Abstract
To evaluate the effect of alteration on the K/Ar ages of volcanic rocks, the relation between the apparent K/Ar age and the H 2O(+) content was examined. For obsidian, there is a clear indication that hydrated samples lost some of their radiogenic argon, while fresh obsidians show more reliable K/Ar ages. For dredged submarine basalts, a similar tendency is observed: rocks with higher H 2O(=) contents show K/Ar ages younger than the rocks with lower H 2O(=) contents. Similar phenomena are also observed for subaerial basalts and andesites, although the tendency is sometimes less clear than in the obsidians and the submarine basalts. From these results, it is suggested that H 2O(=) content of volcanic rocks might be used as a criterion to check the validity of K/Ar ages: incomplete retention of radiogenic argon may occur in volcanic rocks containing more than 1% H 2O(=).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
