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TitrePaleomagnetism of ca. 2.13-2.11 Ga Indin and ca. 1.885 Ga Ghost dyke swarms of the Slave craton: Implications for the Slave craton APW path and relative drift of Slave, Superior and Siberian cratons in the Paleoproterozoic
AuteurBuchan, K L; Mitchell, R N; Bleeker, W; Hamilton, M A; LeCheminant, A N
SourcePrecambrian Research vol. 275, 2016 p. 151-175, https://doi.org/10.1016/j.precamres.2016.01.012
Année2016
Séries alt.Secteur des sciences de la Terre, Contribution externe 20150252
ÉditeurElsevier
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1016/j.precamres.2016.01.012
Mediapapier; en ligne; numérique
Formatspdf
SNRC75A/03; 75A/04; 75A/05; 75A/06; 75A/11; 75A/12; 75A/13; 75A/14; 75B; 75C; 75D; 75E; 75F; 75G; 75H/03; 75H/04; 75H/05; 75H/06; 75H/11; 75H/12; 75H/13; 75H/14; 75I/03; 75I/04; 75I/05; 75I/06; 75I/11; 75I/12; 75I/13; 75I/14; 75J; 75K; 75L; 75M; 75N; 75O; 75P/03; 75P/04; 75P/05; 75P/06; 75P/11; 75P/12; 75P/13; 75P/14; 76A/03; 76A/04; 76A/05; 76A/06; 76A/11; 76A/12; 76A/13; 76A/14; 76B; 76C; 76D; 76E; 76F; 76G; 76H/03; 76H/04; 76H/05; 76H/06; 76H/11; 76H/12; 76H/13; 76H/14; 76I; 76J; 76K; 76L; 76M; 76N; 76O; 76P/03; 76P/04; 76P/05; 76P/06; 76P/11; 76P/12; 76P/13; 76P/14; 77A/02; 77A/03; 77A/04; 77A/05; 77A/06; 77A/07; 77A/10; 77A/11; 77A/12; 77A/13; 77A/14; 77A/15; 77B; 77C; 77D/02; 77D/03; 77D/04; 77D/05; 77D/06; 77D/07; 77D/10; 77D/11; 77D/12; 77D/13; 77D/14; 77D/15; 85A; 85B; 85C; 85F; 85G; 85H; 85I; 85J; 85K; 85N; 85O; 85P; 86A; 86B; 86C; 86F; 86G; 86H; 86I; 86J; 86K; 86N; 86O; 86P; 87A; 87B/01; 87B/02; 87B/07; 87B/08; 87B/09; 87B/10; 87B/15; 87B/16; 87C/01; 87C/02; 87C/07; 87C/08; 87C/09; 87C/10; 87C/15; 87C/16; 87D
Lat/Long OENS-118.0000 -105.0000 70.0000 60.0000
SujetsArchéen; craton; dérive du pôle; dérive du pôle; paléomagnétisme; filons rocheux; tectonique de plaques; datations au uranium-plomb; datation au uranium-plomb; interprétations paléomagnétiques; géophysique; géochronologie; tectonique; Protérozoïque
Illustrationslocation maps; geological sketch maps; tables; graphs
ProgrammeCoordination de IGC-4, Initiative géoscientifique ciblée (IGC-4)
Résumé(disponible en anglais seulement)
Of ~35 Archean cratons that have been identified around the globe, only one, the Superior craton of the Canadian Shield, has a reasonably well-defined apparent polar wander (APW) path for much of Paleoproterozoic time based on “key” (i.e., well-defined and precisely-dated) paleopoles. As a result it has not been possible to compare the drift of these cratons or reliably test continental reconstructions of the Archean cratons in the Paleoproterozoic based on paleomagnetism. In this study we report key paleopoles for the 2.13-2.11 Ga northwest- to north-northwest-trending Indin and 1.885 Ga northeast- to north-northeast-trending Ghost dyke swarms of the Yellowknife region of the Slave craton. U-Pb baddeleyite ages have been determined at paleomagnetic sampling sites and baked contact tests establish that the remanences are primary. Combined with paleopoles from other precisely-dated dyke swarms of the Slave craton, these data define a rudimentary APW path between ca. 2.23 and 1.885 Ga and permit a comparison of the drift of the Slave and Superior cratons over this interval. Both the Indin and Ghost poles are precisely matched in age with key poles on the Superior APW path. The Slave and Superior paths are not superimposed demonstrating that the two cratons were not in their present relative locations. They have different overall shapes indicating relative drift during at least a portion of the period. However, the earlier (2.23-2.21) portions of the tracks appear broadly similar and could permit the two cratons to be on a single tectonic plate at that time, although separated by a great distance. A comparison of the Ghost pole and a coeval key pole for Siberia permits a 1.88 Ga reconstruction with southern Siberia facing the northern Slave/Laurentia margin, broadly similar to reconstructions that have been proposed at least as late as 1.38 Ga, although the distance between the cratons is still poorly constrained.
Résumé(Résumé en langage clair et simple, non publié)
L'Initiative géoscientifique ciblée (IGC-4) est un programme géoscientifique fédéral de collaboration qui fournit à l'industrie les connaissances géoscientifiques et les techniques novatrices de prochaine génération dont elle a besoin pour mieux détecter les gîtes minéraux enfouis, réduisant ainsi certains risques liés à l'exploration. Pour dater avec précision les pôles paléomagnétiques, le plus facile est de travailler avec des essaims de dykes mafiques. Dans cette étude, la datation précise de paléopôles est réalisée à partir de deux essaims de dykes du Paléoprotérozoïque dans le craton des Esclaves en Amérique du Nord. On démontre que le craton des Esclaves et le craton du Supérieur de l'Amérique du Nord ont dérivé indépendamment sur des plaques tectoniques différentes au cours d'une partie importante de l'intervalle de 350 Ma compris entre 2230 et 1880 Ma. Une comparaison préliminaire des données du craton des Esclaves avec celles du craton de Sibérie est compatible avec l'hypothèse que ces deux cratons ont été relativement proches vers 1880 Ma.
GEOSCAN ID297012