Precambrian geology of Boothia Peninsula, Somerset Island and Prince of Wales Island, district of Franklin

Blackadar, R G

doi:10.4095/101472

Cited by 9 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among all the islands in the Arctic Archipelago, it is one of the lowest in elevation, never rising 100 m above sea level (Fraser and Henock, 1959). The southeastern coastline, around the Gjoa Haven area, is made up of Ordovician and Silurian dolomite and dolomitic sandstone overlain by Pleistocene ice-contact sediments composed mainly of sand and gravel (Blackadar, 1967;Helie, 1984). Glacial sediments, including basal till, ablation moraine, ice-rafted boulders, and silts, are present across the island (Fraser and Henock, 1959).…”

Section: Study Sitesmentioning

confidence: 99%

Benthic Marine Fauna and Flora of Two Nearshore Coastal Locations in the Western and Central Canadian Arctic

Brown¹,

Edinger²,

Hooper³

et al. 2011

ARCTIC

View full text Add to dashboard Cite

ABSTRACT. Baseline data on nearshore benthic macrofauna and flora assemblages are necessary for successful environmental monitoring in the Arctic, where major climate and industrial changes are underway, yet to date these environments remain understudied. This study used bottom video and benthic grab samples to compare shallow benthic marine (1 -40 m) floral and faunal distribution and composition in two nearshore locations in the Canadian Arctic with different geomorphic settings. Sachs Harbour, located on southwestern Banks Island, has a submergent soft-sediment shoreline with locally rapid coastal erosion, while Gjoa Haven, located on southeastern King William Island, has an emergent shoreline dominated by coarse ice-contact Quaternary sediments with little to no coastal erosion. Gjoa Haven's sediment-starved, heterogeneous nearshore area contributes to a more diverse macroalgal flora than is found at Sachs Harbour, where a continuous supply of sand and mud from thermally driven coastal erosion and muddy runoff produces a more homogeneous nearshore environment. Seventy-four species (10 macroalgae, 64 macrofauna) were recorded from southwestern Banks Island and 65 species (26 macroalgae, 39 macrofauna) from southeastern King William Island. Species composition differed greatly among locations and varied significantly among substrate and depth classes for grab-and video-sampled biota at Gjoa Haven and among depth classes for bottom video biota at Sachs Harbour. Faunally barren, shallow, mobile sand sheets were the dominant habitat sampled in Sachs Harbour. Gjoa Haven's habitats differed significantly along a depth gradient, with sand and gravel substrates covered by Fucus sp. at depths shallower than 10 m and muddy substrates with filamentous green algae, Coccotylus truncatus, and cerianthid anemones inhabiting water down to 40 m.

show abstract

Section: Study Sitesmentioning

confidence: 99%

Benthic Marine Fauna and Flora of Two Nearshore Coastal Locations in the Western and Central Canadian Arctic

Brown¹,

Edinger²,

Hooper³

et al. 2011

ARCTIC

View full text Add to dashboard Cite

show abstract

“…This "grain" is, in fact, the modified compositional banding (So/S1). From the air it looks misleadingly undisturbed in some areas, and even on the ground the complexity of the structural geometry is not immediately apparent, owing to the size of the large-scale structures and the lack of lithic markers (see, for example, Blackadar 1967). However, three detailed structural traverses of the arch carried out by two of the present authors (R.L.B.…”

Section: Fig 2 Sketches Illustrating the Essential Relationships Ofmentioning

confidence: 85%

“…In keeping with this data a number of F2 eyefolds can be observed on airphotos of the region. The largest of them (previously recorded by Blackadar andChristie 1963, andby Blackadar 1967, as an elongate domal structure) lies just to the north of the Fitz Roy Inlet traverse line (locality 6 on Fig. 6).…”

Section: Fig 2 Sketches Illustrating the Essential Relationships Ofmentioning

confidence: 95%

“…A number of authors (Blackadar and Christie 1963;Kerr and Christie 1965;Blackadar 1967) have commented on the fact that the north-south structural "grain" of the basement rocks is parallel to the trend of the Boothia Arch itself. This "grain" is, in fact, the modified compositional banding (So/S1).…”

Section: Fig 2 Sketches Illustrating the Essential Relationships Ofmentioning

confidence: 97%

See 1 more Smart Citation

The structure, metamorphism, and development of the Boothia Arch, Arctic Canada

Brown¹,

Dalziel²,

Rust³

1969

Can. J. Earth Sci.

