Potential field data of the Barents and kara seas — Reevaluated
|Location||International Geological Congress,oslo 2008|
|Author||Werner, Stephanie C.۱; Ebbing, Joerg۱; Litvinova, Tamara۲; Olesen, Odleiv۱|
|Holding Date||05 October 2008|
Within the GeoBaSe (Geological Evolution of the Barents Sea Region) project, Russian and Norwegian partners synthesize existing geological and geophysical data for the Barents and Kara Seas, and are intending a joint interpretation. Previously, many studies of the Barents Sea Region were limited to either the Norwegian or the Russian part.
Structurally, the Barents Sea is characterized by basins, highs, subsidence rifting, and varying sedimentary load. Crustal thickness and upper mantle structure are still not fully understood, even though processes such as rifting in the Western Barents Sea due to the opening of the North Atlantic, and extensional features in the Eastern Barents Sea are observed. A new compilation of potential field data (and of palaeogeographic maps) provides a new fundament to constrain the basin architecture and crustal pattern of the Barents Sea region.
First steps in this investigation are merging and evaluating the gravimetric data, which includes conversion between the geodetic reference systems. Evaluation of earlier gravity compilations, especially in the northern part of the Barents Sea, revealed the lack of reliable absolute tie points. Misfits of about 10 mGal are observed when compared with independent data compilations or at the long wavelengths with geoid models. Most recent satellite gravity models of the polar region support the revised levelling of the available database. We will present the new compiled maps and preliminary interpretation of the crustal architecture of the Barents Sea Region.
To produce the aeromagnetic anomaly map, the geomagnetic reference field has to be reduced. Here, the main processing difference between the different data sets is the applied reference model. Again, it is an uncertainty, which is reflected in the longest wavelength pattern of the resulting crustal anomaly map data. High-resolution datasets from the Norwegian and Russian surveys complement the existing compilations such as Arctic Gravity Project or for the Magnetic Anomalies of the Arctic compilation.