Holocene Prehistory of the Northwestern Subarctic

Author(s):  
Ben Potter

This chapter synthesizes our current understanding of Holocene prehistory (from 11,500 years ago) of the northwest Subarctic, encompassing Alaska, Yukon Territory, and northern British Columbia. Various cultural chronologies are considered, as are new interpretations based on recently excavated sites. These data indicate conservation of lithic technologies concurrent with economic change throughout the region. Periods of cultural transitions occurred at 6,000 and 1,000 years ago. High residential mobility is inferred for most of the Holocene, with radical shifts in settlement and technology throughout the region at 1,000 years ago, though there are elements of continuity. Current debates on ethnogenesis of Athapaskans and the utility of typological approaches are also discussed.

2017 ◽  
Vol 54 (11) ◽  
pp. 1153-1164 ◽  
Author(s):  
B.H. Luckman ◽  
M.H. Masiokas ◽  
K. Nicolussi

As glaciers in the Canadian Rockies recede, glacier forefields continue to yield subfossil wood from sites overridden by these glaciers during the Holocene. Robson Glacier in British Columbia formerly extended below tree line, and recession over the last century has progressively revealed a number of buried forest sites that are providing one of the more complete records of glacier history in the Canadian Rockies during the latter half of the Holocene. The glacier was advancing ca. 5.5 km upvalley of the Little Ice Age terminus ca. 5.26 cal ka BP, at sites ca. 2 km upvalley ca. 4.02 cal ka BP and ca. 3.55 cal ka BP, and 0.5–1 km upvalley between 1140 and 1350 A.D. There is also limited evidence based on detrital wood of an additional period of glacier advance ca. 3.24 cal ka BP. This record is more similar to glacier histories further west in British Columbia than elsewhere in the Rockies and provides the first evidence for a post-Hypsithermal glacier advance at ca. 5.26 cal ka BP in the Rockies. The utilization of the wiggle-matching approach using multiple 14C dates from sample locations determined by dendrochronological analyses enabled the recognition of 14C outliers and an increase in the precision and accuracy of the dating of glacier advances.


1988 ◽  
Vol 10 ◽  
pp. 57-62 ◽  
Author(s):  
G. Holdsworth ◽  
H.R. Krouse ◽  
E. Peake

An historical record of the deposition of common acids is contained in snow and ice cores taken from suitable sites in the accumulation zone of certain glaciers. Spatial and time-series data sets for trace-mineral acids have been obtained from snow-pit samples and ice cores from a number of mountain sites in Alberta, British Columbia, and the Northwest and Yukon Territories. In Alberta, it is possible to use temperate firn sites above 3460 m, although elution occurs during certain summers as indicated by isotopic and ionic data. This would also apply to sites of a similar latitude (52°±2°N) in British Columbia. In the Yukon Territory (≥60.5°N) reliable time series for the acid anions may be obtained from sites at altitudes above 3000 m. Elution provides a natural control for demonstrating that field sampling and subsequent analytical procedures do not introduce significant contamination. The Yukon data are compared with the net annual accumulation rate and with altitude. Recent data from the 5340 m Mt Logan site do not indicate any significant increase in natural background levels of snow acidity. Lightning, which is responsible for numerous forest fires in all provinces, is a possible natural source of nitric acid. Spring-summer peaks in nitrate concentration usually occur. In addition, forest-fire smoke may be a significant contributor to the mountain snow-pack chemistry in some years and must be considered when interpreting the Mt Logan core data. One Yukon profile seems to contain the signature from the 1986 Augustine volcanic eruption.


CJEM ◽  
2019 ◽  
Vol 22 (3) ◽  
pp. 338-341
Author(s):  
Anna Sedlakova ◽  
Paul Olszynski ◽  
Philip Davis ◽  
John Froh

ABSTRACTObjectivesEvidence suggests that prehospital point of care ultrasound (POCUS) may change patient management. It serves as an aid in triage, physical examination, diagnosis, and patient disposition. The rate of adoption of POCUS among aeromedical services throughout Canada is unknown. The objective of this study was to describe current POCUS use among Canadian aeromedical services providers.MethodsThis is a cross-sectional observational study. A survey was emailed to directors of government-funded aeromedical services bases in Canada. Data were analyzed using descriptive statistics.ResultsThe response rate was 82.3% (14/17 aeromedical services directors), representing 41 of 46 individual bases. POCUS is used by aeromedical services in British Columbia, Alberta, Saskatchewan, and Manitoba. New Brunswick, Nova Scotia, Prince Edward Island, and Yukon reported they are planning to introduce POCUS within the next year. Ontario and Newfoundland reported they are not using POCUS and are not planning to introduce it. British Columbia is the only province currently using POCUS on fixed-wing aircraft. Most commonly reported frequency of POCUS use on missions was <25%. Most useful applications are assessment for pneumothorax, abdominal free fluid, and cardiac standstill. The most common barrier to POCUS use is cost of training and maintenance of competence.ConclusionsPrehospital POCUS is available in Western Canada with one third of the Canadian population having access to aeromedical services using ultrasound. The Maritimes and the Yukon Territory will further extend POCUS use on fixed-wing aircraft. While there are barriers to POCUS use, those bases that have adopted POCUS consider it valuable.


1998 ◽  
Vol 130 (4) ◽  
pp. 491-507 ◽  
Author(s):  
K.G.A. Hamilton

AbstractChlorita nearctica is described from the Yukon Territory and is the first member of its genus found in the New World. A synopsis is presented to the Old World species of Chlorita Fieber, 1866 (Typhlocybinae, tribe Empoascini). A new typhlocybine tribe Forcipatini is created for Forcipata DeLong & Caldwell, 1936 and Notus Fieber, 1866. A synopsis of the genus Notus is presented, with Curta as a subgenus containing only the type species. Notus isolatus sp.nov. is described from Drummond Island, Michigan, in Lake Huron and from Quebec. A synopsis of the genus Forcipata DeLong & Caldwell is presented; all species belong to a single subgenus. Five new species are described: F. forficula from Florida, F. ips from Alaska and Yukon, F. montana from the mountains of British Columbia and Montana, and F. unica and F. xlix from Wisconsin. The New World species of the forcipatine genera are keyed.


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