A displaced and metamorphosed peralkaline granite related to the late Proterozoic Labrador and Gardar suites: the Doolough Granite of County Mayo, northwest Ireland

Abstract

The chemically and lithologically distinct Doolough Granite from the Annagh Division in northwest County Mayo, Ireland, includes part of the northwesternmost exposures of Precambrian basement in Europe. The Doolough Granite is similar to Precambrian granitic intrusions found in Labrador and southwest Greenland, although its age of emplacement at [Formula: see text] (U–Pb in zircon) is slightly younger than the Canadian intrusions. A reconstruction of the pre-Iapetus disposition of the eastern Laurentian margin suggests that the Doolough Granite was probably emplaced at a location sufficiently close to both southwest Greenland and Labrador for it to have formed part of the same magmatic province during a period of restricted crustal extension that preceded the Grenville event.