View full text Add to dashboard Cite

The Precambrian basement rocks of the Boothia Arch exhibit three phases of folding characteristic of deep-level deformation in mobile belts. Structural cross-sections demonstrate that the geometry of compositional layering and regionally parallel axial-plane foliation of first-phase folds is controlled primarily by structures of the second phase.The basement gneisses contain assemblages of the amphibolite-granulite transitional facies. The felsic gneisses exhibit a planar fabric clearly defined by nearly oblate quartz grains, usually considered to be typical of "granulite" facies rocks. In the Boothia Arch this foliation is an axial surface structure formed during the second fold phase. Fabric studies suggest that anhydrous assemblages stable in the granulite facies prior to the second phase of deformation were replaced during this phase by hydrous assemblages characteristic of the amphibolite-granulite transitional facies.The Boothia Arch was a source of clastic sediments during three periods of cover-rock deposition. It was a mild positive feature in Aston times (late Proterozoic or early Paleotoic), and was rapidly uplifted along north-south trends during late Silurian and early Devonian times to produce continental clastic facies of the Peel Sound Formation symmetrically related to the arch. The limited Cretaceous-Tertiary record suggests irregular uplift and localized deltaic sedimentation. At other times the Boothia Arch was insignificant as a source of detritus, and carbonates were deposited over the area.The north-south strike of compositional banding and axial surfaces of the first-and second-phase folds in the basement parallels the axis of the arch and axial surfaces of folds in the cover rocks. Also, fracture patterns in the basement and cover rocks are similar. Beyond this there is no obvious relationship between the internal structure of the basement and the later development of the arch.

show abstract

“…Granite and gneiss erratics are widespread and are undoubtedly of Laurentide origin. The red sandstone erratics, other than those in the vicinity of the one red sandstone outcrop area, are more likely of southern than local provenance; red sandstone crops out broadly on northern Prince of Wales and neighbouring islands (Blackadar, 1967;Dyke era/., 1992) and extends an unknown distance offshore toward Lowther Island. These sandstones were crossed by the northeastward Laurentide flowlines recorded by striae and ice moulded rock on Lowther Island.…”

Section: Géologie Des Formations Superficielles De Lowther Islandmentioning

confidence: 99%

Glacial and Sea Level History of Lowther and Griffith Islands, Northwest Territories: A Hint of Tectonics

Dyke¹

2007

gpq

View full text Add to dashboard Cite

Lowther and Griffith islands, in the centre of Parry Channel, were overrun by the Laurentide Ice Sheet early in the last glaciation. Northeastward Laurentide ice flow persisted across at least Lowther Island until early Holocene déglaciation. Well constrained postglacial emergence curves for the islands confirm a southward dip of raised shorelines, contrary to the dip expected from the ice load configuration. This and previously reported incongruities may indicate regionally extensive tectonic complications of postglacial rebound aligned with major structural elements in the central Canadian Arctic Islands.Les îles Lowther et Griffith, situées au centre du chenal de Parry, ont été recouvertes par l'Inlandsis laurentidien tôt au cours de la dernière glaciation. Un écoulement glaciaire vers le nord-ouest a persisté à l'île Lowther, tout au moins, jusqu'à la déglaciation au début de l'Holocène. Les courbes d'émersion bien identifiées de l'île confirment une inclinaison des plages soulevées vers le sud, contrairement à l'inclinaison prévue à partir de la configuration de la charge glaciaire. Ce fait ainsi que d'autres anomalies déjà signalées pourraient indiquer des complications d'ordre tectonique à l'échelle régionale au moment du relèvement isostatique postglaciaire correspondant aux principaux éléments structuraux des îles du centre de l'Arctique canadien.Die im Zentrum des Parry-Kanals gelegenen Insein Lowther und Griffith wurden zu Beginn der letzten Vereisung durch die laurentidische Eisdecke bedeckt. Der laurentidische EisfluB in Richtung Nordosten hat zumindest ùber die Insel Lowther hinweg bis zur frùhen Holozan-Enteisung gedauert. Die deutlich erkennbaren postglazialen Auftauchkurven der Insein bestâtigen eine Neigung der angehobenen Kùstenlinien nach Sùden, entgegen der Neigung, die man entsprechend der Eismassenkonfiguration erwartet hàtte. Dies und zuvor schon aufgezeigte Anomalien kônnten auf regional extensive tektonische Komplikationen beim postglazialen isostatischen Rùckprall hinweisen, entsprechend den wichtigsten strukturellen Elementen der Insein im Zentrum der kana-dischen Arktis

show abstract

Precambrian geology of Boothia Peninsula, Somerset Island and Prince of Wales Island, district of Franklin

Cited by 9 publications

References 0 publications

Benthic Marine Fauna and Flora of Two Nearshore Coastal Locations in the Western and Central Canadian Arctic

Benthic Marine Fauna and Flora of Two Nearshore Coastal Locations in the Western and Central Canadian Arctic

The structure, metamorphism, and development of the Boothia Arch, Arctic Canada

Glacial and Sea Level History of Lowther and Griffith Islands, Northwest Territories: A Hint of Tectonics

Contact Info

Product

Resources

About