Main Structural Elements of Eastern Russian Arctic Continental
Margin Derived from Satellite Gravity and Multichannel Seismic
Reflection Data
S.S. Drachev l ,2, G.L. Johnson 3 , S.W. Laxon 4 , D.C. McAdoo 5 and H. Kassens 2
(1) P.P. Shirshov Institute of Oceanology, 36 Nakhimovsky Prospekt, I178S1 Moscow, Russia
(2) GEOMAR Forschungszentrumfiir marine Geowissenschaften, Wischhofstrasse 1-3, D 24148 Kiel,
Germany
(3) University of Alaska, Fairbanks, Alaska 9977S-7220, USA
(4) University College London, Space and Climate Physics Department, MSSL, Holmbury St. Mary, Dorking
Surrey, RHS 6NT, UK
(5) NOAA, NODC, LSA, Silver Spring, MD 20910, US
Received I May 1997 and accepted in revised fonn 16 September 1997
Abstract - This paper presents an analysis of the altimeter derived marine gravity data and
available multichannel seismic reflection profiles of the northeastern Siberia continental
margin to provide a preliminary delineation of its geologic structure. Both data sets allow
making a suggestion that the continental margin was strongly affected by the rifting
process since mid of Mesozoic. The main rift zones extend south- and southeastward from
the shelf edge toward the mainland. These are the Laptev Rift System, New Siberian and
ViI 'kitskii rifts in the East Siberian Sea, and North Chukchi rift basin in the Chukchi Sea.
These structures may represent both active and aborted rifts related to extension episodes in
the Arctic Ocean, namely: initial rifting in the Canada Basin (Middle Jurassic to
Hauterivian), opening of the Makarov Basin (53-80 Ma ?) and spreading in the Eurasia
Basin (0-56 Ma). Thus it is suggested that the spreading migrated westward during the
Cretaceous-Cenozoic time and led to separation and fragmentation of the continental blocks
(Lomonosov and Mendeleev ridges, Chukchi Plateau) and subsidence of the rift basins on
the eastern Russian Arctic continental margin.
Introduction
The Arctic Ocean is unique among the oceans of the world in that half of its area is underlain by
continental shelf, primarily the wide European and Siberian continental shelves. The Laptev,
East Siberian and Chukchi seas overlie the extensive shelf of northeaster Russia which is up to
800 km wide and totals about 2,000,000 km 2 in area (Figure 1). To the north, this continental
margin is bordered by the Eurasia and Amerasia oceanic basins which contain large submarine
ridges and plateaus including: the Gakkel, Lomonosov, Alpha-Mendeleev and Chukchi
Borderland.
The structure and tectonic history of the shelf are very poorly known and are primarily a
postulated extension of the terrestrial geology of the New Siberian, De Long and Wrangel
islands and the mainland (Vinogradov et aI., 1977; Vinogradov, 1984; Fujita and Cook, 1990;
Kos 'ko, 1984; Kos 'ko et aI., 1990). Of the three seas, the Laptev Sea is better known as the
result of the Russian seismic reflection studies which have defined the rift basins (Ivanova et
aI., 1990; Drachev et aI., 1995a). The structural pattern and geological history of the remainder
of the continental margin are still largely unknown and there are as many points of view as there
are investigators. Since beginning of the 1970s, the Russian airborne magnetic data were the
primary available means of deciphering the geology of this region (for more detail see Fujita
and Cook (1990) and references contained therein). Also the northwestern part of the Chukchi
Sea is crossed by eight U.S. Geological Survey multichannel seismic reflection (MCS) profiles
(Grantz et aI., 1986, 1990). In 1989,1990, and 1993-1994 several seismic lines were acquired
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, 667-682.
Margin Derived from Satellite Gravity and Multichannel Seismic
Reflection Data
S.S. Drachev l ,2, G.L. Johnson 3 , S.W. Laxon 4 , D.C. McAdoo 5 and H. Kassens 2
(1) P.P. Shirshov Institute of Oceanology, 36 Nakhimovsky Prospekt, I178S1 Moscow, Russia
(2) GEOMAR Forschungszentrumfiir marine Geowissenschaften, Wischhofstrasse 1-3, D 24148 Kiel,
Germany
(3) University of Alaska, Fairbanks, Alaska 9977S-7220, USA
(4) University College London, Space and Climate Physics Department, MSSL, Holmbury St. Mary, Dorking
Surrey, RHS 6NT, UK
(5) NOAA, NODC, LSA, Silver Spring, MD 20910, US
Received I May 1997 and accepted in revised fonn 16 September 1997
Abstract - This paper presents an analysis of the altimeter derived marine gravity data and
available multichannel seismic reflection profiles of the northeastern Siberia continental
margin to provide a preliminary delineation of its geologic structure. Both data sets allow
making a suggestion that the continental margin was strongly affected by the rifting
process since mid of Mesozoic. The main rift zones extend south- and southeastward from
the shelf edge toward the mainland. These are the Laptev Rift System, New Siberian and
ViI 'kitskii rifts in the East Siberian Sea, and North Chukchi rift basin in the Chukchi Sea.
These structures may represent both active and aborted rifts related to extension episodes in
the Arctic Ocean, namely: initial rifting in the Canada Basin (Middle Jurassic to
Hauterivian), opening of the Makarov Basin (53-80 Ma ?) and spreading in the Eurasia
Basin (0-56 Ma). Thus it is suggested that the spreading migrated westward during the
Cretaceous-Cenozoic time and led to separation and fragmentation of the continental blocks
(Lomonosov and Mendeleev ridges, Chukchi Plateau) and subsidence of the rift basins on
the eastern Russian Arctic continental margin.
Introduction
The Arctic Ocean is unique among the oceans of the world in that half of its area is underlain by
continental shelf, primarily the wide European and Siberian continental shelves. The Laptev,
East Siberian and Chukchi seas overlie the extensive shelf of northeaster Russia which is up to
800 km wide and totals about 2,000,000 km 2 in area (Figure 1). To the north, this continental
margin is bordered by the Eurasia and Amerasia oceanic basins which contain large submarine
ridges and plateaus including: the Gakkel, Lomonosov, Alpha-Mendeleev and Chukchi
Borderland.
The structure and tectonic history of the shelf are very poorly known and are primarily a
postulated extension of the terrestrial geology of the New Siberian, De Long and Wrangel
islands and the mainland (Vinogradov et aI., 1977; Vinogradov, 1984; Fujita and Cook, 1990;
Kos 'ko, 1984; Kos 'ko et aI., 1990). Of the three seas, the Laptev Sea is better known as the
result of the Russian seismic reflection studies which have defined the rift basins (Ivanova et
aI., 1990; Drachev et aI., 1995a). The structural pattern and geological history of the remainder
of the continental margin are still largely unknown and there are as many points of view as there
are investigators. Since beginning of the 1970s, the Russian airborne magnetic data were the
primary available means of deciphering the geology of this region (for more detail see Fujita
and Cook (1990) and references contained therein). Also the northwestern part of the Chukchi
Sea is crossed by eight U.S. Geological Survey multichannel seismic reflection (MCS) profiles
(Grantz et aI., 1986, 1990). In 1989,1990, and 1993-1994 several seismic lines were acquired
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, 667-682.