Northern Mackenzie Mountains Research Articles

The type section of the Canol Formation (Devonian black shale) at Powell Creek: Critical assessment and correlation in the northern Cordillera, NWT, Canada

Abstract The Canol Formation is only 24.5 m thick at its historic type section at Powell Creek, northern Mackenzie Mountains, whereas in the off-bank sections of the Mackenzie Plain subsurface, where it is considered a high-quality shale hydrocarbon prospect, it thickens to 60–120 m. This paper reviews available lithological and conodont biostratigraphic information from the type section, discusses choices of contacts and subdivisions, and explores the limits of regional correlation using gamma spectrometry proxies. We position the base of the Canol Formation at the top of the lower resistant unit of the “allochthonous limestone beds”, the thick off-reef debris package present in this outcrop but absent in other well-known Canol sections. The base of the formation can be of a latest Givetian age as suggested by the norrisi zone conodont fauna from the “allochthonous limestone”. The top of the Canol Formation is placed at the base of a distinct, 2.1 m thick horizon with concretionary carbonate beds within the thick shale transition between the Canol and the Imperial formations. Limestone nodules from this horizon produced a conodont fauna that can occur in the jamieae to Upper rhenana zones (Frasnian zones 11–12) thereby suggesting a middle to earliest Late Frasnian age for the Canol top. The cross-section tying several outcrop and well sections across the regional facies zonation reveals that the Dodo Canyon Member, a unit erected in thick off-bank Canol sections, is traceable at Powell Creek. In this correlation, the Vermillion Creek Member, which is the lower portion of the Canol Formation in thick off-bank sections, finds its counterpart in the allochthonous limestone beds sensu MacKenzie (1970). This cross-section is the first correlation of the Canol stratotype at member level available in published sources. Thinness of the Canol Formation at Powell Creek, as well as its location in the carbonate bank toe-of-slope setting, are factors impairing its reference value and calling for more representative sections to act as reference sections and constitute a composite-stratotype for the Canol Formation.

Satellite image analysis of changes in glacier cover in Canada's northern Mackenzie Mountain Range (1987–2017)

The state of a group of glaciers in the northern Mackenzie Mountains across the Yukon‐Northwest Territories border was investigated over a period of three decades, using Landsat TM and OLI imagery from 1987, 1994, 1999, 2004, 2013, and 2017 to examine changes in glacier extents. A thresholded red/shortwave infrared band ratio image was used to delineate glacier boundaries. The total area of 74 glaciers in the study area decreased from 52.78 ± 1.32 km2 in 1987 to 24.89 ± 0.62 km2 in 2017, a loss of 27.89 ± 1.39 km2 or 52.8 ± 2.6%, with a mean rate of reduction of 1.8% · a−1. Smaller glaciers experienced larger relative changes in area. In this study, the rates of reduction are high compared to decreases reported for other glaciers in the region in the late 20th century. Based on linear extrapolation of the trend in values of total glacier area, it is predicted—subject to uncertainties in how glaciers diminish in size and eventually disappear—that the study area could be free of visible glacier cover within three decades.

Tortodus dodoensis, a new conodont species, and a Givetian (Middle Devonian) conodont fauna from the northern Mackenzie Mountains, northwest Canada

A new conodont species Tortodus dodoensis sp. nov. from the lower part of the Givetian (Middle Devonian) of the Mackenzie Mountains (NW Canada) is described. This paper also reports the lowest stratigraphic occurrence of a Givetian fauna containing a.o. Polygnathus amphora, P. denisbriceae, P. xylus ensensis, P. pseudoeiflius, P. linguiformis klapperi s.l., P. l. weddigei, P. parawebbi and P. pseudofoliatus from the northern Mackenzie Mountains. This fauna situates the sample in the timorensis to ansatus zones interval, possibly restricting it to the timorensis Zone. This result allows the positioning of the Eifelian–Givetian contact within the lowest 7.5 m of the Hare Indian Formation (Horn River Group) (northern Mackenzie Mountains, NW Territories).

