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intense faulting in the Baltic region, the soft docking of East Avalonia and Baltica
did not result in any significant faulting of the Baltic region.
2.3.4 Intracratonic Basin Stage
The foreland subsidence stage with high subsidence rates was followed by more
stable tectonic conditions and continuous but much slower subsidence during the
Devonian. The subsidence pattern changed considerably. Maximum subsidence
rates occurred in the central part of the Baltic region, where the thickness of the
Devonian succession reaches up to 1.1 km. Results of subsidence backstripping
(Figs. 2.6 and 2.7 ) show that the calculated tectonic subsidence is accountable only
for roughly 300 m of the total subsidence during that time. Driving mechanisms
for the basin subsidence are so far not completely understood. It is presumed that
larger scale processes influencing the whole East European platform have also trig-
gered the subsidence (e.g. Ismail-Zadeh 1998 ) . This hypothesis is mainly justified
by the similarities in sedimentation and subsidence trends between the Baltic and the
Moscow basins (McCann et al. 1997 ) . Nevertheless, the Baltic basin was also influ-
enced by compressive tectonic forces related to the Variscan deformation processes
in the western part of Europe (Šliaupa 2004 ) .
2.3.5 Thermal Doming and Thermal Sag Stage
The subsidence ceased at the beginning of the Carboniferous and the subsequent
period of basin development was characterized by a break in sedimentation until the
Middle/Upper Permian. Furthermore, the basin flanks were considerably uplifted
and eroded.
Numerous diabase sills and dykes of Permocarboniferous age are known from
the southern and the central part of the Baltic Sea basin (Motuza et al. 1994 ) aswell
as from Scania, Bornholm and the Rügen area in the west (Obst 2000 ) . The chemical
composition of the diabases has an affinity to rift-related intrusions. This hints of a
tectonic reactivation of the Baltic Sea area. The corresponding lithosphere heating is
accounted for the uplift of the basin during the Permocarboniferous thermal doming
stage.
The following thermal relaxation led to the re-establishment of the subsidence
regime and sedimentation during Late Permian time (Fig. 2.5 ) . Subsidence took
place especially in those areas which were uplifted before, in particular the Mazury
High. This is a clear hint for the involvement of thermal sag processes as major
subsidence-driving mechanism. The thermal sag is coupled with some wrench fault
movements along the craton margin. These mechanisms were most active in Late
Permian and Early Triassic time and gradually ceased throughout the Mesozoic
and the Cenozoic. Therefore only episodic sedimentation related to global sea level
changes occurred in the Baltic basin during that time. Only in the southwestern part
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