|Titre||Seismic interpretation of Ellesmerian, Mesozoic, and Cenozoic structural trends in the subsurface of Banks Island, NWT in support of surface geological and petroleum system mapping objectives|
|Auteur||Atkinson, E A; King, H M; Piepjohn, K; Dewing, K E; McCarthy, W M|
|Source||CTG 2018, Saints-Martyrs-Canadiens, Quebec Appalachians: program, abstracts and field guide, 28-30 September 2018; par Tremblay, A; Corrigan, D; Perrot, M; 2018 p. 5|
|Liens||Online - En
ligne (complete volume - volume complet, pdf, 2.77 MB) |
|Séries alt.||Ressources naturelles Canada, Contribution externe 20180205|
|Éditeur||Canadian Tectonics Group|
|Réunion||CTG 2018: 2018 Canadian Tectonics Group Workshop; Saint-Martyrs-Canadiens, QC; CA; Septembre 28-30, 2018|
|Media||papier; en ligne; numérique|
|Province||Territoires du Nord-Ouest|
|SNRC||88B; 88C; 88D; 88F; 97G; 97H; 98A; 98B; 98C; 98D; 98E; 98F|
|Lat/Long OENS||-127.0000 -113.5000 75.0000 71.0000|
|Sujets||interprétations géophysiques; interpretations sismiques; géologie du substratum rocheux; caractéristiques structurales; failles; plis; tendances structurelles; ressources pétrolières; capacité de
production d'hydrocarbures; estimation des ressources; corrélation; interprétations tectoniques; Orogenèse Ellesmerienne; Ceinture de Parry Islands Fold ; géologie régional; géologie structurale; combustibles fossiles; géophysique; Nature et
environnement; Phanérozoïque; Cénozoïque; Tertiaire; Mésozoïque; Crétacé; Jurassique; Paléozoïque; Dévonien|
|Programme||Les géosciences pour les nouvelles sources d'énergie, La coordination du programme|
|Diffusé||2018 09 01|
|Résumé||(disponible en anglais seulement)|
Banks Island is located in the westernmost Canadian Arctic Islands. It is located between the Parry Islands Fold Belt to the NE and the Mackenzie Delta to the
SW. The regional Geological Survey of Canada maps for the area (Miall, 1979) suggested that the exposed Cretaceous and Cenozoic deposits are relatively undisturbed. A few broad low amplitude folds were the main structures noted, and almost no
faulting was mapped outside of limited Paleozoic outcrops. There was significant petroleum exploration in the 70's and early 80's, and 8 of the 11 wells were incorporated into the GSC regional mapping, but the petroleum industry seismic data and
interpretation remained confidential in that era. Generally in the public scientific literature, the subsurface structures, including the Banks Graben, were only broadly outlined from the wells and gravity data.
In 2016, new field work was
undertaken under the GSC's Geo-mapping for Energy and Minerals (GEM) program, in cooperation with the German BGR. In addition, there was a new mandate for regional petroleum resource assessment, as part of the Marine Conservation Targets* (MCT)
initiative. In preparation for these projects, the legacy petroleum industry data were assembled in one location. Seismic data were loaded into geophysical interpretation software, as images of the data that were required to be submitted to the
National Energy Board, and digital seismic data** donated from various petroleum companies. Raw field records were also donated and reprocessed to modern standards, with significant uplift in image quality. The assembled database allows new regional
mapping of the subsurface structure in support of both programs.
The first mapping effort focused on the Northern Banks Graben in advance of the 2016 field work. An extensive array of (apparent) normal faults forming the graben are well imaged,
and the faults were correlated with the aide of 3D visualization. Such visualization increased the confidence of fault correlation, despite the distance between seismic lines. A projected surface trace map was very successful in helping to locate
surface exposures of faults for further analysis. Field work observations showed more complex movement on these structures including significant strike slip motion, only hinted at on the regional seismic images (Piepjohn et al, 2018). Both field
observations and subsurface mapping (fault limited deposition and growth strata) suggest that these faults have a protracted history from the Jurassic to at least the Eocene. Ongoing regional mapping has extended deeper in the stratigraphic section,
and outlines significant constraints on Ellesmerian (Devonian) trends. Broad folding of significant amplitude is observed prior to a regional pre-Jurassic unconformity in NW Banks Island. The orientation of this folding is compatible with similar
aged structures in the Parry Islands Fold Belt to the NE, and may indicate the Ellesmerian structural front is a more simple arc - an interesting observation for the tectonic history. Much additional potential for insight from further reprocessing
and mapping remains.
Miall, A.D., 1979. Mesozoic and Tertiary geology of Banks Island, Arctic Canada - The history of an unstable craton margin; Geological Survery of Canada Memoir 387, 235p.
Piepjohn, K., Atkinson, E., Dewing,
K., Smith, R., and Galloway, J., 2018. Cenozoic structural evolution on northern Banks Island, NWT Canada; Arktos V.4, no.15, 19p.
* The Marine Conservation Targets (MCT) initiative provides targeted funding to Environment and Climate Change
Canada (represented by the Parks Canada Agency), Fisheries and Oceans Canada (DFO), and Natural Resources Canada (NRCan) as part of the Government of Canada's commitment to conserve 10% of Canada's marine and coastal waters within the 200 nautical
mile limit by 2020.
** The GSC thanks Suncor Energy and an anonymous petroleum company, for significant donations of digital seismic data, and permission to publish images of some of that data.