Rb–Sr contribution to the location of Churchill–Superior boundary in Manitoba

1970 ◽  
Vol 7 (3) ◽  
pp. 1017-1020
Author(s):  
A. Turek ◽  
Z. E. Peterman
Keyword(s):  
Drill Hole ◽  
Hudson Bay ◽  
The South ◽  
Lake Winnipeg ◽  
Hudson Bay Lowlands ◽  
Area North ◽  
Age Determinations

Eight whole-rock Rb–Sr age determinations on basement cores from the Hudson Bay Lowlands define an isochron of 1975 ± 45 m.y. (λRb = 1.39 × 10−11y−1) with an initial 87Sr/88Sr 0.7018 ± 0.0005. The indicated age is characteristic of the Churchill Province and on this basis Would suggest that the boundary between the Churchill and Superior provinces is to the south of the drill hole location. A similar age, 1925 ± 105 m.y. with an initial 87Sr/86Sr 0.7025 ± 0.0007, has been obtained on six whole-rock basement samples from the Minago River – Har-grave River area north of Lake Winnipeg.

Correlation of sea-level curves for the Lower Silurian of the Bruce Peninsula and Lake Timiskaming District (Ontario)

1982 ◽  
Vol 19 (5) ◽  
pp. 962-974 ◽  
Author(s):  
Valerie R. Colville ◽  
Markes E. Johnson
Keyword(s):  
Great Lakes ◽  
Sea Level ◽  
Hudson Bay ◽  
Strong Correlations ◽  
The South ◽  
Upper Peninsula ◽  
Level Curves ◽  
Lower Silurian ◽  
Hudson Bay Lowlands ◽  
Open Connection

Paleobathymetric interpretation of strata from the Bruce Peninsula and Lake Timiskaming District of Ontario shows strong correlations with data from the Michigan Upper Peninsula and Ontario's Manitoulin Island. Three to four cycles of fluctuating sea level occurred during Early Silurian (Llandoverian) time throughout much of the northern Great Lakes area, and involved the highly regular replacement of ostracode–vermiform, coral–algal, and pentamerid communities by one another. Although exposure is more limited than on Manitoulin Island or the Michigan Upper Peninsula, important clues regarding Early Silurian geography are found in strata of the Bruce Peninsula and Lake Timiskaming District. Continued thinning of stratigraphic units and an increased incidence of disconformities from north to south on the Bruce Peninsula suggest the episodic rise of the Algonquin Arch farther to the south and west. Contrary to earlier paleogeographic reconstructions, the patterns of community changeovers preserved in the Silurian outlier of the Lake Timiskaming District indicate a persistent, open connection between the seas of the northern Great Lakes area and the Hudson Bay Lowlands. This interpretation is more in keeping with recent paleontologic work on faunal distributions.

The Archaean Atâ intrusive complex (Atâ tonalite), north-east Disko Bugt, West Greenland

1999 ◽  
pp. 103-112
Author(s):  
Feiko Kalsbeek ◽  
Lilian Skjernaa
Keyword(s):  
Intrusive Complex ◽  
The South ◽  
Original Series ◽  
Early Proterozoic ◽  
West Greenland ◽  
North East ◽  
The North ◽  
Southern Border ◽  
Area North ◽  
Igneous Layering

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Kalsbeek, F., & Skjernaa, L. (1999). The Archaean Atâ intrusive complex (Atâ tonalite), north-east Disko Bugt, West Greenland. Geology of Greenland Survey Bulletin, 181, 103-112. https://doi.org/10.34194/ggub.v181.5118 _______________ The 2800 Ma Atâ intrusive complex (elsewhere referred to as ‘Atâ granite’ or ‘Atâ tonalite’), which occupies an area of c. 400 km2 in the area north-east of Disko Bugt, was emplaced into grey migmatitic gneisses and supracrustal rocks. At its southern border the Atâ complex is cut by younger granites. The complex is divided by a belt of supracrustal rocks into a western, mainly tonalitic part, and an eastern part consisting mainly of granodiorite and trondhjemite. The ‘eastern complex’ is a classical pluton. It is little deformed in its central part, displaying well-preserved igneous layering and local orbicular textures. Near its intrusive contact with the overlying supracrustal rocks the rocks become foliated, with foliation parallel to the contact. The Atâ intrusive complex has escaped much of the later Archaean and early Proterozoic deformation and metamorphism that characterises the gneisses to the north and to the south; it belongs to the best-preserved Archaean tonalite-trondhjemite-granodiorite intrusions in Greenland.

Constraining the age of the last interglacial–glacial transition in the Hudson Bay lowlands (Canada) using U–Th dating of buried wood

2012 ◽  
Vol 7 ◽  
pp. 37-47 ◽  
Author(s):  
G. Allard ◽  
M. Roy ◽  
B. Ghaleb ◽  
P.J.H. Richard ◽  
A.C. Larouche ◽  
...  
Keyword(s):  
Hudson Bay ◽  
Last Interglacial ◽  
Hudson Bay Lowlands

New Complexities in Zoogeography and Taxonomy of the Pygmy Whitefish (Prosopium coulteri)

1972 ◽  
Vol 29 (12) ◽  
pp. 1772-1775 ◽  
Author(s):  
C. C. Lindsey ◽  
W. G. Franzin
Keyword(s):  
River System ◽  
Yukon Territory ◽  
Hudson Bay ◽  
The South ◽  
Bristol Bay ◽  
River Drainage ◽  
Bay Area ◽  
First Time ◽  
Mackenzie River

Pygmy whitefish (Prosopium coulteri) are recorded for the first time from the Peel–Mackenzie river drainage (Elliott Lake, Yukon Territory) and from the Hudson Bay drainage (Waterton Lakes, Alberta, in the South Saskatchewan–Nelson river system). The morphology of specimens from both localities contradicts the previously known pattern of a southeastern "low-rakered" and a northwestern "high-rakered" form (with the two forms occurring sympatrically in some lakes of the Bristol Bay area). Specimens from Elliott Lake, the most northerly known locality, resemble the southeastern form and those from Waterton Lakes the northwestern form. Both Waterton and Elliott lakes lie close to unglaciated refugia, suggesting that the species may have survived Wisconsin glaciation and diverged in several different watersheds.

scholarly journals Recent Explorations to the South of Hudson Bay: Discussion

1897 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Admiral Wharton ◽  
Colonel Harris ◽  
Dr. Bell
Keyword(s):  
Hudson Bay ◽  
The South

scholarly journals Bird trends from long-term observation data at sites in the Hudson Bay Lowlands

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Rodney W. Brook ◽  
Lisa A. Pollock ◽  
Kenneth F. Abraham ◽  
Glen S. Brown
Keyword(s):  
Hudson Bay ◽  
Observation Data ◽  
Hudson Bay Lowlands ◽  
Long Term Observation
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