Geological Survey of Canada radiocarbon dates XXI

Abstract

This list includes 105 radiocarbon age determinations on 104 geological samples made by the Radiocarbon Dating Laboratory. They are on samples from various are as follows: Labrador Shelf (2); Newfoundland (12); Nova Scotia (2); New Brunswick (1): Quebec (3); Ontario(1); Manitoba(1); Alberta (2); British Columbia (15); Yukon Territory (35); Northwest Territories, Mainland (10); Northwest Territories, Arctic Archipelago (21). Details of background and standard for the 2 L and 5 L counters during the period from November 4, 1980 to October 31, 1981 are summarized in Tables 1 and 2; Table 3 gives the number of counts used to determine the average background and standard counting rates; and Table 4 lists the number of different background and standard gas preparations used for counting.

Late Wisconsinan buildup and wastage of the Innuitian Ice Sheet across southern Ellesmere Island, Nunavut

“…The rate of retreat to this position is unknown because of the current lack of dates from the outer part of the inlet. However, a date of 9.3 ka BP (GSC-3183, Lowdon and Blake 1981) obtained on shells at Clarence Head, 120 km to the east on Smith Sound (Fig. 1), provides a similar, minimum age for marine limit in central Makinson Inlet.…”

Permafrost Distribution in Peatlands of West-Central Canada During the Holocene Warm Period 6000 Years BP

“…There are indications that bog development and associated permafrost formation began earlier in the north and gradually spread southward. Within 1170±150 6510±150 5070±60 6160±90 2800±100 4250±100 6070±100 6280±80 1320±60 7590±80 6940±110 9820±220 2080±60 4750±60 2920±130 6770±140 8260±110 10100±130 1890±60 4810±60 3150±90 6020±100 2200±80 4030±100 2130±80 3850±400 920±80 3890±160 2300±100 Lowdon et ai, 1967Lowdon era/., 1967Tarnocai & Zoltai, 1988Tamocai & Zoltai, 1988Tarnocai & Zoltai, 1988Tarnocai & Zoltai, 1988 This paper This paper Blake, 1987Blake, 1987Dyck & Fyles, 1963Dyck & Fyles, 1963Blake, 1988Blake, 1988Lowdon & Blake, 1981Lowdon & Blake, 1981 This paper This paper Tarnocai & Zoltai, 1988Tarnocai & Zoltai, 1988Tarnocai & Zoltai, 1988Tarnocai & Zoltai, 1988Zoltai et al, 1992Zoltai et al, 1992 This paper This paper This paper This paper This paper This paper Alberta, bog development occurred earlier in the north (about 5 ka) than farther south in the present LPZ (about 2.2 ka, Zoltai and Vitt, 1990). …”

Investigating the glacial history of the northern sector of the Cordilleran Ice Sheet with cosmogenic 10Be concentrations in quartz

“…The McConnell glaciation is firmly dated to OIS 2 (Late Wisconsin). Radiocarbon ages from wood and fossils underlying McConnell till indicate that the McConnell glaciation began after 29,600±300 14 C yr BP (Matthews et al, 1990), but glaciers did not advance into major valleys before 26,350±280 14 C yr BP (Jackson and Harington, 1991), and a fully developed CIS did not exist until after 23,900±1140 14 C yr BP (Lowdon and Blake, 1981). Published radiocarbon ages indicate that the St. Elias lobe of the CIS was in retreat by 13,660±180 14 C yr BP (Rampton, 1971) and the Selwyn lobe by 12,590±120 14 C yr BP (Ward, 1989) (Fig.…”