UNIVERSITE TOULOUSE III - PAUL SABATIER Ecole ... - LEGOS

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3.2. Denmark Strait
The section located at the Denmark Strait sill comprises three stations (West, Center and
East). Nd IC profiles are shown in Fig. 2, data are reported in Table 1. Four unfiltered samples
were collected in the DSOW flowing just above the sill: Two samples at station West (479
and 442 m), one sample at station Center (610 m) and one sample at station East (523 m). In
contrast to the homogeneity of its precursors in the EGC, DSOW display heterogeneous Nd
ICs, ranging between –10.3 and –7.5, with an average value of -8.7 ± 1.4. Nd concentrations
are also heterogeneous, ranging between 2.5 and 4.1 ppt, with an average value of 3.2 ± 0.7
ppt. The scatter in these data is mostly due to resuspensions (see sections 3.3 and 3.4). The
mean values are identical to those reported for one sample taken in 1981 downstream of the
Denmark Strait (ε Nd = -8.6 ± 0.5, [Nd] = 3 ppt; Piepgras and Wasserburg, 1987).
Figure 2.
ε Nd profiles in the Denmark Strait and the Nansen Fjord. Note the subsurface minimum,
associated with the Atlantic Water (AW), found at all stations except station West. The dotted
ellipse shows the DSOW samples. Note the scattering of the DSOW data and their rather
radiogenic values. The unbroken ellipse shows the "pure DSOW" (not subject to unradiogenic
particle resuspension). The filled circle represents the filtered bottom sample from station
Center.
Nd ICs and concentrations differ greatly from those found in the EGC. Two hypotheses
can explain this difference. Either the waters sampled in the EGC underwent Nd inputs
between 70°N and the Denmark Strait, or they mixed with waters coming from the Iceland
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