Marine Pleistocene Deposits of the Taymyr Peninsula and their
Age from ESR Dating
D. Bolshiyanoyl and A. Molodkoy2
(1) State Research Center - Arctic and Antarctic Research Institute, 38 Bering St., 199226 St. Petersburg,
Russia
(2) Institute of Geology of the Academy of Sciences of Estonia, 7 Boulevard Estonia, Tallinn, Estonia
Received 3 March 1997 and accepted in revised form 3 March 1998
Abstract - Electron spin resonance (ESR) dating and lithostratigraphic studies of marine
deposits on the TaymyrTaimyr Peninsula suggest that a marine sedimentary environment
dominated during isotope Stages 4, 5, 7, 8, 9 and 15. The marine basins were
predominantly cold and influenced by freshwater.
Introduction
Marine Quaternary deposits are widespread on the Taymyr Peninsula but not well exposed due
to active slope processes. It is thus important that studies of natural outcrops of Quaternary
deposits are combined with information from bore-holes.
Based on the results of drilling carried out by the Central Arctic Geological Exploration
Expedition (Norilsk) and the Polar Geological Exploration Expedition (Khatanga), a general
understanding of the structure of the TaymyrTaimyr Pleistocene sediments has been gained. It
has also been possible to retrieve samples for dating purposes from several of these bore-holes.
This paper summarizes preliminary results of studies of marine deposits on the Taymyr
Peninsula. These studies were carried out during the four field seasons (1993-1996) of the joint
Russian-German expedition "Taymyr-Severnaya Zemlya" and in previous expeditions to the
western part of Taymyr (1986), to northern Taymyr (1988) and to the south-eastern part of the
peninsula (1989-1990).
ESR dating methods
The electron spin resonance method (ESR) was used to date marine mollusc shells, found in
investigated exposures and cores. This is an efficient tool for determining the age of
exoskeleton remnants of malaco-fauna within a time interval of several hundred years to about 1
million years (Molodkov, 1989, 1992, 1993). The dating of subfossil mollusc shells with ESR
is based on the ability of the mollusc shell material to accumulate the absorbed dose of natural
radiation and preserve it over a long period of time (Ikeya and Ohmura, 1981). An estimate of
the paleodose, accumulated during shell burial in embedding deposits, is performed by
comparing the natural intensity of the shell signal in the ESR-spectrum (caused by paramagnetic
carbonate centers) with the intensity of radioactive irradiation induced by a laboratory source.
The radiation background consists of three components: (1) radiation from natural radionuc1ides
scattered in the embedding deposits, with the main contribution to the exposure dose of shells
made by 238U, 232Th, 40K and the decay products of uranium and thorium (88%, on average,
of the total dose); (2) radiation from the uranium and products of its decay incorporated in the
crystalline matrix of the shell carbonate material (= 7%); and (3) cosmic radiation (= 5%). The
radiation dose absorbed by the mollusc shell material is proportional to the concentration of
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. MeIles, 1. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999,469-475.
Age from ESR Dating
D. Bolshiyanoyl and A. Molodkoy2
(1) State Research Center - Arctic and Antarctic Research Institute, 38 Bering St., 199226 St. Petersburg,
Russia
(2) Institute of Geology of the Academy of Sciences of Estonia, 7 Boulevard Estonia, Tallinn, Estonia
Received 3 March 1997 and accepted in revised form 3 March 1998
Abstract - Electron spin resonance (ESR) dating and lithostratigraphic studies of marine
deposits on the TaymyrTaimyr Peninsula suggest that a marine sedimentary environment
dominated during isotope Stages 4, 5, 7, 8, 9 and 15. The marine basins were
predominantly cold and influenced by freshwater.
Introduction
Marine Quaternary deposits are widespread on the Taymyr Peninsula but not well exposed due
to active slope processes. It is thus important that studies of natural outcrops of Quaternary
deposits are combined with information from bore-holes.
Based on the results of drilling carried out by the Central Arctic Geological Exploration
Expedition (Norilsk) and the Polar Geological Exploration Expedition (Khatanga), a general
understanding of the structure of the TaymyrTaimyr Pleistocene sediments has been gained. It
has also been possible to retrieve samples for dating purposes from several of these bore-holes.
This paper summarizes preliminary results of studies of marine deposits on the Taymyr
Peninsula. These studies were carried out during the four field seasons (1993-1996) of the joint
Russian-German expedition "Taymyr-Severnaya Zemlya" and in previous expeditions to the
western part of Taymyr (1986), to northern Taymyr (1988) and to the south-eastern part of the
peninsula (1989-1990).
ESR dating methods
The electron spin resonance method (ESR) was used to date marine mollusc shells, found in
investigated exposures and cores. This is an efficient tool for determining the age of
exoskeleton remnants of malaco-fauna within a time interval of several hundred years to about 1
million years (Molodkov, 1989, 1992, 1993). The dating of subfossil mollusc shells with ESR
is based on the ability of the mollusc shell material to accumulate the absorbed dose of natural
radiation and preserve it over a long period of time (Ikeya and Ohmura, 1981). An estimate of
the paleodose, accumulated during shell burial in embedding deposits, is performed by
comparing the natural intensity of the shell signal in the ESR-spectrum (caused by paramagnetic
carbonate centers) with the intensity of radioactive irradiation induced by a laboratory source.
The radiation background consists of three components: (1) radiation from natural radionuc1ides
scattered in the embedding deposits, with the main contribution to the exposure dose of shells
made by 238U, 232Th, 40K and the decay products of uranium and thorium (88%, on average,
of the total dose); (2) radiation from the uranium and products of its decay incorporated in the
crystalline matrix of the shell carbonate material (= 7%); and (3) cosmic radiation (= 5%). The
radiation dose absorbed by the mollusc shell material is proportional to the concentration of
In: Kassens, H., H.A. Bauch, I. Dmitrenko, H. Eicken, H.-W. Hubberten, M. MeIles, 1. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin, 1999,469-475.