Strobl et al.: Determination o{Depositional Bervllium-JO Fluxes in the Area ofthe Laptev Sea
525
1977). Our data suggest an atmospheric flux of 21 0Pb for the area of the Laptev Sea:::; 0,6 dpm
cm-2 a-I, which is in agreement with model results of Rehfeld (1994).
Sedimentary lOBe-Fluxes in the Shelf Area afthe Laptev Sea
The sedimentation rates from Table 3 were used to calculate the deeositional lOBe flux into the
sediments of the shelf area from the Laptev Sea. The depositional I( Be flux is defined as:
F(x) = C(x) • S(x) • p(x)
where:
F: depositional lOBe flux [at cm- 2 a-I]
C: concentration of lOBe [atoms g-I]
S: sedimentation rate [cm ka- 1 ]
p: dry bulk density [g cm- 3 ]
(10)
In Table 6 the lOBe concentrations and the depositional lOBe fluxes of the investigated
sediment cores are listed. These lOBe fluxes of [(10 - 150) .1Q6at cm- 2 a-I] in the shelf area of
the Laptev Sea, are by two orders of magnitude higher than the recent atmospheric input [(0.2 -
0.5) .106 at cm- 2 a-I] in Greenland (Stanzick, 1996) and other world regions (Table 7). This
surplus of lOBe indicates a significant supply of continental lOBe with the rivers into the Laptev
Sea during the last century.
Table 6: Measured lOBe concentrations and the calculated lOBe depositional fluxes.
Station
Depth
lOBe
Depositional lOBe Flux
[em]
[108 atoms g-I)
[106 atoms cm-2 a-I]
PM 9402-3
0- I
2.95 ± 0.23
36.8 ± 8.0
PM 9402-3
14 - 16
3.28 ± 0.16
48.8 ± 10.0
PM 9402-3
32 - 36
3.53 ± 0.14
49.1 ± 10.0
PM 9417-4
0- 1
4.62 ± 0.32
19.9 ± 3.0
PM 9451-7
1 - 2
0.56 ± 0.11
PM 9462-1
0- I
3.53±0.16
26.0 ± 3.0
PM 9462-1
14 - 16
4.49 ± 0.21
40.5 ± 5.0
PM 9463-8
1 - 2
3.93 ± 0.30
72,9 ± 15,0
PM 9463-8
14 - 16
4.02 ± 0.31
I05.6±21.0
PM 9463-8
32 - 36
4.78 ± 0.23
105.4±21.0
PM 9481-2
1 - 2
1.87±0.19
36.2 ± 8.0
PM 9481-2
14 - 16
1.99±0.10
38.9 ± 7.0
PM 9482-1
0- 1
4.10 + 0.44
68.6 + 12.0