Thickness records of glacial Lake Ojibway varves from Duparquet and Dufresnoy lakes, northwestern Quebec

Two overburden test holes drilled to bedrock in Currie Township, southwest of Matheson, Ontario, penetrated stratified beds containing fossil plant detritus resting on an oxidized substrate, which are between two till sheets underlying glacial Lake Ojibway-Barlow varved clays. The fossil plants, chiefly mosses, represent an environment that is common in the region today, and are radiocarbon dated (GSC-2148) as older than 37000 years. The interglacial deposit is tentatively correlated with the Missinaibi Formation in the Moose River basin of the James Bay lowlands, probably of Sangamon age.

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Iceberg furrows as paleowind indicators and icebergs as erosion and sedimentation agents in Glacial Lake Ojibway, Abitibi, Québec

10.4095/205754 ◽

1996 ◽

Cited By ~ 1

Author(s):

J J Veillette ◽

S J Paradis

Keyword(s):

Glacial Lake ◽

Lake Ojibway

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A model for the demise of large, glacial Lake Ojibway, Ontario and Quebec

Journal of Paleolimnology ◽

10.1007/s10933-013-9707-9 ◽

2013 ◽

Vol 50 (1) ◽

pp. 105-121 ◽

Cited By ~ 14

Author(s):

Justin S. Stroup ◽

Thomas V. Lowell ◽

Andy Breckenridge

Keyword(s):

Glacial Lake ◽

Lake Ojibway

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Insights into the Connaught sequence of the Timiskaming varve series from Frederick House Lake, northeastern Ontario

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2020-0217 ◽

2021 ◽

Author(s):

Gregory R. Brooks

Keyword(s):

Mass Transport ◽

Lake Ontario ◽

Circumstantial Evidence ◽

Glacial Lake ◽

Core Samples ◽

Acoustic Profile ◽

Lake Ojibway

A sub-bottom acoustic profile survey encountered a mass transport deposit (MTD) bed, 5-7 m thick, interbedded within glaciolacustrine deposits of glacial Lake Ojibway at Frederick House Lake, Ontario. Analysis of the thickness patterns of rhythmic couplets in recovered core samples revealed that the Connaught sequence, the youngest of the Timiskaming varve series, immediately under- and overlie the MTD. Comparison to regional published varve series reveals two possible interpretations for the varve numbering. One, varve(v) 2066 to v2115, requires the inference of a 55 varve year (vyr) disconformity just below the Connaught sequence, while alternative numbering, v2011a to v2060a (a – alternative), extends continuously from older varves. Circumstantial evidence supporting the alternative numbering is: i) the uncertainty of applying a common 55 vyr disconformity to three varve series located up to 23 km apart and which otherwise exhibit closely matching thickness plots; ii) the lack of evidence of an erosive unconformity in the sub-bottom acoustic profiles from Frederick House Lake; and iii) the uncertain varve count within a key part of the Matagami series, located abut 300 km away and from which the 55 vyr disconformity is extrapolated. At Frederick House Lake, the alternative numbering indicates that the maximum position of the Cochrane ice advance and the Connaught varves may be, in effect, contemporary in age. More broadly, the alternative numbering indicates that the youngest known varve that formed before the terminal drainage of glacial Lake Ojibway is v2074a rather than v2129 in the original numbering.

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Evidence of late glacial paleoseismicity from submarine landslide deposits within Lac Dasserat, northwestern Quebec, Canada

Quaternary Research ◽

10.1016/j.yqres.2016.06.005 ◽

2016 ◽

Vol 86 (2) ◽

pp. 184-199 ◽

Cited By ~ 18

Author(s):

Gregory R. Brooks

Keyword(s):

