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years, Labrador and Northeast Newfoundland shelves
144±38 years, and Scotian Shelf 83±14 years.
Recently, an added correction of
flows over the upper slope. It combines cold, low-salinity
water from the southward flowing BafnIslandCurrent
(originating in the Arctic) with warmer more saline waters
from the West Greenland Current moving westward across
Davis Strait. The cold, low-salinity inner branch of the
Labrador Current derives mainly from the Baf
200±10 years was
established for the region using a palynological transfer
function estimate of early Holocene annual sea ice duration
on the central Labrador Shelf (about 11 months versus
5
nIsland
Current and water out of the Hudson Strait and is seasonally
fedbyseaicemelt[Loder et al., 1998]. The Labrador
Current
6 months at present) [Lewis et al., 2009] in conjunction
with a model of annual sea ice duration versus increase in
marine
14
C reservoir age [Bard et al., 1994; Mangerud et al.,
2006]. This correction of
-
flows southward from the Labrador Shelf onto the
Northeast Newfoundland Shelf, and then the greater part
turns east and north along the eastern margin of the Grand
Banks and runs parallel with the NAC before joining it north
of Flemish Cap (Figure 1). A smaller part of the Labrador
Current continues south and west to follow the southern
margin of the Grand Bank, to the Laurentian Fan, and along
the Scotian Shelf margin. There is an out
200 years, when added to the
conventional radiocarbon ages for constraints on the Agassiz
floods and calibrated to calendar years, resulted in an adjusted
age of the
final Lake Agassiz drainage of 8.33 ka (7.5
14
C ka)
with an error range of 8.15
-
8.48 ka [Lewis et al., 2009]. Beds
of elevated DC with bracketing ages that correlate with this
age range (e.g., HU87033-19P: 295
380 cm, this chapter)
are attributed to deposition from iceberg detritus and plumes
of sediment transported from Hudson Bay via the Lake
Agassiz
-
ow of slightly
fresher water from the Gulf of St. Lawrence on the western
side of Cabot Strait [Han et al., 1999].
Water on the Northeast Newfoundland Shelf is character-
ized by low temperatures and low salinity. Over the core site,
the SST in August is between 9°C and 10°C, and sea surface
salinity (SSS) is 32.5
floodwaters in the Labrador Current [Lewis et al.,
2009].
(in psu scale) [Levitus, 1982; Loder
et al., 1998]. The seasonal duration of sea ice cover is
4 months [Markham, 1988]. In winter, the minimum SST is
‰
2. REGIONAL SETTING
2.1. Location of Study Areas
1.5° C, and the SSS is between 33.0
‰
and 33.5
‰
[Loder
et al., 1998].
St. Anne
Notre Dame Channel is an intrashelf basin located on the
Northeast Newfoundland Shelf (Figure 1). Intrashelf basins
and outer shelf banks are common on the eastern Canadian
margin and are probably the result of glacial erosion and
deposition, respectively [Grant and McAlpine, 1990; Piper
et al., 1990]. Notre Dame Channel is oriented approximately
SW-NE and is separated from the Northeast Newfoundland
Slope by a 330 m deep shelf-edge sill. Sediment deposition is
uniform and continuous, without hiatus [Dale and Haworth,
1979; Miller, 1999]. Core HU87033-19 (hereafter referred to
as core 19) was recovered at 50°54.51
′
N and 53° 15.63
′
Wat
a water depth of 453 m [Vilks and Powell, 1987].
St. Anne
is Basin is located near the Laurentian Channel,
which is a major exchange pathway between the Atlantic
Ocean and the Gulf of St. Lawrence waters and also a
con
'
uence zone for continental runoff from the St. Lawrence
River, the Labrador Current, and offshore slope waters
[Loder et al., 1997].
The sea surface conditions over the northeast Scotian Shelf
clearly re
ect the input from the Gulf of St. Lawrence
through Cabot Strait. Salinity is lower along the coast of
Cape Breton and on the inner Scotian Shelf and gradually
increases offshore [Loder et al., 1997; Petrie et al., 1996].
Over St. Anne
'
is Basin, the mean SST is 0°C in February and
16°C in August. SSS is higher in February (31.5
is Basin is located on the northeast part of the
Scotian Shelf, 50 km from the edge of the Laurentian Chan-
nel (Figure 1). The basin has a length of 7 km and a width of
3 km. It lies on the inner shelf, about 40 km south-southeast
of Cape Breton Island. Core HU84011-12 (hereafter referred
to as core 12) was taken near the center of the basin at 45°
46.72
'
) than in
August (30 psu) [Levitus and Boyer, 1994]. The duration of
the sea ice cover is variable around Cape Breton. While the
average duration is 80
‰
100 days on the west side of the
island, it is only 40 days along the southern coast and over
St. Anne
'
s Basin [Drinkwater et al., 1999].
-
N; 58°39.16
W, at a water depth of 270 m.
′
′
2.3. Modern Vegetation Distribution and Associated
Pollen Record
2.2. Oceanographic Conditions of the Area
Water over the Northeast Newfoundland Shelf is heavily
in
ows southeast-
ward and parallel to the Labrador coast (Figure 1). The main
branch of the Labrador Current is less than 100 km wide and
uenced by the Labrador Current, which
2.3.1. Vegetation in Northern Newfoundland. Northern
Newfoundland forests lie within the spruce-fir subdivision
of the boreal forest [Rowe, 1977]. The most abundant tree in
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