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18
O
in N. pachyderma (s), and (d)
14
C-AMS dates (ka) versus depth (m). It was collected at 1575 m water depth. Lack of
N. pachyderma (s) prevented acquiring of
δ
Figure 3.
Core Hu97-09 from the slope seaward of Hudson Strait showing (a) sediment facies, (b) carbonate (%), (c)
δ
18
O between 5.8 and 8.4 m. Horizontal gray bars represent H0 and H1 [Rashid
et al., 2003a].
show an alternation of thinly laminated IRD and finely
laminated detrital carbonate-rich fine-grained sediments with
occasional dropstones. The upper part of H0 shows a gradual
transition to the overlying hemipelagic sediments. X-ray
diffraction on bulk sediments and petrological identification
of IRD granules in core Hu97-16 demonstrate the dominance
of calcite in H0, as well as in H1 [Rashid et al., 2003a;
Rashid and Piper, 2007]. The
δ
2440 and 2446 m water depths, respectively, Kirby [1998]
identified a H0 bed overlying a well-developed H1 and H2,
based on a slight increase in carbonate and higher calcite/
dolomite ratio (Figures 5e and 5f). In the absence of age
control and a clearer carbonate signature, we regard this
interpretation of H0 as unconfirmed: the uppermost part of
the piston core is commonly disturbed, and the slight car-
bonate signature might be of Holocene age. Because of the
possibility of core top loss, the absence of H0 cannot be
confirmed from these cores. H0 in cores Hu82-57 and
Hu84-08, which was retrieved at 549 and 580 m water depths
from the Resolution Basin, was identified by the high-
carbonate intervals (Figures 5a and 5b). The identification
of H0 in these cores is constrained by six published dates
[Andrews et al., 1995]. On the southeast Baffin Slope, core
Hu97048-07, which was retrieved at 938 m water depth,
contains a 50 cm thick H0 bed identified by radiocarbon
18
OinN. pachyderma (s)
18
O
Nps
) in H0 is 0.5
‰
depleted compared with immedi-
ately underlying sediment but is little different from overly-
ing Holocene sediment (Figures 2 and 3).
Core Hu97-11, which was retrieved seaward of the central
part of the Hatton Basin transverse trough (Figure 4), has no
detectable record of an H0 layer, despite a high-resolution
record in the trigger weight core. Core Hu97-13 also appears
to lack H0 but may have experienced core top loss [Rashid
and Piper, 2007]. In cores Hu7509-55 and Hu7509-56 at
(
δ
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