A new gravity model of the crustal structure of the Trans-European
Suture Zone in the northwestern
Poland has been constructed. The Bouguer anomaly map, obtained after stripping
off the three-dimensional
gravity effect of the sedimentary cover down to the Zechstein formations,
is
characterized by a 50 mGal
gravity anomaly. We have assumed that the short-wavelength components derive
from upper crustal intrusions
and the long-wavelength components reflect crustal thickness and lateral
heterogeneity which are strongly supported
by the new seismic data along the LT-7 geotraverse. Quantitative modelling
of
gravity data along three
profiles crossing the area indicate the presence of anomalous masses within
the Lower Palaeozoic sequence,
mainly along the Teisseyre-Tornquist Zone. Two of the profiles crossing
the
long-wavelength ‘stripped’ gravity
high suggest the existence of a zone of 35 km crust above a dense upper
mantle
along the Teisseyre-Tornquist
Zone. The extent of the zone can be determined based on the Bouguer anomalies
interpretation.
Three-dimensional gravity inversion model of the deep crustal structure of the central Drake Passage (Shackleton Fracture Zone and West Scotia Ridge, Antarctica)