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Table 1. The 14 C-AMS Dates in Cores Hu97048-09, Hu97048-16, and Hu98039-05
Uncorrected 14 C
Age (years) ±1 σ Error
Calendar Year B.P. a
(1 σ Age Range)
Reference b
Subsample
Depth (cm)
Hu97048-09
1
135
-
136
10,710 ± 35
11,934
-
12,065
this study
2
240
-
242
11,569 ± 75
12,948
-
13,089
1
3
255
-
257
11,440 ± 160
12,841
-
13,069
1
4
380
-
382
12,770 ± 40
14,082
-
14,274
this study
5
435
-
437
13,130 ± 40
14,864
-
15,095
this study
6
460
-
462
14,870 ± 160
17,007
-
17,666
1
7
495
-
497
13,600 ± 110
15,323
-
15,755
1
8
865
-
867
14,620 ± 40
16,705
-
17,092
this study
9
875
-
877
15,500 ± 75
18,137
-
18,361
1
10
1100
-
1102
20,400 ± 140
23,711
-
24,095
1
Hu97048-16
1
175
-
176
9,100 ± 40
9,673
-
9,844
this study
2
300
-
302
10,150 ± 35
11,106
-
11,164
this study
3
460
-
462
11,830 ± 30
13,212
-
13,277
this study
4
470
-
472
14,620 ± 170
16,592
-
17,233
1
5
558
-
559
14,900 ± 130
17,080
-
17,672
1
6
559
-
561
14,990 ± 45
17,338
-
17,755
this study
7
750
-
752
20,990 ± 200
24,276
-
24,924
1
8
840
-
842
21,200 ± 110
24,833
-
25,322
1
9
858
-
859
21,660 ± 245
25,501
-
25,778
1
10
900
-
902
22,800 ± 110
26,906
-
27,172
1
Hu98039-05
1
169
-
172 (strong leach)
9,210 ± 25
9,888
-
10,037
this study
2
169
-
172
9,240 ± 25
9,949
-
10,093
this study
3
249
-
254
10,070 ± 120
10,868
-
11,148
this study
13,746 this study
a All 14 C-AMS dates were determined on Neogloboquadrina pachyderma (sinistral) (Nps), which were converted to calendar age (B.P.)
by using Calib 6.0.1 [Reimer et al., 2009] calibration program (see text).
b Reference 1 is Rashid et al. [2003a].
4
369
-
374
12,180 ± 170
13,407
-
samples, CO 2 was extracted at 90°C with an ISOCARB TM
device online with a VG-PRISM TM mass spectrometer
(Center for Research in Isotopic Geochemistry and Geo-
chronology, Université du Québec à Montréal) using a
marble standard calibrated against the Carrara marble and
other current standard materials of the International Atomic
Energy Agency. Results were corrected and converted to the
Vienna Peedee belemnite scale. The overall analytical re-
producibility, as determined from replicate measurements
on the standard material, is routinely better than ±0.04
Spectrometry Facility at Woods Hole Oceanographic Insti-
tution, IsoTrace Laboratory of University of Toronto, Na-
tional Science Foundation Accelerator Mass Spectrometry
Facility at University of Arizona, and Keck Carbon Cycle
Laboratory of University of California at Irvine). The 14 C-
AMS dates were converted to calendar years B.P. (1950)
using the CALIB6.0.1 online software program [Reimer et
al., 2009] where MARINE09 data sets were used. We have
adopted the age with the highest probability, and the cali-
brated ages are reported as
(see Table 1). We assigned a
regional reservoir age correction (
ka
18 O, respectively.
Accelerator mass spectrometric radiocarbon ( 14 C-AMS)
dates were used to constrain the stratigraphy of all cores.
These dates were obtained using 800
13 C and
(±1
σ
) and ±0.08
(±1
σ
) for
δ
δ
R) of 50 years [Reimer et
al., 2009] to account for the apparent age of dissolved inor-
ganic carbon in high-latitude sea surface waters of the north-
west Labrador Sea not accounted for in the MARINE09 data
set [Reimer et al., 2009]. This
Δ
1200 handpicked tests/
sample of N. pachyderma (s). All ages reported here were
calculated after isotopic normalization (i.e., for a
-
R may be a minimal estimate
for the early Holocene conditions in the northwest Labrador
Sea. For example, preindustrial
Δ
13 C value
δ
s 14 C half-life as provided by the
laboratories (National Ocean Sciences Accelerator Mass
of
25
) using Libby
'
R for infaunal mollusks in
Hudson Strait and adjacent areas has been estimated as 334 ±
Δ
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