• journal_title：Journal of the Geological Society
• Contributor：C.D. Storey ; T.S. Brewer ; R. Anczkiewicz ; R.R. Parrish ; M.F. Thirlwall
• Publisher：Geological Society of London
• Date：2010-
• Format：text/html
• Language：en
• Identifier：10.1144/0016-76492009-024
• journal_abbrev：Journal of the Geological Society
• issn：0016-7649
• volume：167
• issue：3
• firstpage：455
• section：Research Article

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 (m>cm>. 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 (m>cm>. 2.6–2.8 Ga) and Palaeoproterozoic (m>cm>. 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.