Abstract: Geology of Norwegian Continental Shelf North of 62°North

Hans Chr. Ronnevik

Since 1969 regional geophysical mapping has been undertaken on the Norwegian shelf north of 62°N. Approximately 38,400 km of regional reflection-seismic profiles have been shot. Detailed surveys were made in selected areas offshore from Troms and More.

The Norwegian offshore north of 62°N can be separated into the More-Lofoten and the Barents Sea areas. The More-Lofoten shelf, stretching from 62 to 69°30^primeN, is separated geomorphologically into three segments. A similar separation also is reflected in the land geomorphology and the structural geology underlying the shelf and slope. The shelf has the characteristics of a passive continental margin. The pre-Tertiary sedimentary rocks are structured into three subbasins.

The Barents Sea is an epicontinental sea with water depths averaging 300 m and a gentle bottom topography. Close to the coast, outside Troms, the transition between sedimentary rocks and basement is marked by a change to a rougher topography. Outside Finnmark the wedgeout of the sedimentary rocks under the sea against the old Precambrian land bed rock is affected by a trench.

The eastern part of the Norwegian Barents Sea is a broad epeirogenic basin but more complex structural conditions are present in the western part. The transition between the Barents Sea and the oceanic Norwegian Sea is marked by a Tertiary clastic wedge. A north-south high complex underlies the wedge. In the north-south basin, east of the high, are several salt diapirs. The basin is bordered on the east by a hinge line. Salt diapirs also are present in the eastern Barents Sea.

AAPG Search and Discovery Article #90972©1976 AAPG-SEPM Annual Convention and Exhibition, New Orleans, LA