Lead-210 Dating and Heavy Metal Concentration in Recent
Sediments of Lama Lake (Norilsk Area, Siberia)
B. Hagedornl, S. Harwart l , M.M.R. van der Loeff2 and M. Melles l
(1) Alfred- Wegener-Institutfur Polar- und Meeresforschung, Forschungsstelle Potsdam, Telegrafenberg A43,
D 14473 Potsdam, Germany
(2) Alfred-Wegener-Institutfur Polar- und Meere~forschung, Postfach 120161, D 27570 Bremerhaven,
Germany
Revised 5 May 1997 and accepted in revised form 15 March 1998
Abstract - Lama Lake is situated in the Noril'sk district of the southern Taymyr
Peninsula, Siberia (69°N, 88°E) and covers an area of 466 km 2 The geology of the
catchment is dominated by Permo-Triassic Continental Flood Basalts (CFB). Cu-Ni
sulfides have been mined in the Noril'sk area since 1930. Radiochemical 210Pb and
geochemical investigations were carried out on a 0.52 m core from Lama Lake. A mean
accumulation rate of 0.04 g cm- 2 a-I was calculated from the 210Pb data. The chemical
composition of the lake sediments identifies the CFB formations as the main source of the
sediment. The Cd, Cu, Pb, Ni and Zn concentrations show a progressive increase from 4
cm depth up to the sediment-water interface. With the identification of the geogenic source
of the sediments, enrichment factors (EFM) of the heavy metals can be calculated as: EFcd
(2.5) > EFpb (2.0) > EFzn (1.3) = EFCu (1.3) = EFNi (1.3). The Cd, Pb and Zn enrichment
factors display the same pattern as those determined in other arctic regions (e.g. Greenland),
whereas Cu and Ni are more enriched in Lama Lake. According to the 210Pb ages, the onset
of heavy metal enrichment took place in 1940, coinciding with the start of mining of CuNi sulfide deposits in the Noril'sk area. This supports the assumption of an anthropogenic
source for the enriched heavy metals in the sediment core.
Introduction
Lake sediments generally provide suitable archives to study paleoecological and climatic
developments of the past, due to a generally continuous history of accumulation, good
preservation and high temporal resolution. 2l0Pb dating has proven a powerful tool for
estimating recent (150 y) sediment accumulation rates, and provides a temporal framework for
the environmental history of a lake and its catchment (Koide et aI., 1973; Krishnaswami et aI.,
1971).210Pb is a product of the natural 238U decay series. Among the other products, 222Rn
(T1f2=3.8 d) appears, partly escapes to the atmosphere and rapidly decays to 210Pb (TII2=22.1
a). The 21 0Pb is scavenged by aerosols, washed out by rain or snow and deposited in the lake
and its catchment. The supply of atmospheric 210Pb to lake sediment depends on several
factors: 1) atmospheric flux, 2) residence time in catchment soils, 3) lake water residence time,
4) particle settling velocity, 5) fraction of metals bound to particulates, and 6) the extent of
sediment focusing in the lake (Appleby and Oldfield, 1992). During the last few years, there
have been a number of field-based studies of stable lead and 210Pb cycling in lakes (e.g. White
and Driscol, 1985). These studies demonstrate the varied and complex dynamic behavior of
lead nuclides. Benoit and Hemond (1991) observed 210Pb mobility under anoxic conditions
and indicated the risk of overestimating 210Pb ages from geochemically lowered, apparent
accumulation rates. On the other hand, Appleby et al. (1979) and Crusius and Anderson (1995)
investigated laminated lake sediments to evaluate the mobility of 210Pb in lake sediments. They
found a good agreement between varve counting and 210Pb dating.
In the past 30 years, 21 0Pb dating, together with heavy metal investigations of lake
sediments, has been used to evaluate the temporal and spatial distribution of anthropogenic
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, 1. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999, 361-376.
Sediments of Lama Lake (Norilsk Area, Siberia)
B. Hagedornl, S. Harwart l , M.M.R. van der Loeff2 and M. Melles l
(1) Alfred- Wegener-Institutfur Polar- und Meeresforschung, Forschungsstelle Potsdam, Telegrafenberg A43,
D 14473 Potsdam, Germany
(2) Alfred-Wegener-Institutfur Polar- und Meere~forschung, Postfach 120161, D 27570 Bremerhaven,
Germany
Revised 5 May 1997 and accepted in revised form 15 March 1998
Abstract - Lama Lake is situated in the Noril'sk district of the southern Taymyr
Peninsula, Siberia (69°N, 88°E) and covers an area of 466 km 2 The geology of the
catchment is dominated by Permo-Triassic Continental Flood Basalts (CFB). Cu-Ni
sulfides have been mined in the Noril'sk area since 1930. Radiochemical 210Pb and
geochemical investigations were carried out on a 0.52 m core from Lama Lake. A mean
accumulation rate of 0.04 g cm- 2 a-I was calculated from the 210Pb data. The chemical
composition of the lake sediments identifies the CFB formations as the main source of the
sediment. The Cd, Cu, Pb, Ni and Zn concentrations show a progressive increase from 4
cm depth up to the sediment-water interface. With the identification of the geogenic source
of the sediments, enrichment factors (EFM) of the heavy metals can be calculated as: EFcd
(2.5) > EFpb (2.0) > EFzn (1.3) = EFCu (1.3) = EFNi (1.3). The Cd, Pb and Zn enrichment
factors display the same pattern as those determined in other arctic regions (e.g. Greenland),
whereas Cu and Ni are more enriched in Lama Lake. According to the 210Pb ages, the onset
of heavy metal enrichment took place in 1940, coinciding with the start of mining of CuNi sulfide deposits in the Noril'sk area. This supports the assumption of an anthropogenic
source for the enriched heavy metals in the sediment core.
Introduction
Lake sediments generally provide suitable archives to study paleoecological and climatic
developments of the past, due to a generally continuous history of accumulation, good
preservation and high temporal resolution. 2l0Pb dating has proven a powerful tool for
estimating recent (150 y) sediment accumulation rates, and provides a temporal framework for
the environmental history of a lake and its catchment (Koide et aI., 1973; Krishnaswami et aI.,
1971).210Pb is a product of the natural 238U decay series. Among the other products, 222Rn
(T1f2=3.8 d) appears, partly escapes to the atmosphere and rapidly decays to 210Pb (TII2=22.1
a). The 21 0Pb is scavenged by aerosols, washed out by rain or snow and deposited in the lake
and its catchment. The supply of atmospheric 210Pb to lake sediment depends on several
factors: 1) atmospheric flux, 2) residence time in catchment soils, 3) lake water residence time,
4) particle settling velocity, 5) fraction of metals bound to particulates, and 6) the extent of
sediment focusing in the lake (Appleby and Oldfield, 1992). During the last few years, there
have been a number of field-based studies of stable lead and 210Pb cycling in lakes (e.g. White
and Driscol, 1985). These studies demonstrate the varied and complex dynamic behavior of
lead nuclides. Benoit and Hemond (1991) observed 210Pb mobility under anoxic conditions
and indicated the risk of overestimating 210Pb ages from geochemically lowered, apparent
accumulation rates. On the other hand, Appleby et al. (1979) and Crusius and Anderson (1995)
investigated laminated lake sediments to evaluate the mobility of 210Pb in lake sediments. They
found a good agreement between varve counting and 210Pb dating.
In the past 30 years, 21 0Pb dating, together with heavy metal investigations of lake
sediments, has been used to evaluate the temporal and spatial distribution of anthropogenic
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, 1. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999, 361-376.