| Title | Structural evolution of the Thetford Mines Ophiolite Complex, Canada: implications for the southern Québec ophiolitic belt |
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| Author | Schroetter, J -M; Bédard, J H; Tremblay, A |
| Source | Tectonics vol. 24, no. 1, TC1001, 2005, 20 pages, https://doi.org/10.1029/2003TC001601  Open Access |
| Image |  |
| Year | 2005 |
| Alt Series | Earth Sciences Sector, Contribution Series 2005286 |
| Publisher | Wiley-Blackwell |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Quebec |
| NTS | 21E/04; 21E/05; 21E/06; 21E/10; 21E/11; 21E/12; 21E/13; 21E/14; 21E/15; 21L; 31H/01; 31H/02; 31H/03; 31H/06; 31H/07; 31H/08; 31H/09; 31H/10; 31H/11; 31H/14; 31H/15; 31H/16; 31I/01; 31I/02; 31I/08 |
| Area | Chaudière River; St. Lawrence River; Saint-François River; Coleraine; Asbestos; Saint-Élie-de-Brompton; Mont Adstock; Thetford Mines; Mont Ham; Mont Caribou; Nadeau Hill; Breeches Lake; Back Lake; Disraeli;
Lac Brompton; Mont Chauve; Monjoie Lake; Mont Orford; Eastman |
| Lat/Long WENS | -73.5000 -70.0000 47.0000 45.0000 |
| Subjects | structural geology; tectonics; igneous and metamorphic petrology; ophiolites; igneous rocks; volcanic rocks; metamorphic rocks; sedimentary rocks; structural features; faults; granites; sediments;
slates; limestones; sandstones; conglomerates; mudstones; siltstones; basalts; quartzites; phyllites; olistostromes; schists; faults, normal; obduction; ultramafic rocks; intrusions; dykes; faults, extension; sea floor spreading; subduction zones;
basins; metamorphic zones; continental margins; aureoles; emplacement; folds; faults, thrust; faults, reverse; tectonic history; oceanic lithosphere; anticlines; synclines; deformation; flysch; tuffs; plutonic rocks; facies; dunites; pyroxenites;
gabbros; diabases; harzburgites; mantle; amphibolites; lavas; breccias; turbidites; tectonites; foliation; fracturing; metasedimentary rocks; serpentinites; bedding; schistosity; cleavage; garnet; peridotites; chromitites; models; kinematic analysis;
magmatic arcs; lithology; geochemical analyses; Southern Quebec ophiolitic belt; Thetford Mines Ophiolite Complex; Asbestos Ophiolitic Complex; Mont Orford Ophiolitic Complex; Dunnage Zone; Magog Group; Ascot Complex; St-Daniel Melange; Humber Zone;
Sutton-Bennett Schists; Appalachian Orogen; Notre-Dame mountains anticlinorium; Sutton mountains anticlinorium; Brome Fault; Saint-Joseph Fault; Bennett Fault; La Guadeloupe Fault; Logan's Line; Taconian Orogen; Beauceville Formation; Saint-Victor
Formation; Rosaire Group; Caldwell Group; Bennett Schists; Becancour Anticline; Carineault Anticline; Acadian Orogeny; Coleraine breccias; Thetford Mine massif; Adstock-Ham massif; Reed-Bélanger Mine; Nadeau Mine; Normandie Mine; Beaver Mine;
American Chrome Mine; Jeffrey Mine; Lac Brompton Massif; Mont-Chauve Massif; Mont-Orford-Mont-Chagnon Massif; Sutton Schists; Mont-Adstock-Mont-Ham massif; Laurentian Margin; Phanerozoic; Paleozoic; Carboniferous; Devonian; Silurian; Ordovician;
Cambrian |
| Illustrations | geological sketch maps; location maps; schematic diagrams; sketches; photographs; cross-sections; models |
| Program | NSERC Natural Sciences and Engineering Research Council of
Canada |
| Program | Valorisation-Recherche Québec,
Diversification de l'exploration minérale au Québec |
| Released | 2005 01 11 |
| Abstract | The Thetford Mines Ophiolite Complex (TMOC) preserves a complete ophiolitic sequence, and occupies the hanging wall of a major SE dipping normal fault, the Saint-Joseph fault. Preobduction,
synobduction, and postobduction structures can be recognized in the TMOC. NS trending, preobduction, paleonormal faults are parallel to ultramafic minor intrusions, and to sheeted dykes, recording extension related to seafloor-spreading in a
pericontinental suprasubduction zone basin. WNW trending synobduction, synmetamorphic fabrics are found toward the base of the TMOC and in the underlying continental margin rocks, but are absent in the upper part of the TMOC and overlying sedimentary
rocks. These Ordovician (Taconian) structures record the development of a dynamothermal aureole immediately below the mantle/margin contact, and emplacement of the young ophiolite onto the continental margin. Postobduction structures include Late
Silurian/Early Devonian, SE verging backthrusts and back folds that inverted the TMOC; and Middle Devonian (Acadian) NW verging folds and reverse faults. The tectonic history established for the TMOC is consistent with that of the adjacent Laurentian
margin, and can be applied to the southern Québec ophiolitic belt as a whole. The structural synthesis of the ophiolitic belt, complemented with new observations and our compilation of stratigraphical, geochemical, geochronological, and petrological
data, suggests that the southern Québec ophiolites may represent the remnants of the obduction of a single large slab of suprasubduction oceanic lithosphere extending for over a 100 km of strike length. |
| GEOSCAN ID | 221068 |
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