GEOSCAN, résultats de la recherche


TitreCounterclockwise rotation of the Arctic Alaska plate: best available model or untenable hypothesis for the opening of the Amerasia Basin
AuteurEmbry, A F
SourcePolarforschung vol. 68, 2000 p. 247-255
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 1999223
Documentpublication en série
ProvinceTerritoires du Nord-Ouest; Yukon
SNRC107C; 107D/03; 107D/04; 107D/05; 107D/06; 107D/11; 107D/12; 107D/13; 107D/14; 107E/03; 107E/04; 107E/05; 107E/06; 107E/11; 107E/12; 107E/13; 107E/14; 107F; 107G; 107H/03; 107H/04; 107H/05; 107H/06; 107H/11; 107H/12; 107H/13; 107H/14; 117D; 117E; 117H
Lat/Long OENS-140.0000 -130.0000 72.0000 69.0000
Sujetsbassins; géologie de l'arctique; climat arctique; pôles paléomagnétiques; paléomagnétisme; interprétations paléomagnétiques; levés aéromagnétiques; océanographie; levés océanographiques; paléogéographie; dérive des continents; géophysique; géologie marine; paléontologie; tectonique; géologie structurale
Illustrationslocation maps; geological sketch maps
Résumé(Sommaire disponible en anglais seulement)
For the past thirty years the most widely aeeepted model for the opening of Amerasia Basin of the Aretie Oeean has been that the basin openecl by eountereloekwise rotation of northern Alaska and acljaeent Russia (Aretie Alaska plate) away frorn the Canadian Aretie Arehipelago about a pole in the Maekenzie Delta region. Reeently LANE (1997) has ealled this modcl into question. Thus it is worth reviewing the main data and arguments for and against the model to determine if indeed it is untenable as claimed by Lane, 01' is still the best available model. The main evidenee in favour of the modcl includes the alignment of diverse geologieal lineaments ancl the eoineiclenee of Alaskan, Valanginian paleomagnetie poles with the eratonie one following plate restoration employing the rotation model. The odds of such restored matches oeeurring by chance are astronornic and thus sueh data provide very eonvineing evidenee for the rotation hypothesis. Reeent gravity and acromagnetic data have allowed the interpretation of a former spreading centrc with flanking anornalies. The orienration of these features is compatiblc with the rotation hypothesis, thus adding further support to the model. A review of the various points raised by LANE (1997) against the rotation model reveals that sorne arguments are bascd on insuffieient and inconclusive data, others are unsupported interpretations and still others are based on a selective marshalling of data. Overall it is assessed that none of Lanc's points argue convineingly against the rotation model anel that such a model is elearly the best available one for the opening of the Amerasia Basin.