Abstract
We here present BARENTS50, a new 3D geophysical model of the crust
in the Barents Sea region. The target region of interest comprises
northern Norway and Finland, parts of the Kola Peninsula and the
East European lowlands. Novaya Zemlya, the Kara Sea and Franz-Josef
Land terminate the region to the east, while the Norwegian-Greenland
Sea marks the western boundary. In total, 680 one-dimensional seismic
velocity profiles were compiled, mostly by sampling 2D seismic velocity
transects, from seismic refraction profiles, every 25 km. Seismic
reflection data in the western Barents Sea were further used for
density modeling and subsequent density-to-velocity conversion. Velocities
from these profiles were binned into two sedimentary and three crystalline
crustal layers. The first step of the compilation comprised the layer-wise
interpolation of the velocities and thicknesses. Within the different
geological provinces of the study region, linear relationships between
the thickness of the sedimentary rocks and the thickness of the remaining
crystalline crust are observed. We therefore used the separately
compiled (area-wide) sediment thickness data to adjust the crystalline
crustal thickness according to the sedimentary thickness where no
constraints from 1D velocity profiles existed. The BARENTS50 model
is based on an equidistant hexagonal grid with a node spacing of
50 km. The P-wave velocity model was used for gravity modeling in
order to obtain 3D density structure in the study region. A better
fit to the observed gravity was achieved using a grid search algorithm
which focused on the density contrast of the sediment-basement interface.
The high resolution of 50 km is an improvement compared to older
geophysical models.
Users
Please
log in to take part in the discussion (add own reviews or comments).