Allerød–Younger Dryas Coleoptera from western Cape Breton Island, Nova Scotia, Canada

1996 ◽  
Vol 33 (1) ◽  
pp. 33-41 ◽  
Author(s):  
Randall F. Miller
Keyword(s):  
Nova Scotia ◽  
Younger Dryas ◽  
Late Glacial ◽  
Cold Climate ◽  
Western Cape ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Beetle Assemblages ◽  
Climate Indicator ◽  
Younger Dryas Event

Studies of Coleoptera remains from two late-glacial sites on Cape Breton Island, Nova Scotia, Canada, present a picture of the paleoenvironment and paleoclimate during the Allerød–Younger Dryas transition in the Maritimes region. They provide evidence for the Younger Dryas event in northeastern North America. Between 11 300 and 10 800 BP, the beetle assemblages at the Campbell site are typical of faunas of the modern middle to northern boreal forest. The West Mabou site contains beetle fossils younger than 10 900 BP, possibly as young as 10 500 BP, extending into the time period of the Younger Dryas, dated from 10 800 to 10 000 BP in the Maritimes. A "cold climate" indicator recognizable in the beetle fauna, Olophrum boreale, occurs in relative abundance and provides an interesting comparison with sites in Europe where the same northern boreo-montane species is evident at the beginning of the Younger Dryas.

Late-glacial (Allerød – Younger Dryas) Coleoptera from central Cape Breton Island, Nova Scotia, Canada

1997 ◽  
Vol 34 (3) ◽  
pp. 247-259 ◽  
Author(s):  
Randall F. Miller
Keyword(s):  
Nova Scotia ◽  
Boreal Forest ◽  
Younger Dryas ◽  
Ground Cover ◽  
Late Glacial ◽  
Polar Front ◽  
Climate Data ◽  
Cape Breton Island ◽  
The North ◽  
Cape Breton

Coleoptera from three late-glacial sites on Cape Breton Island, Nova Scotia, Canada, provide proxy climate data from 12 600 to 10 400 BP. Samples older than about 11 800 BP contain tundra to tree-line species. Between 11 800 and about 10 800 BP, beetle assemblages become typical of the modern boreal forest. Beetles younger than 10 800 BP responded to climatic deterioration during the Younger Dryas. Although coleopteran evidence for the Younger Dryas is not as strong as that presented by palynological and stratigraphic studies, the appearance of Olophrum boreale and other species found today in the northern boreal forest and on tundra or coastal tundra corresponds with the decline of shrub birch and the rise in willow and alder pollen. Beetles responded just as likely to changes in vegetation and ground cover as to changes in temperature. The extent to which Coleoptera were affected may lie somewhere between a moderated continental response seen in the Great Lakes region in North America and more extreme changes recorded in Europe. This response is consistent with shifts in the North Atlantic oceanic Polar Front in the Ruddiman and McIntyre model.

Deglaciation of Port Hood Island, Nova Scotia

1974 ◽  
Vol 11 (10) ◽  
pp. 1357-1365 ◽  
Author(s):  
J. Terasmae
Keyword(s):  
Nova Scotia ◽  
Radiocarbon Dating ◽  
Climatic Conditions ◽  
Western Cape ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Soil Creep ◽  
Palynological Study ◽  
Surficial Deposits

A palynological study and radiocarbon dating of surficial deposits on Port Hood Island, Nova Scotia, have indicated that deglaciation occurred more than 11 000 yr B.P., and that the presence of an 'upper till' in local depressions is attributable to soil-creep processes under cold and wet climatic conditions some 11 000 to 10 000 yr B.P. No evidence was found of an ice advance younger than 11 000 yr B.P. in western Cape Breton Island.

Determination of nearshore geologic structure off western Cape Breton Island, Nova Scotia, using high-resolution marine magnetics

2002 ◽  
Vol 39 (9) ◽  
pp. 1299-1312 ◽  
Author(s):  
Sonya A Dehler ◽  
D Patrick Potter
Keyword(s):  
Nova Scotia ◽  
High Resolution ◽  
Transition Zone ◽  
Magnetic Data ◽  
Magnetic Observatory ◽  
Western Cape ◽  
Offshore Structure ◽  
Seismic Reflection Data ◽  
Cape Breton Island ◽  
Cape Breton

New high-resolution magnetic data have been acquired along the coast of western Cape Breton Island near Cheticamp, Nova Scotia, in a transition zone between exposed, elevated basement of the Cape Breton highlands and the adjacent Carboniferous sediment-filled Magdalen Basin. These data were collected to provide continuity between the mapped onshore geology and the geophysical-based interpretations of offshore structure. Separation of the geologic component of the data from the effects of diurnal and other variations in the Earth's magnetic field was made difficult by recording problems at the nearby base recording station. Careful correlation of the fragmented station signal with records from a nearby permanent magnetic observatory enabled a reasonable diurnal signal to be synthesized and applied successfully to the data. Additional processing and filtering helped to enhance small anomalies in the data. Several low-amplitude, fairly linear magnetic anomalies are visible in the reduced anomaly data, generally trending north to northwest away from the coastline. Small-amplitude lineations in the offshore at Cheticamp are associated with folded, tilted, or faulted strata imaged on coincident seismic reflection data and are interpreted as representing juxtaposed units of Carboniferous strata. Other small anomalies appear to represent shallow contacts between intrusive or metasedimentary rocks visible in outcrops near the coast. A stronger, coast-parallel anomaly that extends across the study area from a regional magnetic high in the north is coincident with an offset in basement rocks or deeper strata beneath Carboniferous basin fill. This anomaly may mark part of the faulted transition zone between the elevated highlands of northwestern Cape Breton Island and the Magdalen Basin depocentre.

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