Conodont (U-Th)/He thermochronology: Initial results, potential, and problems

Daniel J. Peppe, Peter W. Reiners

Research output: Contribution to journalArticle

13 Scopus citations

Abstract

We performed He diffusion experiments and (U-Th)/He age determinations on conodonts from a variety of locations to explore the potential of conodont (U-Th)/He thermochronology to constrain thermal and exhumation histories of some sedimentary-rock dominated terrains. Based on two diffusion experiments and age results from some specimens, He diffusion in conodont elements appears to be similar to that in Durango apatite fragments of similar size, and closure temperatures are approximately 60-70 °C (for cooling rates of ∼ 10 °C/m.y.). (U-Th)/He ages of conodonts from some locations yield reproducible ages consistent with regional thermal history constraints and, in at least two cases, require a closure temperature lower than ∼ 80 °C. Other samples however, yield irreproducible ages, and in one case yield ages much younger than expected based on regional geologic considerations. These irreproducible samples show inverse correlations between parent nuclides and age consistent with late-stage open-system U-Th behavior.

Original languageEnglish (US)
Pages (from-to)569-580
Number of pages12
JournalEarth and Planetary Science Letters
Volume258
Issue number3-4
DOIs
StatePublished - Jun 30 2007

    Fingerprint

Keywords

  • (U-Th)/He
  • conodonts
  • geochronology
  • thermochronology

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

Cite this