the impacts of future glacier changes and improving the accuracy of glacier-ocean models.
Key Words: Drygalski Trough; Ross Sea; marine sedimentology; ice sheet dynamics; sediment cores; palaeoceanographic evolution; Antarctica.
How to cite: Xiao, Z., Huang, X., and Yang, X.: Tracing palaeoceanographic archives of ice sheet-ocean interaction of the western Ross Sea since Last Glacial Maximum, Antarctica, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9982, https://doi.org/10.5194/egusphere-egu25-9982, 2025.
