scholarly journals Field data, till composition, and ice-flow history, south Rae Craton, Northwest Territories: results from the GEM-2 South Rae project - Surficial Mapping activity

2020 ◽  
Author(s):  
J E Campbell ◽  
M W McCurdy ◽  
G Lauzon ◽  
D Regis ◽  
M Wygergangs
2021 ◽  
Author(s):  
J E Campbell ◽  
I McMartin ◽  
M W McCurdy ◽  
P -M Godbout ◽  
T Tremblay ◽  
...  

1979 ◽  
Vol 16 (1) ◽  
pp. 60-72 ◽  
Author(s):  
J. P. N. Badham

Two alkaline igneous complexes and three lines of diatreme breccias were emplaced in the East Arm of Great Slave Lake during the lower Proterozoic. Field relationships suggest that those rocks are broadly cogenetic and were emplaced about 2.1 Ga ago.One of the intrusions, the Easter Island dyke, was rotated subsequent to emplacement such that both top and bottom are now exposed. Field and petrographic data are indicative of progressive differentiation along (i.e., up) the dyke and are substantiated by chemical data. The differentiation history of the early gabbros of the Blachford Lake complex is similar. Late differentiates of both complexes closely resemble the igneous matrices of the breccias and petrographic and chemical data support the proposal of cogenesis and contemporaneity.The field data show that there was a period of significant faulting and concomitant alkaline igneous activity in the East Arm area in the lower Proterozoic.


2007 ◽  
Vol 47 (2) ◽  
pp. 133-145 ◽  
Author(s):  
Arthur S. Dyke

ABSTRACT 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.


2008 ◽  
Vol 45 (5) ◽  
pp. 593-610 ◽  
Author(s):  
Jan M. Bednarski

The Laurentide Ice Sheet reached the Canadian Cordillera during the last glacial maximum in northeastern British Columbia and adjacent Northwest Territories and all regional drainage to unglaciated areas in the north was dammed by the ice. Converging ice-flow patterns near the mountain front suggest that the Laurentide Ice Sheet likely coalesced with the Cordilleran Ice Sheet during the last glaciation. With deglaciation, the ice masses separated, but earlier ice retreat in the south meant that meltwater pooled between the mountain front and the Laurentide margin. The level of the flooding was controlled by persistent ice cover on the southern Franklin Mountains. Glacial Lake Liard formed when the Laurentide Ice Sheet retreated east of the southern Liard Range and, at its maximum extent, may have impounded water at least as far south as the Fort Nelson River. Deglaciation of the plains was marked by local variations in ice flow caused by a thin ice sheet becoming more affected by the topography and forming lobes in places. These lobes caused diversions in local drainage readily traced by abandoned meltwater channels. Radiocarbon ages from adjacent areas suggest the relative chronology of deglaciation presented here occurred between 13 and 11 ka BP.


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