Multiple high-pressure metamorphic events and crustal telescoping in the NW Highlands of Scotland C.D. Storey T.S. Brewer R. Anczkiewicz R.R. Parrish M.F. Thirlwall 10.6084/m9.figshare.3454784.v1 https://geolsoc.figshare.com/articles/dataset/Multiple_high-pressure_metamorphic_events_and_crustal_telescoping_in_the_NW_Highlands_of_Scotland/3454784 <p>The Glenelg–Attadale Inlier is the largest basement inlier within the Caledonian orogen in NW Scotland. A Western Unit consists of trondhjemite–tonalite–granodiorite (TTG) gneisses and subordinate mafic intrusions with locally preserved mafic high-pressure granulite and eclogite assemblages. An Eastern Unit comprises TTG gneisses, Grenville-age (<em>c</em>. 1.1 Ga) eclogite and metasediments. U–Pb zircon ages from the Western Unit TTG gneisses are highly disturbed with Neoarchaean upper intercepts and Palaeo- to Mesoproterozoic lower intercepts, suggesting strong reworking at these times. U–Pb zircon, Sm–Nd and Lu–Hf garnet–clinopyroxene dates from the Western Unit high-pressure granulite and eclogite yield Neoarchaean (<em>c</em>. 2.6–2.8 Ga) and Palaeoproterozoic (<em>c</em>. 1.75 Ga) ages, respectively. These ages correspond to the ages of partial resetting of the TTG gneisses. The eclogite in the Western Unit may represent the high-pressure convergent margin to the lower-pressure Laxfordian events within the Lewisian Gneiss Complex, whereas the Mesoproterozoic eclogites in the Eastern Unit may represent a farther eastward Grenville-age margin. Further east, Ordovician high-pressure granulites within the Moine Supergroup may represent another, later, Grampian convergent margin. These high-pressure belts were developed sequentially towards the east and telescoped westwards from Palaeoproterozoic to Early Palaeozoic times. </p> 2016-06-21 12:21:01 TTG gneisses Eastern Unit granulite Ga Western Unit NW eclogite Grampian convergent margin Western Unit TTG gneisses Lewisian Gneiss Complex Geology