Avalonian and Cadomian Geology of the North Atlantic

1 Introduction.- References.- 2 The Longmyndian Supergroup and related Precambrian sediments of England and Wales.- 2.1 Introduction.- 2.2 Longmyndian Supergroup, Welsh Borderland.- 2.2.1 Stratigraphy of the Longmyndian Supergroup.- 2.2.2 Structure of the Longmyndian Supergroup.- 2.2.3 Sedimentology of the Longmyndian Supergroup.- 2.3 Old Radnor Inlier, Welsh Borderland.- 2.4 Charnian Supergroup, Leicestershire.- 2.5 Llangynog Inlier, Dyfed.- 2.6 Other outcrops of Precambrian sediments in England and the Welsh Borderland.- 2.7 Depositional setting of the Precambrian sediments.- References.- 3 Pre-Arenig terranes of northwest Wales.- 3.1 Introduction and historical perspective.- 3.2 The Monian Supergroup.- 3.3 The Coedana Complex.- 3.4 The southeast Anglesey blueschists.- 3.5 The Sara Complex.- 3.6 Regional correlations.- 3.7 Overstep sequences and age constraints.- 3.8 Monian tectonics: an overview.- References.- 4 The Rosslare Complex: a displaced terrane in southeast Ireland.- 4.1 Introduction.- 4.2 The Rosslare Complex: constituents and geological history.- 4.2.1 Early tectono-thermal history.- 4.4.2 The second event (M2).- 4.2.3 The third event (M3).- 4.2.4 The fourth event (M4).- 4.3 Rocks marginal to the Rosslare Complex.- 4.3.1 Tomhaggard Zone.- 4.3.2 Silverspring Zone.- 4.3.3 Tagoat Group.- 4.3.4 The Ballycogly Group.- 4.3.5 Cullenstown Formation.- 4.3.6 Tuskar Group.- 4.4 Caledonian intrusions.- 4.4.1 Saltees Granite.- 4.4.2 Younger basic dykes.- 4.4.3 Carnsore Granite.- 4.5 Conclusions.- References.- 5 Cadomian terranes in the North Armorican Massif, France.- 5.1 Introduction.- 5.2 St. Brieuc terrane (SBT).- 5.2.1 Pre-Cadomian Icartian basement.- 5.2.2 The Penthièvre complex.- 5.2.3 Brioverian supracrustals.- 5.2.4 Cadomian magmatism.- 5.3 St. Malo terrane (SMT).- 5.4 Mancellian terrane (MT).- 5.5 Nature and timing of deformation.- 5.6 Post-Cadomian sedimentation.- 5.7 Regional correlations.- 5.7.1 Guernsey, Sark, Alderney and Cap de la Hague.- 5.7.2 Jersey.- 5.7.3 Lower Normandy.- 5.8 Geotectonic setting.- References.- 6 Precambrian of the Bohemian Massif, Central Europe.- 6.1 Introduction.- 6.2 The Bohemian Massif.- 6.3 The Moldanubian.- 6.4 The Brioverian.- 6.4.1 The Lower Brioverian.- 6.4.2 The Middle Brioverian.- 6.4.3 The Upper Brioverian.- 6.5 Unit boundaries.- 6.6 Cadomian deformation.- 6.7 Cadomian metamorphism and plutonism.- References.- 7 Precambrian terranes in the Iberian Variscan Foldbelt.- 7.1 Introduction.- 7.2 Precambrian sequences and history of northwest Iberia suspect terranes.- 7.3 Stratigraphy of Precambrian sequences in the Iberian terrane.- 7.3.1 Pre-orogenic sequences.- 7.3.2 Syn-orogenic sequences.- 7.4 Late Precambrian tectono-thermal evolution of the Iberian terrane: the Cadomian orogeny.- 7.4.1 Cadomian deformational events.- 7.4.2 Cadomian metamorphism.