scholarly journals Neoproterozoic-Cambrian stratigraphy of the Mackenzie Mountains, northwestern Canada, part I: Ediacaran measured sections and updated lithostratigraphy, NE Sekwi Mountain map area (NTS 105-P)

2020 ◽  
Author(s):  
R B MacNaughton
Keyword(s):  
1978 ◽  
Vol 15 (7) ◽  
pp. 1205-1207 ◽  
Author(s):  
Douglas A. Archibald ◽  
Alan H. Clark ◽  
Edward Farrar ◽  
U Khin Zaw

K–Ar dating of magmatic biotite, and of hydrothermal biotite and muscovite, demonstrates that quartz monzonite intrusion and exoskarn scheelite mineralization at Cantung, N.W.T., took place over a brief interval in the Upper Cretaceous (ca. 91 Ma). The regional age relationships of magmatic and ore-forming activity in the Logan–Mackenzie Mountains are poorly defined, but it is tentatively inferred that tungsten mineralization may have been related to a late stage in the plutonic development of the area.


1984 ◽  
Vol 48 (1) ◽  
pp. 156 ◽  
Author(s):  
N. M. Simmons ◽  
M. B. Bayer ◽  
L. O. Sinkey

1990 ◽  
Vol 27 (1) ◽  
pp. 129-144 ◽  
Author(s):  
P. K. Kaiser ◽  
J. V. Simmons

The transport mechanism of some rock avalanches of the Mackenzie Mountains in the Yukon and Northwest Territories of Canada is reassessed on the basis of evidence collected during fieldwork and by comparison with results from numerical simulations of the debris flow mechanism. A new hypothesis of glaciation-related transport is advanced as an alternate explanation of apparently very mobile rock avalanches with anomalous travel distances. By the example of the Avalanche Lake slide, it is demonstrated that the debris was most likely not deposited on the current topography but on valley glacier ice at an elevation of about 400–500 m above the valley bottom. This conclusion is supported by field evidence, an empirical runup relationship, and the results from numerical flow simulations. A qualitative interpretation of other debris deposits suggests that several events in the Mackenzie Mountains can be interpreted in the same manner. Key words: rock avalanches, rock slides, debris transport, debris flow modelling, Mackenzie Mountains, Northwest Territories.


2006 ◽  
Vol 43 (12) ◽  
pp. 1791-1820 ◽  
Author(s):  
D E Jackson ◽  
A C Lenz

Four graptolite biozones are recorded from the Arenig portion of the Road River Group in the Richardson and Mackenzie mountains in the Yukon and Northwest Territories. In ascending order, these zones are Tetragraptus approximatus, Pendeograptus fruticosus, Didymograptus bifidus, and Parisograptus caduceus australis (new). The Castlemainian stage may be represented by nongraptolitic massive bedded chert. The Arenig–Llanvirn boundary is drawn below the first occurrence of Undulograptus austrodentatus. Fifty-four graptolite taxa are present, and 16 of these species and subspecies are recorded for the first time in this deep-water biotope, namely, Didymograptus? cf. adamantinus, D. asperus, D. dilatans, D. cf. kurcki, D. validus communis, Holmograptus aff. leptograptoides, H. sp. A, Isograptus? sp. nov. A, I. ? dilemma, Keblograptus geminus, Pseudisograptus manubriatus harrisi, Ps. m. koi, Ps. m. janus, Ps. cf. tau, Xiphograptus lofuensis, and Zygograptus cf. abnormis.


1996 ◽  
Vol 33 (6) ◽  
pp. 896-903 ◽  
Author(s):  
R. W. Barendregt ◽  
R. J. Enkin ◽  
J. Baker ◽  
A. Duk-Rodkin

The Mackenzie Mountains were affected by montane valley glaciers during the Pleistocene and peripherally by the Laurentide Ice Sheet during the last glaciation. In this paper we report on magnetostratigraphic dating and correlation of three sections recording Late Pliocene to Late Pleistocene glaciations: Katherine Creek, Little Bear River, and Inlin Brook (located around 65°N, 127°W). Each section consists of a colluvial unit overlying a Pliocene pediment surface cut into Proterozoic or Paleozoic bedrock, or Tertiary gravel, which is in turn overlain by a stack of five, and in places six, montane tills, usually with soils developed at their surfaces, and capped by a Laurentide till. Normal and reversed magnetizations were recognized with single-domain magnetite as a dominant remanence carrier. The Katherine Creek section has a normally magnetized colluvium at its base, which is overlain by two reversed tills, succeeded by three normal tills. We interpret the top two tills to be of Brunhes age (< 780 ka) but argue that the lowermost normal till is of probable Olduvai age (ca. 1.8 Ma). The two underlying tills are of Matuyama age (2.6 Ma to 780 ka), and the colluvial base is assigned to the Gauss (3.5–2.6 Ma). The Little Bear River section exposes a stratigraphic record similar to that found at Katherine Creek. Only four units could be assigned a paleomagnetic polarity, the others yielding incoherent results. Paleosols on the first and second till units were reversed and normal, respectively, and the top till was normal. Thus there is clear evidence of an older (reversed) Pleistocene glaciation and a magnetostratigraphic record compatible with that found at Katherine Creek. Magnetic measurements from Inlin Brook gave largely incoherent results, with the exception of the surface (Laurentide) till, which is normal. The glacial history recorded in the Mackenzie Mountains correlates well with other studies carried out in the Cordillera. The large-scale changes in climate revealed in these terrestrial records provide baseline data for paleoenvironmental reconstruction.


1978 ◽  
Author(s):  
J D Aitken ◽  
D G F Long ◽  
M A Semikhatov
Keyword(s):  

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