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TitreBedrock geology, Strand Fiord-Expedition Fiord area, western Axel Heiberg Island, northern Nunavut (parts of NTS 59E, F, G, and H)
LicenceVeuillez noter que la Licence du gouvernement ouvert - Canada remplace toutes les licences antérieures.
AuteurHarrison, J C; Jackson, M P
SourceCommission géologique du Canada, Dossier public 5590, 2008, 14 pages; 1 CD-ROM, (Accès ouvert)
LiensMetadata - Métadonnées
ÉditeurRessources naturelles Canada
Documentdossier public
CartesCette publication contient 2 cartes
Info. cartegéologique, 1/100,000
Info. cartelocalisation, 1/200,000
Mediaen ligne; CD-ROM; numérique
Formatspdf (Adobe® Reader®); ppt (Microsoft PowerPoint); JPEG2000
SNRC59E/13; 59E/14; 59E/15; 59F/14; 59F/15; 59F/16; 59G/01; 59G/02; 59G/03; 59G/06; 59G/07; 59G/08; 59G/09; 59G/10; 59G/11; 59H/02; 59H/03; 59H/04; 59H/05; 59H/06; 59H/07; 59H/10; 59H/11; 59H/12
Lat/Long OENS-94.5000 -89.5000 79.9000 78.9167
Sujetsroches sédimentaires; grès; évaporites; diapirs; milieux tectoniques; antécédents tectoniques; tectonique de plaques; caractéristiques structurales; plis; analyses stratigraphiques; corrélations stratigraphiques; isopaques; analyses stratigraphiques; Paléocène; Eocene; roches mères; reservoirs; roches reservoirs; ressources; ressources pétrolières; Bassin de Sverdrup ; Formation d'Awingak ; Formation de Bastion Ridge ; Formation de Christopher ; Formation de Deer Bay ; Formation d'Expedition ; Formation d'Hassel ; Formation d'Heiberg ; Formation d'Iceberg Bay ; Membre d'Invincible Point ; Formation d'Isachsen ; Formation de Kanguk ; Membre de Macdougall Point ; Lits de Savik ; Formation de Strand Bay ; Formation d'Otto Fiord ; Formation de Blind Fiord ; Formation de Blaa Mountain ; Groupe d'Eureka Sound ; tectonique; géologie structurale; stratigraphie; combustibles fossiles; Mésozoïque; Crétacé; Trias; Paléozoïque; Carbonifère
Illustrationscross-sections; correlation charts; stratigraphic sections; photographs
Diffusé2008 08 21
Résumé(disponible en anglais seulement)
Axel Heiberg Island (Nunavut Territory) contains the thickest Mesozoic section in the Sverdrup Basin, and the ~370-km-long island is second only to Iran in the number and concentration of exposed evaporite diapirs. However, local geology and tectonic history have hardly been studied. The polar desert provides excellent exposure of 46 diapirs of Carboniferous evaporites and associated minibasins. Paleogene (Eurekan) sinusoidal and box-fold anticlines trend roughly north on a regular ~20-km wavelength, and probably detach on autochthonous Carboniferous Otto Fiord evaporites. In contrast, a 60-km-wide area, known as the wall-and-basin structure (WABS) province, has a characteristic wavelength of <10 km, irregular fold spacing, and bimodal fold trends. Crooked walls of diapiric anhydrite crop out in the cores of tight anticlines. Wider, open synclinal minibasins separate the diapir walls. We interpret the WABS province to detach on a shallow evaporite canopy. The only other known exposed evaporite canopy is in the Great Kavir of Iran.
The WABS evaporite canopy comprises an allochthonous coalescence of evaporite diapirs that spread during the Hauterivian (mid-Cretaceous, ~130 Ma), close to the onset of sea floor spreading in Canada Basin and plume-related flood basalt volcanism associated with Alpha Ridge. Since then, the canopy has yielded second-generation diapirs, now exhumed and exposed by modest late Paleocene-Eocene shortening (Eurekan Orogeny). Local strata record minibasin evolution and diapirism since at least the Late Triassic. Diapir-flanking angular unconformities, involving proven reservoir sandstones, are present at four stratigraphic levels between the Jurassic and Paleocene. Most significant and widespread is the mid-Cretaceous event marking the time of canopy emplacement and spreading. Outcrops record the later fate of the canopy, including its subaerial exposure, onlap of diapiric evaporite, and off-diapir debris flows. Extensional tectonics evidently had a significant influence in the region from mid-Early Cretaceous (~125 Ma) to the mid-Late Cretaceous (~90 Ma) as indicated by diabase dyke swarms emplaced in several directions, extrusive basalt, and sills in most Mesozoic strata but especially common in the vicinity of some diapirs. A record of hyperactive fluid circulation includes fossil tufa deposits, migrated hydrocarbons, and metal sulphide deposits in diapir aureoles. Saline springs, recently-formed subaerial debris flows and geomorphically unstable diapir relief indicate that the evaporite canopy on western Axel Heiberg Island remains a geologically dynamic feature of the central Sverdrup Basin.