Two Assemblages of Marine Algae from Post-Glacial Deposits in the Eastern Canadian Arctic

1972 ◽  
Vol 9 (1) ◽  
pp. 109-115 ◽  
Author(s):  
W. I. Illman ◽  
J. McLachlan ◽  
T. Edelstein
Keyword(s):  
Marine Algae ◽  
Canadian Arctic ◽  
Species Assemblages ◽  
Hudson Bay ◽  
Baffin Island ◽  
Glacial Deposits ◽  
Eastern Canadian Arctic

The marine algae of the post-glacial deposits from the Ottawa Islands, Hudson Bay and Broughton Island off East Baffin Island were examined. A total of 15 non-calcareous species were identified, of which the most abundant at both sites were Sphacelaria plumosa and Desmarestia aculeata. The species assemblages are characteristic of present-day arctic and subarctic floras.

Late glacial ice margins and deglacial chronology for southeastern Baffin Island and Hudson Strait, eastern Canadian Arctic

1992 ◽  
Vol 29 (5) ◽  
pp. 1000-1017 ◽  
Author(s):  
Jay A. Stravers ◽  
Gifford H. Miller ◽  
Darrell S. Kaufman
Keyword(s):  
Canadian Arctic ◽  
Late Glacial ◽  
Hudson Bay ◽  
Baffin Island ◽  
Radiocarbon Dates ◽  
Glacial Ice ◽  
Sea Levels ◽  
Molluscan Fauna ◽  
Rising Sea Levels ◽  
Eastern Canadian Arctic

Radiocarbon dates from marine piston cores and from onshore raised marine stratigraphic sections in the Hudson Strait region were used to reconstruct deglacial isochrons for 9900, 9500, 8800–8500, and 8000 BP. At the culmination of the Gold Cove readvance (9900 BP), Labrador–Ungava ice flowed northeastward across Hudson Strait and outer Frobisher Bay and stood for the last time on the Baffin Island continental shelf. Subsequent retreat by calving was rapid and profound, opening the entire Hudson Strait marine trough by 9500 BP. At this time, ice dispersal from Foxe Basin, Labrador–Ungava, and local ice on Meta Incognita Peninsula supported tidewater margins along much of the coastline, with the exception of northernmost Ungava Peninsula, where the ice margin stabilized onshore. This onshore margin remained in place throughout the Cockburn Substage while a major northeastward readvance of Ungava Bay ice (the Noble Inlet readvance from 8800 to 8500 BP) crossed outer Hudson Strait, grounding on the Hudson Strait sill and the south coast of Meta Incognita Peninsula. Sedimentation continued in an enclosed basin in western Hudson Strait, but marine circulation was prohibited by the ice dam, and upper water column salinities became too low to support a marine molluscan fauna. Ungava Bay ice was not thick enough to sustain flow across eastern Hudson Strait, and rising sea levels soon destroyed the Noble Inlet ice dam. By 8300 BP normal marine waters were circulating in eastern Hudson Strait, followed shortly thereafter (at 8100 BP) by the deglaciation of western Hudson Strait and Hudson Bay.

Conodont paleontology and biostratigraphy of Ordovician carbonates and petroliferous carbonates on Southampton, Baffin, and Akpatok islands in the eastern Canadian Arctic

1989 ◽  
Vol 26 (10) ◽  
pp. 1880-1903 ◽  
Author(s):  
Alexander D. McCracken ◽  
Godfrey S. Nowlan
Keyword(s):  
Canadian Arctic ◽  
Bedding Plane ◽  
Baffin Island ◽  
Jordan River ◽  
Oil Shales ◽  
Age Range ◽  
Eastern Canadian Arctic

Carbonate and petroliferous carbonate units ("oil shales") on Southampton, Baffin, and Akpatok islands have yielded a total of 2277 conodonts, the more biostratigraphically useful of which indicate not all units are correlative. The Boas River "shale", the lower of the two petroliferous units on Southampton Island, overlies the Bad Cache Rapids Group and contains a diverse fauna, including elements of Amorphognathus ordovicicus Branson and Mehl. Previous reports have indicated the presence of Culumbodina penna Sweet, a species whose range only barely overlaps that of A. ordovicicus in the middle Maysvillian. Carbonate beds and bedding-plane surfaces of the higher Red Head Rapids Formation at Sixteen Mile Brook yielded A. ordovicicus faunas containing Aphelognathus cf. A. divergens Sweet. These beds are likely Richmondian, since A. divergens is known elsewhere only from Richmondian strata. A metasicula of "Glyptograptus" hudsoni Jackson, several natural conodont assemblages, and fused enigmatic coniform elements were also found at Sixteen Mile Brook.The petroliferous unit in unnamed strata at Amadjuak Lake on Baffin Island contains Belodina area Sweet, which is indicative of a late Edenian to early Maysvillian age. Conodonts from the petroliferous strata at Jordan River on Baffin Island suggest a Trentonian to early Maysvillian age. The conodonts recovered from unnamed strata on Akpatok Island are not very diagnostic but indicate an age range from Shermanian to Gamachian.

