Limits on the tectonic significance of rapid cooling events in extensional settings: insights from the Bitterroot metamorphic core complex, Idaho-Montana

M. A. House, K. V. Hodges

Research output: Contribution to journalArticle

31 Scopus citations

Abstract

Rapid cooling events deduced from thermochronologic data are often interpreted to be coincident with the age of extensional denudation in metamorphic core complexes. 40 Ar/ 39 Ar data for mylonitic and nonmylonitic footwall rocks from the Bitterroot core complex, Idaho-Montana, US, Challenge this view. Newly obtained hornblende 40 Ar/ 39 Ar cooling ages for samples collected from the mylonite zone suggest a time lag of ~1-3 m.y. between the age of unroofing and the time of thermal reequilibration. These data suggest caution in the use of 40 Ar/ 39 Ar data from the footwalls of metamorphic core complexes to suggest the precise age of tectonic denudation. -from Authors

Original languageEnglish (US)
Pages (from-to)1007-1010
Number of pages4
JournalGeology
Volume22
Issue number11
DOIs
StatePublished - Jan 1 1994
Externally publishedYes

ASJC Scopus subject areas

  • Geology

Fingerprint Dive into the research topics of 'Limits on the tectonic significance of rapid cooling events in extensional settings: insights from the Bitterroot metamorphic core complex, Idaho-Montana'. Together they form a unique fingerprint.

  • Cite this