Title | Identification of regional structural corridors in the Montney play using trend surface analysis combined with geophysical imaging, British Columbia and Alberta |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Wozniakowska, P; Eaton, D W; Deblonde, C; Mort, A; Ardakani, O H |
Source | Geological Survey of Canada, Open File 8814, 2021, 62 pages, https://doi.org/10.4095/328850 Open Access |
Links | Erratum
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Image |  |
Year | 2021 |
Publisher | Natural Resources Canada |
Document | open file |
Lang. | English |
Media | digital; on-line |
File format | readme
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File format | pdf; rtf; dbf (ESRI® ArcExplorer(TM)/ ArcReader(TM)); shp (ESRI® ArcExplorer(TM)/ ArcReader(TM)); docx (Microsoft® Word®) |
Province | Alberta; British Columbia |
NTS | 82; 83A; 83B; 83C; 83D; 83E; 83F; 83G; 83H; 83J; 83K; 83L; 83M; 83N; 84C; 84D; 84E; 84L; 93A; 93H; 93I; 93J; 93O; 93P; 94A; 94B; 94C; 94F; 94G; 94H; 94I; 94J; 94K; 94N; 94O; 94P |
Area | Fort St. John; Peace River; Dawson Creek; Grande Prairie; Fox Creek; Fort Nelson; Rocky Mountain Foothills |
Lat/Long WENS | -125.0000 -113.5000 60.0000 52.0000 |
Subjects | fossil fuels; structural geology; geophysics; tectonics; Science and Technology; Nature and Environment; Health and Safety; petroleum resources; hydrocarbons; sedimentary basins; structural
interpretations; structural controls; structural trends; trend surface analyses; modelling, structural; tectonic evolution; bedrock geology; structural features; grabens; faults; folds; geophysical interpretations; seismic interpretations; seismic
profiles; gravity interpretations; magnetic interpretations; well logging; seismic risk; seismicity; Montney Formation; Western Canada Sedimentary Basin; Dawson Creek Graben Complex; Rocky Mountain Thrust and Fold Belt; Wabamun Group; Montney Play;
Canadian Cordillera; Duvernay Play; Gordondale Structural Corridor; Rycroft Structural Corridor; Dunvegan Structural Corridor; Tangent Structural Corridor; Bovie Lake Structural Corridor; Hay River Structural Corridor; Methodology; Quality control;
Geographic data; Geographic information systems; Phanerozoic; Mesozoic; Cretaceous; Jurassic; Triassic; Paleozoic; Permian; Carboniferous; Devonian |
Illustrations | location maps; geoscientific sketch maps; flow diagrams; seismic profiles; schematic representations; tables; plots; schematic cross-sections; stratigraphic charts |
Program | Energy Geoscience Clean Energy Resources - Decreasing Environmental Risk |
Released | 2021 12 21; 2022 01 07 |
Abstract | The Western Canada Sedimentary Basin (WCSB) is a mature oil and gas basin with an extraordinary endowment of publicly accessible data. It contains structural elements of varying age, expressed as
folding, faulting, and fracturing, which provide a record of tectonic activity during basin evolution. Knowledge of the structural architecture of the basin is crucial to understand its tectonic evolution; it also provides essential input for a range
of geoscientific studies, including hydrogeology, geomechanics, and seismic risk analysis. This study focuses on an area defined by the subsurface extent of the Triassic Montney Formation, a region of the WCSB straddling the border between Alberta
and British Columbia, and covering an area of approximately 130,000 km2. In terms of regional structural elements, this area is roughly bisected by the east-west trending Dawson Creek Graben Complex (DCGC), which initially formed in the Late
Carboniferous, and is bordered to the southwest by the Late Cretaceous - Paleocene Rocky Mountain thrust and fold belt (TFB). The structural geology of this region has been extensively studied, but structural elements compiled from previous studies
exhibit inconsistencies arising from distinct subregions of investigation in previous studies, differences in the interpreted locations of faults, and inconsistent terminology. Moreover, in cases where faults are mapped based on unpublished
proprietary data, many existing interpretations suffer from a lack of reproducibility. In this study, publicly accessible data - formation tops derived from well logs, LITHOPROBE seismic profiles and regional potential-field grids, are used to
delineate regional structural elements. Where seismic profiles cross key structural features, these features are generally expressed as multi-stranded or en echelon faults and structurally-linked folds, rather than discrete faults. Furthermore, even
in areas of relatively tight well control, individual fault structures cannot be discerned in a robust manner, because the spatial sampling is insufficient to resolve fault strands. We have therefore adopted a structural-corridor approach, where
structural corridors are defined as laterally continuous trends, identified using geological trend surface analysis supported by geophysical data, that contain co-genetic faults and folds. Such structural trends have been documented in laboratory
models of basement-involved faults and some types of structural corridors have been described as flower structures. The distinction between discrete faults and structural corridors is particularly important for induced seismicity risk analysis, as
the hazard posed by a single large structure differs from the hazard presented by a corridor of smaller pre-existing faults. We have implemented a workflow that uses trend surface analysis based on formation tops, with extensive quality control,
combined with validation using available geophysical data. Seven formations are considered, from the Late Cretaceous Basal Fish Scale Zone (BFSZ) to the Wabamun Group. This approach helped to resolve the problem of limited spatial extent of available
seismic data and provided a broader spatial coverage, enabling the investigation of structural trends throughout the entirety of the Montney play. In total, we identified 34 major structural corridors and number of smaller-scale structures, for which
a GIS shapefile is included as a digital supplement to facilitate use of these features in other studies. Our study also outlines two buried regional foreland lobes of the Rocky Mountain TFB, both north and south of the DCGC. |
Summary | (Plain Language Summary, not published) This study defines a structural corridor as a laterally continuous spatial trend defined by a set of co-genetic structural features (faults and folds)
inferred using geological and/or geophysical data. This approach simplifies the interpretive process of association of structures observed using different datasets; for example, trend surface residuals for specific formations obtained using well
control, provide broad spatial coverage that can be validated and refined where seismic data transect a structural corridor. |
GEOSCAN ID | 328850 |
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