KRAWCZYK, C. M., and T. McCANN
GeoForschungsZentrum Potsdam, Germany

Abstract: Caledonian Accretion In The Southern Baltic Sea: Constraints From Deep Reflection Seismic Profiling

Important tectonic lineaments north of the Northeast German basin (e.g. Trans-European Suture Zone, Tornquist Zone, Caledonian Deformation Front) are investigated in the southwest Baltic Sea to decide how and when Paleozoic and Mesozoic units were attached to Precambrian Europe. While continental Europe shows clear changes in crustal depth and mantle velocity, the situation in the Baltic Sea is much more complex, where Mesozoic fault zones, inversion structures and Caledonian thrusts from Avalonia onto Baltica are observed.

The recently-acquired DEKORP/BASIN'96 deepseismic profiles in the Baltic Sea locate the northern boundary of the Northeast German Basin, part of the Central European Basin System. The reflection seismic data further confirm the idea of a bivergent collision between Avalonia and Baltica, and reflections in the uppermost mantle are interpreted as traces of the Tornquist Ocean subduction. Similar style of compression is also observed in the Proterozoic crust farther north, and seems to be connected to major tectonic lineaments.

AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas