Preprints
https://doi.org/10.5194/gchron-2020-37
https://doi.org/10.5194/gchron-2020-37

  06 Jan 2021

06 Jan 2021

Review status: this preprint is currently under review for the journal GChron.

A simplified isotope dilution approach for the U-Pb dating of speleogenic and other low-232Th carbonates by multi-collector ICP-MS

Andrew J. Mason1, Anton Vaks1,a, Sebastian F. M. Breitenbach2, John N. Hooker1,b, and Gideon M. Henderson1 Andrew J. Mason et al.
  • 1Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
  • 2Department of Geography and Environmental Sciences, Northumbria University, Ellison Place, Newcastle upon Tyne, NE1 8ST, UK
  • apresent address: Geological Survey of Israel, 32 Yeshayahu Leibowitz Street, 9692100 Jerusalem, Israel
  • bpresent address: Department of Geosciences, Penn State University, 503 Deike Building, University Park, PA 16802, USA

Abstract. We describe a new method for the measurement of U/Pb ratios by isotope dilution multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for the dating of geologically young clean carbonates, particularly speleothems. The method is intended for materials containing little or no initial 232Th. We illustrate and validate the method with four examples ranging from 0.57 Ma to 20 Ma old. The new method is capable of applying the 235U-207 and 238U-234U-206Pb chronometers, common Pb and quantifiable residual 234U/238U disequilibrium permitting. These provide an alternative to the more widely used 238U-206Pb chronometer, which can be highly inaccurate for samples a few million years old, owing to uncertainties in the excess initial 234U (hence, excess radiogenic 206Pb) commonly observed in speleothems.

Andrew J. Mason et al.

Status: open (extended)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on gchron-2020-37', Robert Cliff, 18 Mar 2021 reply
    • AC1: 'Reply on RC1', Andrew Mason, 25 Mar 2021 reply

Andrew J. Mason et al.

Andrew J. Mason et al.

Viewed

Total article views: 338 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
254 76 8 338 4 3
  • HTML: 254
  • PDF: 76
  • XML: 8
  • Total: 338
  • BibTeX: 4
  • EndNote: 3
Views and downloads (calculated since 06 Jan 2021)
Cumulative views and downloads (calculated since 06 Jan 2021)

Viewed (geographical distribution)

Total article views: 272 (including HTML, PDF, and XML) Thereof 268 with geography defined and 4 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 11 Apr 2021
Download
Short summary
A novel technique for the uranium-lead dating of geologically young carbonates is described and tested. The technique expands our ability to date geological events such as fault movements and past climate records.