Laxfordian Orogeny
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The Laxfordian orogeny was an orogenic (mountain building) event between 1.9 and 1 billion years ago. It primarily affected the North Atlantic Craton, in particular a section that cleaved off during the
Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
as the Scottish Shield Fragment, part of the
Lewisian complex The Lewisian complex or Lewisian gneiss is a suite of Precambrian metamorphic rocks that outcrop in the northwestern part of Scotland, forming part of the Hebridean Terrane and the North Atlantic Craton. These rocks are of Archaean and Paleoprote ...
within the
Hebridean Terrane The Hebridean Terrane is one of the terranes that form part of the Caledonian orogenic belt in northwest Scotland. Its boundary with the neighbouring Northern Highland Terrane is formed by the Moine Thrust Belt. The basement is formed by Archa ...
. The event produced deformation and high-grade metamorphism, migmatite formation and the emplacement
granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...
and
pegmatite A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic com ...
in the Loch Maree Group basement rocks between 1.9 and 1.8 billion years ago. From 1.6 to 1.4 billion years ago, brittle folds formed followed by crush belts in the final phase of the orogeny. Laxfordian orogenic belts have many similarities to the Nagssugtoqidian mobile belt in Greenland. The Laxfordian orogeny was followed by the Grenville orogeny.{{cite book , year=1977, title= Precambrian of the Northern Hemisphere, url=https://archive.org/details/precambriannorth00salo, url-access=limited, publisher=Elsevier,
141
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References

Proterozoic orogenies Geology of Scotland