THE AGE OF ALKALINE ROCKS FROM WEST FINNMARK, NORTHERN NORWAY, AND THEIR BEARING ON THE DATING OF THE CALEDONIAN OROGENY

The results of 27 new potassium-argon age determinations on alkaline rocks from Si:iroy, Seiland, and Stjemi:iy are presented. These fall in to two major groups, i.e. 480-491 m.y. and 384-420 m.y., which are thought to correspond with two major phases of the Caledonian orogeny.

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