Here we investigate the feasibility of using alpha-spectrometric 226Ra methodology to date low U freshwater carbonate deposits (<0.1 μg g-1) by analysing Holocene freshwater travertine deposits from Esanatoglia, Umbro-Marchean Apennines, Central Italy. Previously, such methods have been tested on hydrothermal deposits, which are characterised by high Ra and U. We calculate a 226Ra age estimate of 2.9 ± 0.4 ka (1σ) for Holocene travertine that is in reasonable agreement with archaeological evidence by assuming that the 226Ra initial activity of the Holocene travertine is comparable with that of present-day carbonate deposits in the same area. We also investigate the use of Ba to normalise 226Ra activities. Comparison of age estimates based on Ra methods with ages derived from alphaspectrometric 230Th/234U isochron techniques for the same co-eval sub-samples indicates that, where only alpha-spectrometric methods are available, the former are likely to be much more useful for Holocene travertine material, especially if there is a significant detrital component.

Soligo, M., Tuccimei, P. (2008). 226Ra chronology of Holocene travertine from Esanatoglia (Central Italy). QUATERNARY GEOCHRONOLOGY, 3, 89-98 [10.1016/j.quageo.2007.10.002].

226Ra chronology of Holocene travertine from Esanatoglia (Central Italy)

SOLIGO, Michele;TUCCIMEI, Paola
2008-01-01

Abstract

Here we investigate the feasibility of using alpha-spectrometric 226Ra methodology to date low U freshwater carbonate deposits (<0.1 μg g-1) by analysing Holocene freshwater travertine deposits from Esanatoglia, Umbro-Marchean Apennines, Central Italy. Previously, such methods have been tested on hydrothermal deposits, which are characterised by high Ra and U. We calculate a 226Ra age estimate of 2.9 ± 0.4 ka (1σ) for Holocene travertine that is in reasonable agreement with archaeological evidence by assuming that the 226Ra initial activity of the Holocene travertine is comparable with that of present-day carbonate deposits in the same area. We also investigate the use of Ba to normalise 226Ra activities. Comparison of age estimates based on Ra methods with ages derived from alphaspectrometric 230Th/234U isochron techniques for the same co-eval sub-samples indicates that, where only alpha-spectrometric methods are available, the former are likely to be much more useful for Holocene travertine material, especially if there is a significant detrital component.
Soligo, M., Tuccimei, P. (2008). 226Ra chronology of Holocene travertine from Esanatoglia (Central Italy). QUATERNARY GEOCHRONOLOGY, 3, 89-98 [10.1016/j.quageo.2007.10.002].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11590/139710
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 5
  • ???jsp.display-item.citation.isi??? 4
social impact