Ice Sheet ◽

Late Glacial ◽

Relative Strength ◽

Submarine Landslide ◽

Laurentide Ice Sheet ◽

Glacial Lake ◽

Event Horizons ◽

Lake Ojibway

AbstractAn integrated seismo- and chronostratigraphic investigation at Lac Dasserat, northwestern Quebec, identified 74 separate failures within eight event horizons. Horizons E and B, and H and G have strong or moderately-strong multi-landslide signatures, respectively, composed of 11-23 failures, while horizons F, D, C, and A have minor landslide signatures consisting of a single or pair of deposit(s). Cores collected at six sites recovered glacial Lake Ojibway varve deposits that are interbedded with the event horizons. The correlation of the varves to the regional Timiskaming varve series allowed varve ages or ranges of varve ages to be determined for the event horizons. Horizons H, G, E, and B are interpreted to be evidence of paleoearthquakes with differing levels of interpretative confidence, based on the relative strength of the multi-landslide signatures, the correlation to other disturbed deposits of similar age in the region, and the lack or possibility of alternative aseismic mechanisms. The four interpreted paleoearthquakes occurred between 9770 ± 200 and 8470 ± 200 cal yr BP, when glacial Lake Ojibway was impounded behind the Laurentide Ice Sheet during deglaciation. They probably represent an elevated period of seismicity at deglaciation that was driven by crustal unloading.

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Radiocarbon dates on peat and tree remains from James Bay area, subarctic Quebec

Canadian Journal of Forest Research ◽

10.1139/x79-023 ◽

1979 ◽

Vol 9 (1) ◽

pp. 125-129 ◽

Cited By ~ 8

Author(s):

Jean-Claude Dionne

Keyword(s):

Late Glacial ◽

Glacial Lake ◽

Before Present ◽

James Bay ◽

Radiocarbon Dates ◽

Bay Area ◽

Lake Ojibway ◽

James Bay Lowlands

14C dates on peat and tree remains from the southern part of James Bay Lowlands, subarctic Quebec, indicate that forests and peatland conditions began at least 1000 years after the deglaciation of the area. Inception of forest and organic deposition in bogs varies within the main geological events of the late-glacial and postglacial times in the area: the drainage of glacial Lake Ojibway, the Tyrrell Sea transgression, and the emergence. The oldest age recorded for the beginning of peat deposition is 6890 ± 120 years before present (BP) at an elevation of 240 m and the youngest age is 3830 ± 120 years BP at an elevation of 60 m. A delay ranging from 400 to 900 years between forest occupation and the establishment of bog conditions is recorded.

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Thickness record of varves from glacial Ojibway Lake recovered in sediment cores from Frederick House Lake, northeastern Ontario

10.4095/329275 ◽

2022 ◽

Author(s):

G R Brooks

Keyword(s):

Ct Scan ◽

Sediment Cores ◽

Lake Ontario ◽

Core Sample ◽

Glacial Lake ◽

Varve Thickness ◽

Core Samples ◽

Visual Comparison ◽

Original Interpretation ◽

Lake Ojibway

The thicknesses of 384 rhythmic couplets were measured along a composite sequence of glacial Lake Ojibway glaciolacustrine deposits recovered in two sediment cores from Frederick House Lake, Ontario. The visual comparison of distinctive couplets in the CT-scan radiographs of the Frederick House core samples to photographs of core samples from Reid Lake show a match of ±1 varve number from v1656-v1902, and ±5 varve numbers between v1903-v2010, relative to the regional numbering of the Timiskaming varve series. There are two interpretations for the post-v2010 couplets that fall within the Connaught varve sequence of the regional series. In the first, the interpreted numbering spans from v2066-v2115, which produces a gap of 55 missing varves equivalent to v2011-v2065, and corresponds to the original interpretation of the Connaught varve numbering. The second spans v2011a-v2060a, and represents alternative (a) numbering for the same varves. Varve thickness data are listed in spreadsheet files (.xlsx and .csv formats), and CT-Scan radiograph images of core samples are laid out on a mosaic poster showing the interpreted varve numbering and between-core sample correlations of the varve couplets.

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