PLUTONIC STRUCTURE OF THE SPITSBERGEN MARGINAL PLATEAU IN THE NORTHEASTERN PART OF THE GREENLAND SEA

Abstract

Plate tectonics suggest that the first stage of rifting in the areas of the Norwegian Sea and of the present southern part of the Greenland Sea, and in the Eurasian deep-sea basin, began about 60 million years and ended 36 million years ago. Greenland was displaced to the northwest, moving past the Barents Sea margin of the Eurasian plate along a system of transform faults that connected the mid ocean Mohns Ridge in the south with the Nansen Cordillera a mid-ocean ridge in the north. The Hornsund Fracture Zone on the outer shelf of West Spitsbergen is one of these faults. About 36 million years ago a new tectonic stage began, with Greenland moving westward and the North American and Eurasian plates separating as the northern part of the Greenland Sea opened and a deep-sea rift developed in the area between the Eurasian Arctic basin and the Norwegian-Greenland Sea. The result was formation of a spreading center, the Knipovich Ridge.