Rubidium-strontium age determinations on micas from a geologically controlled, composite batholith

I. S. Williams, W. Compston, B. W. Chappell, T. Shirahase, T. Shirahase

    Research output: Contribution to journalArticle

    58 Citations (Scopus)


    Thirty biotite and two muscovite ages are reported from thirteen plutons in the Berridale Batholith, a thoroughly mapped composite batholith in southeastern Australia. Middle Ordovician country rocks place an older limit on the age of the batholith. The mica ages of samples from any one pluton agree within experimental error except in a few cases where later plutons caused metamorphic resetting. Significant age differences have been found between plutons. The mica ages are consistent with the mapped intrusive sequence and range between 420 m.y. And 429 m.y., which indicates cooling of the intrusives to the biotite blocking temperature of about 300°C during the Late Silurian and Early Devonian. The agreement between the muscovite and biotite ages and also one age from a total rock with high Rb/Sr suggests that this cooling interval was short. Copyright.

    Original languageEnglish
    Pages (from-to)497-505
    Number of pages9
    JournalJournal of the Geological Society of Australia
    Issue number4
    Publication statusPublished - 1 Jan 1975

    Fingerprint Dive into the research topics of 'Rubidium-strontium age determinations on micas from a geologically controlled, composite batholith'. Together they form a unique fingerprint.

  • Cite this