Arctic GIS Workshop Poster Abstract

22-24 January 2001
Bell Harbor International Conference Center
Seattle, Washington

Tectonics of the Basement and Sedimentary Basins of the Laptev and East Siberian Seas, Russian Arctic

Sergey B. Sekretov (Marine Arctic Geological Expedition, Murmansk, Russia)
Vernadsky State Geological Museum, Russian Academy of Sciences, Mokhovaya str 11 Bldg 2 Moscow, 103009 Russia, Phone: +7-095/292-0586, Fax: +7-095/292-0586, rwm@sgm.ru

No deep boreholes are available from the continental margins of the Laptev and East Siberian Seas. In the absence of drilling data, the geology of the adjacent land and complex interpretation of the geophysical data may provide with the clues, at least, to the nature of the continental basement. The interpretation of seismic reflection data is the major method to study the sedimentary basins of continental margins. This paper summarizes the geological interpretation of a regional 2D seismic survey carried out by Marine Arctic Geological Expedition (MAGE) of Murmansk, Russia in 1986 -1990. A part of the seismic reflection data obtained by other companies also was incorporated in the structural compilations. The seismic stratigraphic interpretation of the sedimentary cover as well as the tectonic zonation of the basement are presented as one possible model. In the opinion of the MAGE researches, the continental shelf includes the offshore continuations of the Siberian Platform in the western Laptev Sea, the Early Mesozoic South Taimyr fold belt in the northwestern Laptev Sea and the Late Mesozoic fold belts of the norheastern Russia in the eastern Laptev Sea and western East Siberian Sea. The seismic data have shown that the mid-ocean Gakkel Ridge, which is a Cenozoic spreading centre in the Eurasian Basin of the Arctic Ocean, "extended" onto the Laptev shelf as a Cenozoic continetal rift zone. The present morphology of the northern shelf and deep margin is the result of continental-terrace progradation and gravity-driven slope processes.