scholarly journals A first assessment of microplastics and other anthropogenic particles in Hudson Bay and the surrounding eastern Canadian Arctic waters of Nunavut

FACETS ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 432-454 ◽  
Author(s):  
Aimee Huntington ◽  
Patricia L. Corcoran ◽  
Liisa Jantunen ◽  
Clara Thaysen ◽  
Sarah Bernstein ◽  
...  
Keyword(s):  
Surface Water ◽  
Long Range ◽  
Canadian Arctic ◽  
The Arctic ◽  
Long Range Transport ◽  
Human Populations ◽  
Hudson Bay ◽  
Arctic Ecosystems ◽  
Range Transport ◽  
Eastern Canadian Arctic

Microplastics are a globally ubiquitous contaminant, invading the most remote regions, including the Arctic. To date, our understanding of the distribution and sources of microplastics in the Arctic is limited but growing. This study aims to advance our understanding of microplastics in the Arctic. Surface water, zooplankton, sediment, and snow samples were collected from Hudson Bay to north Baffin Bay onboard the CCGS Amundsen from July to August 2017. Samples were examined for microplastics, which were chemically identified via Raman spectroscopy for surface water and zooplankton and Fourier transform infrared spectroscopy for sediment. We found that 90% of surface water and zooplankton samples, and 85% of sediment samples, contained microplastics or other anthropogenic particles. Mean anthropogenic particle concentrations, which includes microplastics, were 0.22 ± 0.23 (per litre) for surface water, 3.51 ± 4.00 (per gram) for zooplankton, and 1.94 ± 4.12 (per gram) for sediment. These concentrations were not related to the human populations upstream, suggesting that microplastic contamination in the Arctic is from long-range transport. Overall, this study highlights the presence of microplastics across the eastern Canadian Arctic, in multiple media, and offers evidence of long-range transport via ocean and atmospheric currents. Further research is needed to better understand sources, distribution, and effects to Arctic ecosystems.

scholarly journals Breeding and Non-Breeding Range of Canada, Branta canadensis, and Cackling Geese, Branta hutchinsii, in the Eastern Canadian Arctic

2005 ◽  
Vol 119 (4) ◽  
pp. 483
Author(s):  
Mark L. Mallory ◽  
Alain J. Fontaine ◽  
Hugh Boyd
Keyword(s):  
Canadian Arctic ◽  
Branta Canadensis ◽  
Evidence Based ◽  
Canada Geese ◽  
Baffin Island ◽  
Chen Caerulescens ◽  
Branta Canadensis Interior ◽  
Cackling Geese ◽  
Distributional Knowledge ◽  
Eastern Canadian Arctic

The accepted breeding distribution of Canada Geese from the Atlantic Population (Branta canadensis interior) in the eastern Canadian Arctic is currently confined to northern Québec and the south coast of Baffin Island. Here we provide evidence based on observations from scientific studies, Inuit hunters, and territorial Wildlife Officers that B. c. interior now breeds in growing numbers 500 km farther north on northeastern Baffin Island than previously reported. Cackling Geese (B. hutchinsii), which breed more widely across eastern Arctic Canada, to about 72°N, may also be increasing there. Moreover, individuals of both species are seen occasionally as far north as Ellesmere Island in small flocks and within migrating or moulting flocks of Snow Geese (Chen caerulescens) or Brant (B. bernicla hrota), though none of these far northern stragglers are known to have bred. Whether these observations reflect a recent range expansion or improved distributional knowledge from more intensive recent survey efforts remains unknown.

scholarly journals GIS analyses of ice-sheet erosional impacts on the exposed shield of Baffin Island, eastern Canadian Arctic

2015 ◽  
Vol 52 (11) ◽  
pp. 966-979 ◽  
Author(s):  
Karin Ebert
Keyword(s):  
Ice Sheet ◽  
Canadian Arctic ◽  
Laurentide Ice Sheet ◽  
Baffin Island ◽  
Glacial Erosion ◽  
Ice Sheet Erosion ◽  
The Impact ◽  
Exposure Ages ◽  
Eastern Canadian Arctic ◽  
Sheet Erosion

