Clay Mineral Distribution in Surface Sediments of the Laptev Sea:
Indicator for Sediment Provinces, Dynamics and Sources
B.T. Rossakl, H. Kassens 2 , H. Lange 2 and J. Thiede 2
(I) Geologisches Landesamt Nordrhein- Westfalen. De-Greiff-Str. 195. D 47803 Krefeld. Germany
(2) GEOMAR Forschungszentrum fur marine Geowissenschaften. Wischhofstrasse 1-3. D 24148 Kiel.
Germanv
Received 1 1 March 1997 and accepted in revised form 1 December 1997
Abstract - Forty-eight surface sediment samples from the Laptev Sea taken during the
Russian - German expedition Transdrift I in summer 1993 were analysed for their clay
mineral composition (illite. smectite. chlorite. and kaolinite). Different clay mineral
provinces. the role of fluvial sediment-supply. transport mechanisms, and possible source
areas are discussed.
The distribution patterns of the clay minerals allow to distinguish between three different
provinces: 1. In the western Laptev Sea sediments are particularly rich in smectite and are
characterized by a slight enrichment in kaolinite. 2. Sediments in the eastern Laptev Sea are
very poor in kaolinite. 3. The southeastern Laptev Sea is dominated by illite and chlorite.
The distribution of clay minerals in the Laptev Sea is controlled both by river run-off and
summer surface currents. The Lena and Yana rivers mainly deliver illite and chlorite,
smectite is supplied almost exclusively by the Anabar and Khatanga rivers, kaolinite by the
Anabar, Khatanga, and Olenek rivers. From the river mouths, surface currents transport
smectite and kaolinite hundreds of km eastward.
mite and chlorite are most probably erosional products of Paleozoic slates cropping out in
the drainage areas of the Lena and Yana rivers. Smectite originates from Mesozoic and
Cenozoic weathering residues of the Permo- Triassic Putoran-Plateau flood basalts.
Kaolinite is probably derived from the erosion of kaolinite-rich Mesozoic sediments of the
Siberian Platform.
Introduction
Recent studies have shown that huge amounts of the sediment-laden sea ice in the Transpolar
Drift (Figure I) are formed over the shallow Siberian shelf areas (Colony and Thorndike, 1984;
Pfirman et a!., 1990). In particular, the smectite concentrations of sea ice sediment samples
taken between 81 ° Nand 83° N are in good correspondence with those in hitherto existing
surface sediment samples of the Laptev Sea suggesting the Laptev Sea as one of the main
sources for sea ice sediments transported by the Transpolar Drift (Silverberg, 1972;
Wollenburg, 1993; Niirnberg et aI., 1994).
This study presents detailed clay mineral distribution patterns of the Laptev Sea. It discusses
different clay mineral provinces, the role of bathymetry, fluvial sediment supply, and transport
mechanisms of the clay minerals. In addition, possible clay mineral source areas in the Siberian
hinterland are shown.
Sedimentary environment and bathymetry of the Laptev Sea
Strongly different winter and summer ice conditions influence the sedimentary environment of
the very broad and shallow Laptev Sea shelf, which has maximum water depths of 50 - 60 m at
its edge. From October to mid-July the Laptev Sea is covered with ice. About 1.5 - 2 m thick
fast ice builds up between shallow coastal areas and the 20 - 30 m isobath (Dethleff et a\.,
1993). An approximately 1800 km long and up to 100 km wide zone of open water (polynya)
separates the fast ice from the northward drift ice zone (Zakharov, 1966; Barnett, 1991;
In: Kassens. H., H.A. Bauch. I. Dmitrenko. H. Eicken. H.-W. Hubberten. M. Melles. l. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag. Berlin, 1999.587-599.
Indicator for Sediment Provinces, Dynamics and Sources
B.T. Rossakl, H. Kassens 2 , H. Lange 2 and J. Thiede 2
(I) Geologisches Landesamt Nordrhein- Westfalen. De-Greiff-Str. 195. D 47803 Krefeld. Germany
(2) GEOMAR Forschungszentrum fur marine Geowissenschaften. Wischhofstrasse 1-3. D 24148 Kiel.
Germanv
Received 1 1 March 1997 and accepted in revised form 1 December 1997
Abstract - Forty-eight surface sediment samples from the Laptev Sea taken during the
Russian - German expedition Transdrift I in summer 1993 were analysed for their clay
mineral composition (illite. smectite. chlorite. and kaolinite). Different clay mineral
provinces. the role of fluvial sediment-supply. transport mechanisms, and possible source
areas are discussed.
The distribution patterns of the clay minerals allow to distinguish between three different
provinces: 1. In the western Laptev Sea sediments are particularly rich in smectite and are
characterized by a slight enrichment in kaolinite. 2. Sediments in the eastern Laptev Sea are
very poor in kaolinite. 3. The southeastern Laptev Sea is dominated by illite and chlorite.
The distribution of clay minerals in the Laptev Sea is controlled both by river run-off and
summer surface currents. The Lena and Yana rivers mainly deliver illite and chlorite,
smectite is supplied almost exclusively by the Anabar and Khatanga rivers, kaolinite by the
Anabar, Khatanga, and Olenek rivers. From the river mouths, surface currents transport
smectite and kaolinite hundreds of km eastward.
mite and chlorite are most probably erosional products of Paleozoic slates cropping out in
the drainage areas of the Lena and Yana rivers. Smectite originates from Mesozoic and
Cenozoic weathering residues of the Permo- Triassic Putoran-Plateau flood basalts.
Kaolinite is probably derived from the erosion of kaolinite-rich Mesozoic sediments of the
Siberian Platform.
Introduction
Recent studies have shown that huge amounts of the sediment-laden sea ice in the Transpolar
Drift (Figure I) are formed over the shallow Siberian shelf areas (Colony and Thorndike, 1984;
Pfirman et a!., 1990). In particular, the smectite concentrations of sea ice sediment samples
taken between 81 ° Nand 83° N are in good correspondence with those in hitherto existing
surface sediment samples of the Laptev Sea suggesting the Laptev Sea as one of the main
sources for sea ice sediments transported by the Transpolar Drift (Silverberg, 1972;
Wollenburg, 1993; Niirnberg et aI., 1994).
This study presents detailed clay mineral distribution patterns of the Laptev Sea. It discusses
different clay mineral provinces, the role of bathymetry, fluvial sediment supply, and transport
mechanisms of the clay minerals. In addition, possible clay mineral source areas in the Siberian
hinterland are shown.
Sedimentary environment and bathymetry of the Laptev Sea
Strongly different winter and summer ice conditions influence the sedimentary environment of
the very broad and shallow Laptev Sea shelf, which has maximum water depths of 50 - 60 m at
its edge. From October to mid-July the Laptev Sea is covered with ice. About 1.5 - 2 m thick
fast ice builds up between shallow coastal areas and the 20 - 30 m isobath (Dethleff et a\.,
1993). An approximately 1800 km long and up to 100 km wide zone of open water (polynya)
separates the fast ice from the northward drift ice zone (Zakharov, 1966; Barnett, 1991;
In: Kassens. H., H.A. Bauch. I. Dmitrenko. H. Eicken. H.-W. Hubberten. M. Melles. l. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag. Berlin, 1999.587-599.