Determination of Depositional Beryllium-10 Fluxes in the Area of
the Laptev Sea and Beryllium-10 Concentrations in Water Samples
of High Northern Latitudes
c. Strobil, V. Schulz l , S. Vogler l , S. Baumann l , H. Kassens 2 , P.W. Kubik 3 , M. Suter4
and A.Mangini l
(1) Heidelberger Akademie der Wissenschaften, 1m Neuenheimer Feld 366, D 69120 Heidelberg, Germany
(2) GEOMAR Forschungszentrumfurmarine Geowissenschaften, Wischhofstrasse 1-3, D 24148 Kiel,
Germany
(3) Paul Scherrer Institut, c/o Institutfur Partikelphysik. ETH Honggerberg, 8093 Zurich, Switzerland
(4) Institut fur Partikelphysik, ETH Honggerberg, 8093 Zurich, Switzerland
Received 20 February 1997 and accepted in revised form 9 May 1998
Abstract - Present day accumulation rates of nine sediment cores recovered during the
Russian-German Expedition Transdrift II (1994) from the shelf area of the Laptev Sea were
determined by 210Pb ex dating and vary from 0.05 to 0.24 g cm- 2 a-I In addition, the
sedimentation rates during the isotopic stages 2, 3 and 5 of the sediment core PS 2471-4
from the continental slope of the Laptev Sea were determined via 230Thex dating. The lOBe
concentrations together with the accumulation rates (or sedimentation rates) yield the
depositional lOBe fluxes in the shelf area of [(10 - ISO) .10 6 at cm- 2 a-I] and of [(0.9 - 4.1)
.10 6 at cm- 2 a-I] on the continental slope from the Laptev Sea. They are clearly higher than
the recent atmospheric input determined in Greenland ice cores [(0.2 - 0.5) .10 6 at cm-2 aI]. We conclude that large amounts of continental lOBe are delivered to the Laptev Sea
through the rivers (e.g. Lena,Yana) and that the major fraction of lOBe is deposited directly
in the shelf area. The distinctly higher concentrations of lOBe in water samples from the
shelf area of the Laptev Sea [1000 to 6000 at/g] compared to the concentrations measured in
the Norwegian and Greenland Sea [300 to 1000 at/g] and the Central Arctic Ocean [500
at/g] are further evidence that rivers are an important source for the input of lOBe from the
Siberian hinterland to the Arctic Ocean.
Introduction
The cosmogenic radionuc1ide lOBe (tll2 = l.5 Ma) is a sensitive stratigraphic tool for sediments
from the Arctic Ocean with low or negligible content of biogenic carbonate. lOBe records from
sediment cores from the Norwegian and Greenland Sea exhibit high concentrations of lOBe
during the interglacials in contrast to lower values during glacial periods (Eisenhauer et a!.,
1994). These distinct changes enable a glacial/interglacial stratigraphy of Arctic sediments.
Better knowledge of the pathways of lOBe from the Laptev Shelf into the sediments of the
Arctic Ocean could render the records from sediment cores of the Arctic Ocean more reliable.
As part of the Russian-German cooperative research project "System Laptev Sea" we focussed
on the evaluation of supply and export fluxes of lOBe in the shelf area and on the continental
slope of the Laptev Sea. The atmospheric input was measured in ice cores from the Greenland
Ice Sheet (Stanzick, 1996). The supply of lOBe with the river was determined from the
measurement of water samples from the estuary of the river Lena. For comparison we also
measured profiles of the lOBe contentration at three localities in the central Arctic Ocean. The
amount of riverine lOBe deposited on the shelf was evaluated from the concentration of lOBe in
shelf sediments. The accumulation rates of the sediments were determined from profiles of
210Pb ex '
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, J. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999,515-532.
the Laptev Sea and Beryllium-10 Concentrations in Water Samples
of High Northern Latitudes
c. Strobil, V. Schulz l , S. Vogler l , S. Baumann l , H. Kassens 2 , P.W. Kubik 3 , M. Suter4
and A.Mangini l
(1) Heidelberger Akademie der Wissenschaften, 1m Neuenheimer Feld 366, D 69120 Heidelberg, Germany
(2) GEOMAR Forschungszentrumfurmarine Geowissenschaften, Wischhofstrasse 1-3, D 24148 Kiel,
Germany
(3) Paul Scherrer Institut, c/o Institutfur Partikelphysik. ETH Honggerberg, 8093 Zurich, Switzerland
(4) Institut fur Partikelphysik, ETH Honggerberg, 8093 Zurich, Switzerland
Received 20 February 1997 and accepted in revised form 9 May 1998
Abstract - Present day accumulation rates of nine sediment cores recovered during the
Russian-German Expedition Transdrift II (1994) from the shelf area of the Laptev Sea were
determined by 210Pb ex dating and vary from 0.05 to 0.24 g cm- 2 a-I In addition, the
sedimentation rates during the isotopic stages 2, 3 and 5 of the sediment core PS 2471-4
from the continental slope of the Laptev Sea were determined via 230Thex dating. The lOBe
concentrations together with the accumulation rates (or sedimentation rates) yield the
depositional lOBe fluxes in the shelf area of [(10 - ISO) .10 6 at cm- 2 a-I] and of [(0.9 - 4.1)
.10 6 at cm- 2 a-I] on the continental slope from the Laptev Sea. They are clearly higher than
the recent atmospheric input determined in Greenland ice cores [(0.2 - 0.5) .10 6 at cm-2 aI]. We conclude that large amounts of continental lOBe are delivered to the Laptev Sea
through the rivers (e.g. Lena,Yana) and that the major fraction of lOBe is deposited directly
in the shelf area. The distinctly higher concentrations of lOBe in water samples from the
shelf area of the Laptev Sea [1000 to 6000 at/g] compared to the concentrations measured in
the Norwegian and Greenland Sea [300 to 1000 at/g] and the Central Arctic Ocean [500
at/g] are further evidence that rivers are an important source for the input of lOBe from the
Siberian hinterland to the Arctic Ocean.
Introduction
The cosmogenic radionuc1ide lOBe (tll2 = l.5 Ma) is a sensitive stratigraphic tool for sediments
from the Arctic Ocean with low or negligible content of biogenic carbonate. lOBe records from
sediment cores from the Norwegian and Greenland Sea exhibit high concentrations of lOBe
during the interglacials in contrast to lower values during glacial periods (Eisenhauer et a!.,
1994). These distinct changes enable a glacial/interglacial stratigraphy of Arctic sediments.
Better knowledge of the pathways of lOBe from the Laptev Shelf into the sediments of the
Arctic Ocean could render the records from sediment cores of the Arctic Ocean more reliable.
As part of the Russian-German cooperative research project "System Laptev Sea" we focussed
on the evaluation of supply and export fluxes of lOBe in the shelf area and on the continental
slope of the Laptev Sea. The atmospheric input was measured in ice cores from the Greenland
Ice Sheet (Stanzick, 1996). The supply of lOBe with the river was determined from the
measurement of water samples from the estuary of the river Lena. For comparison we also
measured profiles of the lOBe contentration at three localities in the central Arctic Ocean. The
amount of riverine lOBe deposited on the shelf was evaluated from the concentration of lOBe in
shelf sediments. The accumulation rates of the sediments were determined from profiles of
210Pb ex '
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, J. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999,515-532.