| Title | The multi-phase Keele Arch, central Mackenzie Corridor, Northwest Territories |
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| Author | MacLean, B C; Fallas, K M ; Hadlari, T |
| Source | Bulletin of Canadian Petroleum Geology vol. 62, no. 2, 2014 p. 68-104, https://doi.org/10.2113/gscpgbull.62.2.68 |
| Image |  |
| Year | 2014 |
| Alt Series | Earth Sciences Sector, Contribution Series 20130275 |
| Publisher | GeoScienceWorld |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 96C; 96D; 96E; 96F; 96K; 96L; 96M; 96N |
| Area | Mackenzie River; Great Bear Lake; Colville Hills; Lac des Bois |
| Lat/Long WENS | -128.0000 -123.0000 68.0000 63.0000 |
| Subjects | fossil fuels; tectonics; stratigraphy; crustal uplift; tectonic history; tectonic interpretations; tectonic history; subsidence; stratigraphic analyses; Keele Arch; Mackenzie Corridor; Brackett Basin;
Mount Cap Formation; Saline River Formation; Mount Kindle Formation; Franklin Mountain Formation; Paleozoic; Ordovician; Cambrian; Silurian; Mesozoic; Cretaceous; Devonian |
| Illustrations | location maps; stratigraphic columns; cross-sections |
| Program | GEM:
Geo-mapping for Energy and Minerals Mackenzie Delta and Corridor |
| Released | 2014 07 07 |
| Abstract | Keele Arch is a zone of anomalous structural, erosional, and depositional features along a corridor east of the Colville Hills and the northern Franklin Mountains, Northwest Territories, a region with
significant economic potential. First described in 1975, it has since been found to have had a long history of uplift-to-sag reversals. This report presents a series of maps and sections, based largely on flattened reflection seismic lines that
illustrate key stages of the arch's development through time and space. In doing so it lays the foundation for future assessments of the arch's influence on the surrounding stratigraphy. Preceded by a late Proterozoic syncline, it evolved through
five major stages: 1) subsidence into a chain of Cambrian to mid-Ordovician grabens; 2) upliftof its central and southern zones to form a Late Silurian (pre-Devonian) arch;3) renewed uplift into a pre-Cretaceous arch between the region east the
Colville Hills and the Mackenzie River valley near Johnson River; 4) mid-Cretaceous reactivation of the pre-Cretaceous and southern pre-Devonian arches; and5) subsidence of its central zone into Brackett Basin during the late-Campanian to Paleocene
and inversion of the Cambrian McConnell Graben into the McConnell Range during late-Campanian to Paleocene time. The feature can be divided into four parts: 1) A northern segment between the Northern Franklin Mountains and the region east of the
Colville Hills; 2) The north half of its central zone, where Cambro-Ordovician strata are exposed east of the northern Franklin Mountains; 3) The southern portion of the central zone between Brackett Lake and Keele River, where Tertiary rocks lie at
the surface. This is the best documented and most tectonically active segment; and 4) a poorly understood segment under Mackenzie Valley, south of Keele River. |
| Summary | (Plain Language Summary, not published)
Keele anomaly is today an arch extending from north of Lac des Bois to near Johnson R in the NWT but has undergone both subsidence and uplift.
Paleo-geology maps and sections show six development phases: 1) uplift - very early Cambrian bulge. 2) subsidence - graben chain in Cambrian to mid-Ordovician time. 3) uplift - Keele Tectonic Zone (KTZ) and an area to its south in the Late Silurian.
4) renewed uplift - pre-Cretaceous arch. 5) reactivation of the pre-Cret, and part of the pre-Dev, arch during the mid-Cret. 6) subsidence - Brackett Basin in late-Campanian to Paleocene and Eocene inversion of McConnell Graben into McConnell Range.
The anomaly has four parts: 1) Northern Franklin Mtns to Lac des Bois. 2) The north half of KTZ (northern Franklin Mtns). 3) The south half of KTZ (Brackett L. to Keele R). 4) Under Mackenzie Valley, south of Keele R. Axes in two sets: eastern set
of Camb. to mid-Ord. sags and latest Sil. to Eocene uplifts; western set of Camb. to mid-Cret. arches. |
| GEOSCAN ID | 293141 |
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