Benthic biostratigraphy of the upper Eifelian (Devonian) Hume Formation at Hume River (type locality), northern Mackenzie Mountains, Northwest Territories, Canada

Benthic biostratigraphy of the upper Eifelian (Devonian) Hume Formation at Hume River (type locality), northern Mackenzie Mountains, Northwest Territories, Canada

Conodont biostratigraphy and T-R cycles of the Middle Devonian Hume Formation at Hume River (type locality), northern Mackenzie Mountains, Northwest Territories, Canada

Conodont biostratigraphy and T-R cycles of the Middle Devonian Hume Formation at Hume River (type locality), northern Mackenzie Mountains, Northwest Territories, Canada

Avian Communities of the Northern Mackenzie Mountains, Northwest Territories, Canada

Basic knowledge of the abundance and distribution of birds and their habitats and the relationships between them is limited for many parts of Arctic Canada, including montane regions. This information is important for conservation purposes as bird populations and habitats shift and as interest in development of northern areas increases. We characterized bird communities in the Mackenzie Mountains of the Northwest Territories by conducting point counts (n = 376) in June 2009 and 2010 and using community analysis metrics (multiple response permutation procedures, indicator species analysis, non-metric multidimensional scaling) to statistically and graphically describe bird data in six habitat types: coniferous forest, deciduous forest, shrub (short and tall), alpine tundra, and open water wetlands. Distinct habitats had significantly different bird communities, as shown by using multiple response permutation procedures (p < 0.005). Of 51 species, 32 had significant (p < 0.05) indicator values for one habitat type (n = 15) or groups of habitats (n = 17) in an indicator species analysis. The tall shrub habitat type had the most indicator species (six species) followed by alpine tundra (five species), then the combined conifer, deciduous, and wetland habitat group (four species) and the deciduous forest habitat types (three species). Species richness was highest in the tall shrub (n = 37), alpine (n = 30), and conifer and short shrub (n = 29) habitats. We also observed eight bird species not previously known to occur in the area, or which were outside published ranges. Our results highlight the variability in bird community composition between the major habitat types in the Mackenzie Mountains, serve as a baseline for future bird studies in the region, and underscore the need for more research in the area with impending anthropogenic changes.

Detrital zircon lineages of late Neoproterozoic and Cambrian strata, NW Laurentia

The Phanerozoic tectonic evolution of the Arctic is a field of escalating scientific interest. Detrital zircon provenance studies provide vital contributions to clarify the region’s tectonic evolution. Northwest Laurentia exposes a broad expanse of Proterozoic and Paleozoic sedimentary strata for which detrital zircon populations are poorly characterized. Moreover, the significance of sedimentary recycling is becoming better appreciated in light of detrital zircon studies. As more data become available, our understanding of the detrital zircon character of NW Laurentia improves, providing an increasingly reliable baseline at subcontinental resolution against which potentially allochthonous terranes, such as Arctic Alaska, can be assessed. Sandstones of late Neoproterozoic and Cambrian age from NW Canada yield detrital zircon signatures dominated by zircon grains recycled from Proterozoic sedimentary strata. Two Neoproterozoic sandstones from the northern Mackenzie Mountains yield zircon populations sourced from the Mackenzie Mountains Supergroup. Two Lower Cambrian sandstones sourced from the Yukon stable block and deposited in Richardson Trough have zircon populations nearly identical to those of the upper Wernecke Supergroup, locally exposed across the southern Yukon stable block, where they are unconformably overlain by Cambrian strata. Comparisons with similar studies from NW Canada permit generalizations of the patterns of zircon recycling. Four provenance lineages are described that characterize Laurentia-derived successions in NW Canada.

Slope and Submarine Fan Turbidite Facies of the Upper Devonian Imperial Formation, Northern Mackenzie Mountains, NWT

