RT Journal Article
T1 Paleomagnetic techniques can date speleothems with high concentrations of detrital material
A1 Sánchez-Moreno, Elisa M.
A1 Font, Eric
A1 Pavón Carrasco, Francisco Javier
A1 Dimuccio, Luca A.
A1 Hillaire-Marcel, Claude
A1 Ghaleb, Bassam
A1 Cunha, Lúcio
AB The U-series dating of young and 'dirty' speleothems is challenging due to difficulties in assessing the isotopic composition of detrital contaminants and the low-abundance of Th-230 generated in situ. Here we propose a new dating approach based on the comparison of a speleothem's paleomagnetic directions to reference curves from global paleomagnetic reconstructions. This approach is demonstrated on a stalagmite collected from the Soprador do Carvalho cave in the Central Region of Portugal. A radioisotopic age model, built using four U-series ages and three C-14, suggests relatively steady carbonate precipitation from similar to 5760 BCE until similar to 1920 CE. Forty-five 6 mm-thick subsamples were analyzed using alternating field and thermal demagnetization protocols, providing well-defined, primary magnetic directions. An age model of the stalagmite was obtained by fitting its paleomagnetic record with the reference paleosecular variation curves obtained by previous paleo-reconstruction models, applying statistical bootstrapping analysis to define their best fit. The resulting age models fit closely with the radioisotopic age model but provide a significantly higher time resolution. We reach the same conclusion when applying this approach to another stalagmite from the Algarve region of Portugal. Our approach thus appears a promising alternative to date young speleothems with high detrital contents.
PB Nature
SN 2045-2322
YR 2022
FD 2022-10-26
LK https://hdl.handle.net/20.500.14352/116840
UL https://hdl.handle.net/20.500.14352/116840
LA eng
NO Sánchez-Moreno, E.M., Font, E., Pavón-Carrasco, F.J. et al. Paleomagnetic techniques can date speleothems with high concentrations of detrital material. Sci Rep 12, 17936 (2022). https://doi.org/10.1038/s41598-022-21761-9
NO Portuguese Fundação para a Ciência e a Tecnologia
NO Ministerio de Ciencia, Innovación y Universidades (España)
NO Agencia Estatal de Investigación (España)
DS Docta Complutense
RD 17 abr 2025