Beryllium isotope signatures of ice shelves and sub-ice shelf circulation
Be isotopes are a useful tracer of sediment source and transport pathways but have not been widely tested in glacio-marine environments. We measured Be isotopes in a range of depositional environments from open marine, sub-ice shelf and subglacial settings throughout Prydz Bay, one of Antarctica...
| Published in: | Earth and Planetary Science Letters |
|---|---|
| Main Authors: | , , , , , , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
2019
|
| Subjects: | |
| Online Access: | https://researchprofiles.canberra.edu.au/en/publications/e9cae090-0e14-4169-9057-b61b7959d3c1 https://doi.org/10.1016/j.epsl.2018.10.004 http://www.scopus.com/inward/record.url?scp=85055582816&partnerID=8YFLogxK http://www.mendeley.com/research/beryllium-isotope-signatures-ice-shelves-subice-shelf-circulation |
| Summary: | Be isotopes are a useful tracer of sediment source and transport pathways but have not been widely tested in glacio-marine environments. We measured Be isotopes in a range of depositional environments from open marine, sub-ice shelf and subglacial settings throughout Prydz Bay, one of Antarctica's largest ice drainage systems. We find that strong sub-ice shelf and bottom current circulations can advect 10 Be-rich open marine sediments into an ice shelf cavity, and 10 Be-poor terrestrial sediments onto the continental shelf at the ice shelf outflow, meaning that 10 Be concentrations reflect sub-ice shelf circulation patterns rather than depositional environment. However, HCl-extractable 10 Be/ 9 Be ratios can provide a more robust discrimination of sediment deposited in open marine and sub-ice shelf settings. Thus, Be isotopes are a useful tracer of both environmental setting and sub-ice shelf circulation strength in both modern and paleo-ice sheet margins. |
|---|