Affordable Access

Publisher Website

Apparent argon diffusive loss40Ar/39Ar age spectra in amphiboles

Authors
Journal
Earth and Planetary Science Letters
0012-821X
Publisher
Elsevier
Publication Date
Volume
134
Identifiers
DOI: 10.1016/0012-821x(95)00113-q
Disciplines
  • Chemistry

Abstract

Abstract Detailed investigations have been made of two amphibole samples where 40Ar/ 39Ar age spectra have been interpreted to show argon diffusive loss. Both samples display complex compositional zoning that reflects partial major and minor element chemical re-equilibration during later thermal events that is associated with the loss of radiogenic 40Ar. The apparent diffusive loss age spectra in these samples are an artefact of this chemical re-equilibration process. One sample additionally shows the effect of potassium gain and contamination with a potassium-rich phase (biotite). The resulting ages in this sample are geologically meaningless and the apparent fit to a theoretical diffusive loss curve is coincidental. This study shows that volume diffusive loss of argon appears to operate at slower rates than argon loss by chemical re-equilibration in amphiboles.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments

More articles like this

Theargon-40 argon-39method for potassium-argon age...

on Geochimica et Cosmochimica Act... Jan 01, 1968

Argon in Apollo 15 green glass spherules (15426):4...

on Earth and Planetary Science Le... Jan 01, 1973

The interpretation of40Ar/39Ar apparent age spectr...

on Journal of Structural Geology Jan 01, 2004
More articles like this..