Sediment geochemistry in coastal maritime Antarctica (Admiraty Bay, King George Island): Evidence from rare earths and other elements
Carregando...
Data
Data de publicação
Autores IPEN
Orientador
Título da Revista
ISSN da Revista
Título do Volume
É parte de
É parte de
É parte de
Marine Chemistry
Exportar
Resumo
We report the concentrations of 22 elements in short coastal sediment cores of Admiralty Bay (King George Island, Antarctica)
determined by Neutron Activation Analysis. We focus the discussion on rare earth elements (REE) because their fractionation
patterns in sediments relative to local sources may offer insights about weathering, transportation, deposition, and diagenetic
processes. We found strong correlations between REE and Th, indicating detrital origin. Despite strong Eh gradients, the Thnormalized redox-sensitive elements (e.g., Eu, Ce, Fe, As, and others) showed little variability within the sedimentary environment.
The exceptions were U (depleted in the upper few centimeters) and Br (enriched in the upper few centimeters). While U appears to
be removed from seawater via uptake across the boundary of reducing sediments, the mechanisms driving Br accumulation are
unclear, but perhaps related to increasing diatom production driven by regional warming. A comparison with published
concentrations from rocks representing the regional eroding units showed that the characteristics of source rock could be
recognized in the REE fractionation patterns in our sediments. These results imply no significant alteration during weathering and
sediment transport in the coastal region of Admiralty Bay and the prevalence of strong periglacial erosion in ice-free areas of
MARITIME Antarctica in spite of the relatively mild regional environmental setting (e.g., high moisture and high temperatures).
Como referenciar
SANTOS, ISAAC R.; FAVARO, DEBORAH I.T.; SCHAEFER, CARLOS E.G.R.; SILVA FILHO, EMMANOEL V. Sediment geochemistry in coastal maritime Antarctica (Admiraty Bay, King George Island): Evidence from rare earths and other elements. Marine Chemistry, v. 107, p. 464-474, 2007. DOI: 10.1016/j.marchem.2007.09.006. Disponível em: http://repositorio.ipen.br/handle/123456789/5159. Acesso em: 30 Dec 2025.
Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.