Research Article| June 01, 2009 Slope and Submarine Fan Turbidite Facies of the Upper Devonian Imperial Formation, Northern Mackenzie Mountains, NWT T. Hadlari; T. Hadlari Northwest Territories Geoscience Office, 4601-B, 52nd Avenue, Yellowknife, NWT, X1A 2R3 thomas_hadlari@gov.nt.ca 1Current Address: Geological Survey of Canada, 3303 - 33rd Street NW, Calgary, AB T2L 2A7, thomas.hadlari@nrcan-rncan.gc.ca Search for other works by this author on: GSW Google Scholar S.A. Tylosky; S.A. Tylosky University of Alberta, Department of Earth and Atmospheric Sciences, 1-26 Earth Sciences Building, Edmonton, AB T6G 2E3 Search for other works by this author on: GSW Google Scholar Y. Lemieux; Y. Lemieux Geological Survey of Canada, c/o Northwest Territories Geoscience Office, 4601-B, 52nd Avenue, Yellowknife, NWT X1A 2R3 Search for other works by this author on: GSW Google Scholar W.G. Zantvoort; W.G. Zantvoort Northwest Territories Geoscience Office, 4601-B, 52nd Avenue, Yellowknife, NWT X1A 2R3 Search for other works by this author on: GSW Google Scholar O. Catuneanu O. Catuneanu University of Alberta, Department of Earth and Atmospheric Sciences, 1-26 Earth Sciences Building, Edmonton, AB T6G 2E3 Search for other works by this author on: GSW Google Scholar Bulletin of Canadian Petroleum Geology (2009) 57 (2): 192–208. https://doi.org/10.2113/gscpgbull.57.2.192 Article history received: 18 Aug 2008 accepted: 30 Mar 2009 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation T. Hadlari, S.A. Tylosky, Y. Lemieux, W.G. Zantvoort, O. Catuneanu; Slope and Submarine Fan Turbidite Facies of the Upper Devonian Imperial Formation, Northern Mackenzie Mountains, NWT. Bulletin of Canadian Petroleum Geology 2009;; 57 (2): 192–208. doi: https://doi.org/10.2113/gscpgbull.57.2.192 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of Canadian Petroleum Geology Search Advanced Search Abstract At the front of the Mackenzie Mountains west of Norman Wells, the Upper Devonian Imperial Formation was deposited by a fan-slope complex that prograded southwest from an eastern basin margin. Laterally extensive submarine fan deposits are composed of intercalated sandstone lobe and lobe fringe deposits. Sandstone lobes are composed of thick-bedded turbidites reflecting high sediment fallout rates. Lobe fringe deposits are thin-bedded turbidites deposited under upper flow regime conditions. Slope facies are shale-dominant, but include turbidites deposited by both fine-grained dilute flows and thin-bedded facies deposited under upper flow regime conditions but low sediment fallout rates. Near the eastern edge of the study area, at Imperial River, shallow marine deposits are preserved above and below slope deposits, a relationship interpreted to record local shelf construction at the basin margin during initial stages of subsidence. Near the western edge of the study area, at Flyaway Creek, Imperial Formation is composed entirely of shale, marking the western extent of well developed base-of-slope submarine fan deposits. In the western area Imperial Formation is overlain by Tuttle Formation sandstone, which marks an increase in the grain size of sediment supplied to the southwestward prograding slope system. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Stress in western Canada from regional moment tensor analysis

More than 180 regional moment tensor (RMT) solutions for moderate-sized earthquakes (M ≥ 4) are used to examine the contemporary stress regime of western Canada and provide valuable information relating to earthquake hazard analysis. The overall regional stress pattern shows mainly NE–SW-oriented P axes for most of western Canada with local variations. In the northern cordillera, the maximum compressive stress direction (σ1) varies from east–west to north–south to NE–SW from south to north. The stress direction σ1 is consistent with the P axis direction for the largest earthquakes, except in the central and northern Mackenzie Mountains where there is a 16° difference. The Yakutat collision zone shows a steady change in σ1 from east–west in the east to north–south in the west. In the Canada – United States border region, RMT solutions suggest a north–south compressional regime may extend through southern British Columbia and northern Washington to the eastern Cordillera. In the Vancouver Island – Puget Sound region, RMT solutions do not show any obvious pattern in faulting style. However, the stress results are consistent with margin-parallel compression in the crust and downdip tension in the subducting slab. Along the Queen Charlotte fault σ1 is oriented ~45° to the strike of the northern section of the fault, which is dominated by strike-slip faulting, and ~60° to the strike of the southern section, which is dominated by high-angle thrust faults. The amount of thrust faulting infers a significant amount of convergence between the Pacific and North America plates in the southern Queen Charlotte Islands region.

Precambrian biota from the Little Dal Group, Mackenzie Mountains, northwestern Canada

Well preserved Precambrian algal microfossils and megafossils have been recovered in the northern Mackenzie Mountains from several levels and localities in a basinal, limestone-dominated rhythmite formation of the Little Dal Group. The microbiota includes the filaments Archaeotrichion, Taeniatum and Siphonophycus, and the sphaeromorph acritarchs Kildinella, Trachysphaeridium, Nucellosphaeridium, and Chuaria circularis. The megafossils, ail of probable algal affinities, comprise large carbonaceous ribbons assigned to the new vendotaenid species Tawuia dalensis n.g. n. sp., and the irregular compressions Mariana? antiqua and Beltina danai. The same formation has also yielded a dubiofossil probably representing traces on bedding planes made by small cylindrical, discoid, or spheroidal organisms, questionably referred toBergaueria. The biota suggests a late Helikian to early Hadrynian age (1.1–0.8 Ga) for the Little Dal Group, and adds to the growing body of evidence for the existence of eucaryotic organisms at that time.