Título: | DEVELOPMENT OF A METHODOLOGY FOR CORALS AND SPELEOTHEMS DATING USING THE 230-TH/234-U METHOD, THROUGH CHROMATOGRAPHIC SEPARATION AND QUANTIFICATION BY ALPHA SPECTROMETRY AND FIA-ICP-MS | ||||||||||||||||||||||||||||||||||||||||
Autor: |
ROSANA PETINATTI DA CRUZ |
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Colaborador(es): |
JOSE MARCUS DE OLIVEIRA GODOY - Orientador |
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Catalogação: | 19/JUN/2006 | Língua(s): | PORTUGUESE - BRAZIL |
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Tipo: | TEXT | Subtipo: | THESIS | ||||||||||||||||||||||||||||||||||||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
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Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=8544&idi=1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=8544&idi=2 |
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DOI: | https://doi.org/10.17771/PUCRio.acad.8544 | ||||||||||||||||||||||||||||||||||||||||
Resumo: | |||||||||||||||||||||||||||||||||||||||||
This paper discusses the age determination of speleothems
and corals using
Uranium-series- imbalance method, more specifically the
daughter deficient
method - DD, particularly the 230Th/234U method. Different
methodologies were
tested using chromatographic extraction separation and
quantification by alpha
spectrometry and ICP-MS. Three different procedures were
tested: batch
separation using columns with Tri-N-Octylphosphine Oxide
(TOPO) in silica gel
and TRU column commercialized by Eichrom(R) composed of
octyl-N,N,-isobutyl
carbamoylphosphine oxide dissolved in tri-n-butyl
phosphate (TBP) and with
quantification by alpha spectrometry; batch separation
with the same systems, but
with quantification by ICP-MS; and flow injection with TRU
cartridges and
qualification by ICP-MS. The methodologies developed were
verified using
certified reference samples, IAEA-327 (soil) with 2%
imprecision rate for the
method using flow injection with TRU cartridges and
qualification by ICP-MS.
The speleothem samples analyzed were collected at Carste
de Lagoa Santa, in the
state of Minas Gerais, by Prof. Luis Piló`s (USP) group,
and their ages varied
from 15,2±2,2 kyears to >350 kyears. These numbers are
within the range found
in the literature for speleothem samples collected by the
same group in the same
region. The coral sample, collected at Bacia de Campos
(RJ), and from the
Lophelia pertusa species, was subdivided according to its
ramifications (primary,
secondary and tertiary), and the main ramification dated
9,4 ± 0,3 kyears.
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