The erosional impacts of former ice sheets on the low-relief bedrock surfaces of Northern Hemisphere shields are not well understood. This paper assesses the variable impacts of glacial erosion on a portion of Baffin Island, eastern Canadian Arctic, between 68° and 72°N and 66° and 80°W. This tilted shield block was covered repeatedly by the Laurentide Ice Sheet during the late Cenozoic. The impact of ice-sheet erosion is examined with GIS analyses using two geomorphic parameters: lake density and terrain ruggedness. The resulting patterns generally conform to published data from other remote sensing studies, geological observations, cosmogenic exposure ages, and the distribution of the chemical index of alteration for tills. Lake density and terrain ruggedness are thereby demonstrated to be useful quantitative indicators of variable ice-sheet erosional impacts across Baffin Island. Ice-sheet erosion was most effective in the lower western parts of the lowlands, in a west–east-oriented band at around 350–400 m a.s.l., and in fjord-onset zones in the uplifted eastern region. Above the 350–400 m a.s.l. band and between the fjord-onset zones, ice-sheet erosion was not sufficient to create extensive ice-roughened or streamlined bedrock surfaces. The exception — where lake density and terrain ruggedness indicate that ice-sheet erosion had a scouring effect all across the study area — was in an area from Foxe Basin to Home Bay with elevations <400 m a.s.l. These morphological contrasts link to former ice-sheet basal thermal regimes during the Pleistocene. The zone of low glacial erosion surrounding the cold-based Barnes Ice Cap probably represents the ice cap’s greater extent during successive Pleistocene cold stages. Inter-fjord plateaus with few ice-sheet bedforms remained cold-based throughout multiple Pleistocene glaciations. In contrast, zones of high lake density and high terrain ruggedness are a result of the repeated development of fast-flowing, erosive ice in warm-based zones beneath the Laurentide Ice Sheet. These zones are linked to greater ice thickness over western lowland Baffin Island. However, adjacent lowland surfaces with similar elevations of non-eroded, weakly eroded, and ice-scoured shield bedrock indicate that—even in areas of high lake density and terrain ruggedness—the total depth of ice sheet erosion did not exceed 50 m.

Morphological characterization of submarine slope failures in a semi-enclosed fjord, Frobisher Bay, eastern Canadian Arctic

2018 ◽  
Vol 477 (1) ◽  
pp. 367-376 ◽  
Author(s):  
Robert Deering ◽  
Trevor Bell ◽  
Donald L. Forbes ◽  
Calvin Campbell ◽  
Evan Edinger
Keyword(s):  
Flow Characteristics ◽  
Canadian Arctic ◽  
Morphological Characterization ◽  
Rapid Expansion ◽  
Baffin Island ◽  
Slope Failures ◽  
Submarine Slope ◽  
Relative Chronology ◽  
Arctic Fjord ◽  
Eastern Canadian Arctic

AbstractSubmarine slope failures in the nearshore waters of SE Baffin Island, eastern Canadian Arctic, present a challenge to coastal and seabed development. Submarine slope failures are a known geohazard in fjords in Norway, Chile, Alaska, British Columbia and elsewhere, but have received little attention in the coastal waters of Arctic Canada. Over the past 6 years, there has been a rapid expansion of multibeam echosounder (MBES) mapping in Canadian Arctic fjords, leading to the discovery of many submarine slope failures. One area that has been mapped in detail is inner Frobisher Bay. This macrotidal, seasonally ice-covered, semi-enclosed embayment has a glacially scoured bed, ice-contact deposits, including recessional moraines, and stratified glaciomarine and post-glacial silts and clays with abundant dropstones. The prevalence of submarine slope failures in the inner bay (one per 20 km2) appears to be anomalous. To date, MBES mapping has imaged at least 246 failures, ranging in size from 0.007 to 2.1 km2 and all within the glaciomarine and post-glacial succession. Morphometric analysis of these features based on high-resolution MBES bathymetry provides an insight into their spatial distribution, relative chronology, triggers and flow characteristics; factors essential to understanding the mechanisms underlying their abundance in this Canadian Arctic fjord.

Etching of Hornblende Grains in Arctic Soils: An Indicator of Relative Age and Paleoclimate

1979 ◽  
Vol 11 (2) ◽  
pp. 197-212 ◽  
Author(s):  
William W. Locke
Keyword(s):  
Soil Moisture ◽  
Canadian Arctic ◽  
Unfrozen Water ◽  
Soil Profiles ◽  
Baffin Island ◽  
Climatic Parameter ◽  
Relative Age ◽  
Arctic Soils ◽  
The Mean ◽  
Eastern Canadian Arctic

The degree of etching of hornblende grains in soils is defined as the mean depth of maximum etching on 100 grains per sample and is a function of: (1) the depth in the profile; (2) the age of the deposit on which the soil is formed; and (3) the climate since deposition. In soils formed on moraines in the eastern Canadian Arctic, etching decreases logarithmically with increasing depth in the profile, and the rate of etching at a given depth decreases logarithmically with increasing age. The most important climatic parameter with respect to etching appears to be the effective precipitation. Equally important in terms of soil moisture regimen is the presence of unfrozen water. Both affect the rate of etching as a function of depth and age. The inferred climate of northern Cumberland Peninsula, Baffin Island, N.W.T., Canada, preceding, during, and following the last (Foxe) glaciation, is indicated by the degree of etching of hornblende grains in soil profiles of various ages as follows: pre-Foxe—warm/wet; early to middle Foxe—mild/moist; middle to late Foxe—cold/arid; Hypsithermal—mild/moist; Neoglacial—cool/dry.

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