A lower Devonian point in the geological timescale.
- 1 January 1977
- journal article
- research article
- Published by Geochemical Society of Japan in GEOCHEMICAL JOURNAL
- Vol. 11 (3) , 147-153
- https://doi.org/10.2343/geochemj.11.147
Abstract
The Gocup Granite, in southeastern New South Wales, intrudes low-grade metasediments tentatively assigned to the Ludlovian on fragmentary conodont evidence, and is overlain by a unit rich in volcanic material but containing a good brachiopod fauna of lower to middle Siegenian age. The K-Ar age of 4 muscovite samples is 409 .+-. 3 m.y. [million years]; a Rb-Sr whole-rock isochron on 5 samples yields a Model 1 age 402 .+-. 3 m.y., initial 87Sr/86Sr 0.7090 .+-. 0.0013. Preliminary data by X-ray fluorescence and unspiked strontium mass spectrometry illustrate the effects of some sources of experimental error.This publication has 4 references indexed in Scilit:
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