594
Land-Ocean Systems in the Siberian Arctic: Dynamics and History
Anabar and Khatanga rivers. Kaolinite which cannot form under a polar climate is most
probably supplied by the Anabar, Khatanga, and Olenek rivers.
105' E
11 0"
115
120"
125
130
135
140"
78 N
Smecti te [%]
<5
' Stations 01 \he expedition
5-<15
TRANSDRIFT 1.1993
n '
77"
76'
75
75'
74
73
73"
S
72' I
72"
I
I
I
71 N ~
•
I
105' E
110"
115'
120"
125'
140"
145' E
Figure 5: Distribution of smectite in surface sediments of the Laptev Sea.
Obviously, surface currents (Suslov, 1961) play an important role for the spatial distribution
of the flaky clay minerals: eastward surface currents prevent westward transport of illite and
chlorite, whereas kaolinite and in particular the small sized smectite cystals are transported in
suspension hundreds of km to the east (Figure 8).
To explain the enrichment of illite and chlorite in the southeastern part of the Laptev Sea,
bathymetry has to be considered: the southeastern part of the Laptev Sea is limited northward
by the Vasilevsky Bank (Figure 2). The northern end of the brackish surface plume covering
the southeastern Laptev Sea every summer is also located above this shoal (Letolle et aI.,
1993). Probably, the dominant clay minerals of the southeastern Laptev Sea, illite and chlorite,
are settled out of a nepheloid layer described by Utolle et al. (1993) and Burenkov (1993) who
observed this layer in close connection with the brackish surface plume in this area. The good
correspondence of the clay mineral provinces and the benthic faunal zonation (Sirenko and
Piepenburg, 1994) emphasises the combined supply of oxygen, nutrients, and sediment by the
Yana and Lena rivers into the southeastern Laptev Sea.
Ice transport and aeolian input of clay minerals within the Laptev Sea shelf is not obvious
from the clay mineral distribution patterns but cannot be excluded. After Pfirman et al. (1989,
1990) and Wollenburg (1993) aeolian transport of sediments into Arctic sea ice is generally
negligible because of little fallout rates.
Land-Ocean Systems in the Siberian Arctic: Dynamics and History
Anabar and Khatanga rivers. Kaolinite which cannot form under a polar climate is most
probably supplied by the Anabar, Khatanga, and Olenek rivers.
105' E
11 0"
115
120"
125
130
135
140"
78 N
Smecti te [%]
<5
' Stations 01 \he expedition
5-<15
TRANSDRIFT 1.1993
n '
77"
76'
75
75'
74
73
73"
S
72' I
72"
I
I
I
71 N ~
•
I
105' E
110"
115'
120"
125'
140"
145' E
Figure 5: Distribution of smectite in surface sediments of the Laptev Sea.
Obviously, surface currents (Suslov, 1961) play an important role for the spatial distribution
of the flaky clay minerals: eastward surface currents prevent westward transport of illite and
chlorite, whereas kaolinite and in particular the small sized smectite cystals are transported in
suspension hundreds of km to the east (Figure 8).
To explain the enrichment of illite and chlorite in the southeastern part of the Laptev Sea,
bathymetry has to be considered: the southeastern part of the Laptev Sea is limited northward
by the Vasilevsky Bank (Figure 2). The northern end of the brackish surface plume covering
the southeastern Laptev Sea every summer is also located above this shoal (Letolle et aI.,
1993). Probably, the dominant clay minerals of the southeastern Laptev Sea, illite and chlorite,
are settled out of a nepheloid layer described by Utolle et al. (1993) and Burenkov (1993) who
observed this layer in close connection with the brackish surface plume in this area. The good
correspondence of the clay mineral provinces and the benthic faunal zonation (Sirenko and
Piepenburg, 1994) emphasises the combined supply of oxygen, nutrients, and sediment by the
Yana and Lena rivers into the southeastern Laptev Sea.
Ice transport and aeolian input of clay minerals within the Laptev Sea shelf is not obvious
from the clay mineral distribution patterns but cannot be excluded. After Pfirman et al. (1989,
1990) and Wollenburg (1993) aeolian transport of sediments into Arctic sea ice is generally
negligible because of little fallout rates.