Geological Evolution and Resources of the Baltic Sea Area from the Precambrian to the Quaternary - The Baltic Sea Basin - page 14

but some hints for neotectonic activities do also exist. Glacial erosional processes
undoubtedly contributed to the shape and depth of the Baltic Sea. Evidences avail-
able today, however, suggest the existence of a pre-existing tectonic depression.
Major resources of the deeper underground of the Baltic basin are oil, gas, geother-
mal energy and reservoir formations which can be used as storage sites (natural gas,
CO 2 , compressed air). Location of known oil and gas fields shows a strong relation
to the major fault zones.

Keywords Baltic Sea · Baltic basin · Geodynamic evolution · Structure ·

Resources · Hydrocarbons

2.1 Introduction

Although the Baltic Sea was formed during Quaternary time, a more detailed look at
the origin of the corresponding morphological low implies that a reactivated ancient
tectonic structure could have been a major factor for its development. The origin of
the Baltic Sea and of the corresponding morphological low is still a matter of con-
troversy, considering it on the one side as an erosional structure and on the other as
a tectonic depression. The different views are summarized by Šliaupa et al. ( 1995b )
and Schwab et al. ( 1997 ) . The debate is not purely academic. It is important to
understand the processes of the formation of the Baltic Sea as a basic frame and
data input for the prognosis of the future development of the Baltic Sea in a changing
environment and for the search of mineral resources.
The Baltic Sea covers the western and the central part of the Baltic sedimentary
basin and is therefore intimately connected to the development of the underlying
basin. The chapter gives a synthesis of the sedimentation and the structural history
of the basin from the Proterozoic to the Cenozoic, focusing on its central part. It
describes important tectonic mechanisms of the basin development and the subsi-
dence history and points out links between the development of both the Baltic Sea
and the underlying sedimentary basin. Within this context the resource potential and
consequences for further exploration are discussed.

2.2 Geological Framework and History of Sedimentation

2.2.1 The Baltic Basin

The Baltic basin (Fig. 2.1 ) is located above the margin of the East European cra-
ton, which was consolidated during the Early Proterozoic (Linnemann et al. 2008 ) ,
except for the westernmost part which was formed during the Mesoproterozoic
(Bingen et al. 2002 , Obstetal. 2004 ) . The thickness of the sedimentary section
is less than 100 m in northern Estonia, increasing to around 1,900 m in southwest