- 7.4.3 Cadomian igneous activity.- 7.4.4 The Cadomian orogeny in the Iberian terrane from a terrane perspective.- References.- 8 The West African orogens and Circum-Atlantic correlatives.- 8.1 Introduction.- 8.2 Mauritanide, Bassaride, and Rokelide orogens.- 8.2.1 Geologic setting.- 8.2.2 Tectono-thermal history.- 8.2.3 Geophysical controls on tectonic models.- 8.2.4 Geodynamic models.- 8.3 Southern Appalachian orogen.- 8.4 Pre-Cretaceous crystalline basement beneath the Atlantic and Gulf Coastal Plains of the southeastern United States.- 8.4.1 Suwannee terrane.- 8.4.2 Structure.- 8.4.3 Relationship to Appalachian elements.- 8.4.4 Wiggins Uplift.- 8.4.5 Southwestern Alabama Igneous Complex.- 8.4.6 Regional tectonic relations.- 8.5 Appalachian—West African correlations.- 8.6 Terrane accretion in the southern Appalachian orogen.- References.- 9 The Avalon Zone type area: southeastern Newfoundland Appalachians.- 9.1 Introduction.- 9.2 Characteristic lithology and age.- 9.3 Boundaries.- 9.4 Precambrian stratigraphy.- 9.4.1 Pre-635 Ma rocks.- 9.4.2 Late Precambrian (635 Ma–600 Ma) volcanic rocks.- 9.4.3 Late Precambrian (635 Ma–c. 570 Ma) marine sedimentary rocks.- 9.4.4 Latest Precambrian terrestrial sedimentary rocks.- 9.4.5 Latest Precambrian (c. 570 Ma) volcanic rocks.- 9.5 Late Precambrian plutonic rocks.- 9.6 Cambro-Ordovician stratigraphy.- 9.7 Mid-Palaeozoic stratigraphy.- 9.8 Palaeozoic plutonic rocks.- 9.9 Mesozoic magmatism.- 9.10 Tectono-thermal history.- 9.11 Synthesis.- 9.11.1 Deep crust.- 9.11.2 The Burin Group.- 9.11.3 Volcanic and plutonic rocks.- 9.11.4 Sedimentary rocks.- 9.11.5 Latest Precambrian rocks.- 9.11.6 The Eocambrian—Palaeozoic record.- 9.11.7 The Avalonian—Appalachian connection.- References.- 10 The Avalon Composite terrane of Nova Scotia.- 10.1 Introduction.- 10.2 Geological data.- 10.2.1 Mid/Late Proterozoic gneisses.- 10.2.2 Mid/Late Proterozoic platfonnal rocks.- 10.2.3 Late Proterozoic volcano-sedimentary rocks.- 10.2.4 Early Palaeozoic overstep sequences.- 10.3 Discussion.- References.- 11 The Avalon Zone of New Brunswick.- 11.1 Zone definition.- 11.2 Zone boundaries.- 11.3 Unit descriptions.- 11.3.1 Brookville Gneiss.- 11.3.2 Green Head Group.- 11.3.3 Martinon Formation.- 11.3.4 Early amphibolites?.- 11.3.5 Late Precambrian granitoid plutons (Golden Grove suite).- 11.3.6 Coldbrook Group.- 11.3.7 Kingston Dyke Complex(?).- 11.3.8 Late Precambrian (?) mylonite zones.- 11.3.9 ‘Eocambrian’ succession.- 11.3.10 Saint John Group.- 11.4 Regional correlations.- References.- 12 Palaeomagnetic and tectonic constraints on the development of Avalonian—Cadomian terranes in the North Atlantic region.- 12.1 Introduction.- 12.2 Palaeomagnetic constraints on a late Precambrian plate reconstruction.- 12.2.1 The main cratons.- 12.2.2 The intervening terranes.- 12.2.3 Comparison with previous reconstructions.- 12.3 Tectonic synthesis.- References.