Cenozoic Evolution of the Eurasia Basin Based from Analysis of Potential Field and Bathymetry Data
Vladimir Glebovsky1, Valery Kaminsky1, Alexander Minakov2, and Andrey Chernyh1
1VNIIOkeangeologia, St.-Petersburg, Russia.
2Earth and Science Department, University of Bergen, Bergen, Norway.
The geohistorical analysis of the magnetic anomalies, as well as specific features of the gravity field and sea-bottom topography, has confirmed that the Eurasia Basin (EB) was formed owing to spreading of the sea bottom during three stages that differed in their kinematic characteristics. The spreading was begun about 58 Ma ago. It was preceded by the period of extension and rifting related to the continuous opening of the North Atlantic and Labrador Sea.
The EB’s opening predated the spreading in the Norwegian-Greenland Basin and, at the initial stage, was connected with the opening of the Labrador Sea. The basins were connected via the Nares Strait and this link existed until the cessation of spreading in Baffin Bay.
The formation history of the EB was complicated by the northward drift of Greenland relative to North America that commenced approximately 53 Ma ago or somewhat earlier. This motion was provoked by the opening of the North Atlantic to the north of the Charlie-Gibbs Transform Zone simultaneously with the opening of the Labrador Sea. Greenland, moving northward, intruded into the space prepared by extension in the EB. As judged from temporal changes in the configuration of magnetic isochrones, the bottom of this basin was subjected to longitudinal compression for at least 100 km.
Since the onset of spreading in the EB, a large plateau that combined the present-day Yermak Plateau and Morris Jesup Rise has been a part of the Eurasian margin. The drift of Greenland terminated presumably 40-35 Ma ago. The connection between the spreading axes of the Labrador Sea and EB was interrupted about 33 Ma ago. After that event, Greenland became a part of the North American Plate. The divergent plate boundary that broke a formerly common uplift into the present day Yermak Plateau and Morris Jesup Rise arose north of the Norwegian-Greenland Basin. Further opening of the EB was related to the North Atlantic and proceeded along a single axis located nowadays in the Gakkel Ridge rift zone.
In terms of their temporal and kinematic parameters, the main stages of the EB evolution are broadly consistent with the stages of the opening of the Central and North Atlantic as well as adjacent Arctic basins.
AAPG Search and Discover Article #90096©2009 AAPG 3-P Arctic Conference and Exhibition, Moscow, Russia