Geoscience Reference
In-Depth Information
Chapter 6
Geological Structure of the Quaternary
Sedimentary Sequence in the Klaipeda Strait,
Southeastern Baltic
Albertas Bitinas, Aldona Damušyte, and Anatoly Molodkov
Abstract The Klaipeda Strait is located between the Curonian Spit and the main-
land coast of Lithuania. It links the Curonian Lagoon with the Baltic Sea. The
Quaternary sequence is represented here by Pleistocene sediments formed during a
few glaciations and interglacials. Its uppermost part is composed of Late glacial and
Holocene sediments originating from different stages of the Baltic Sea development.
One of the main problems of Quaternary geology in the vicinities of the Klaipeda
Strait, as well as in the whole Lithuanian Coastal Area, is the reliable geochronol-
ogy and stratigraphic correlation of sediments. To contribute to the solution of this
problem, the infrared optically stimulated luminescence (IR-OSL) dating of the
lacustrine inter-till sandy sediments was done during the engineering geological
mapping of the Klaipeda Strait. The absolute majority of the IR-OSL ages obtained
for the investigated inter-till sediments fall within the age range of marine isotope
stages (MIS) 5d-5a. The subsequent more detailed examination of geological setting
of Quaternary sequence has led to the assumption that the sampled inter-till sedi-
ments occur not in situ, i.e. they are found as blocks (rafts) in a thick till bed that
have been formed by the ice advance during the Weichselian early pleniglacial max-
imum (MIS 4). This conclusion does not support the former standpoint that the till
beds beneath the bottom of the Klaipeda Strait were formed during the Warthanian
(Medininkai, MIS 6) glaciation.
Keywords Klaipeda Strait
·
Late Pleistocene
·
Till
·
Stratigraphy
·
IR-OSL
dating
·
Glaciodislocations
Search WWH ::




Custom Search