Abstract:

Beaches are preserved above sea level along ice-free portions of the Antarctic coastline due to post-glacial rebound associated with glacial isostatic adjustment since the Last Glacial Maximum. The ages and elevations of these beaches provide relative sea-level constraints for glacial isostatic adjustment models and ice-sheet histories.  Due to harsh field conditions and difficulty dating Antarctic materials, a lack of geochronological constraints on raised beaches limit our understanding of relative sea-level around Antarctica. This talk focuses on the use of dated beaches to reconstruct relative sea level and better understand Antarctic coastal evolution throughout the Holocene. A relative sea-level history of Marguerite Bay, Antarctic Peninsula derived from optically stimulated luminescence-dated beach cobble surfaces further constrains post-glacial rebound since the Last Glacial Maximum around Antarctica. The temporal distribution of circum-Antarctic raised beaches throughout the Holocene is utilized to determine the relationship between wave-energy, sea ice, and coastal evolution. The findings of these studies focused on Antarctic raised beaches have implications for understanding sea-level, glacial isostatic adjustment, ice-sheet histories, and climate since the Last Glacial Maximum.