Mid-Eocene renewal of magmatism in NW Scotland the Loch Roag Dyke, outer hebrides
Amonchquite dyke, in the vicinity of Loch Roag, Lewis, Outer Hebrides has an unusually enriched chemistry, and contains a unique assemblage of megacrysts and xenoliths from the lithosphere of the Hebridean craton. A Ar-40/Ar-39 plateau age of 45.2 +/- 0.2 Ma (2 sigma) of a phlogopite megacryst from...
Published in: | Journal of the Geological Society |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2012
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Subjects: | |
Online Access: | https://publishup.uni-potsdam.de/frontdoor/index/index/docId/36083 https://doi.org/10.1144/0016-76492011-117 |
Summary: | Amonchquite dyke, in the vicinity of Loch Roag, Lewis, Outer Hebrides has an unusually enriched chemistry, and contains a unique assemblage of megacrysts and xenoliths from the lithosphere of the Hebridean craton. A Ar-40/Ar-39 plateau age of 45.2 +/- 0.2 Ma (2 sigma) of a phlogopite megacryst from the dyke overlaps an earlier reported K-Ar age, and confirms that the British Palaeogene Igneous Province extended into the Eocene. Similar late low-volume melts were erupted in the Eocene and Oligocene in West and East Greenland, suggesting that such late-stage magmatic rejuvenescence is a widespread feature across the North Atlantic Igneous Province. |
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