Geological Survey of Finland, Special Paper 46 - arkisto.gsf.fi

Applied Quaternary research in the central part of glaciated terrain,
edited by Peter Johansson and Pertti Sarala.
Geological Survey of Finland, Special Paper 46, 79–86, 2007.
PROGLACIAL SEDIMENTARY ENVIRONMENT IN
PÄRNU AREA, WESTERN ESTONIA AS DERIVED FROM
THE VARVED CLAY STUDIES
by
Tiit Hang, Peeter Talviste, Raul Reinson and Marko Kohv 1
Hang, T., Talviste, P., Reinson, R. & Kohv, M. 2007. Proglacial
sedimentary environment in Pärnu area, western Estonia as derived
from the varved clay studies. Applied Quaternary research
in the central part of glaciated terrain. Geological Survey of Finland,
Special Paper 46, 79–86, 5 fi gures, 1 table.
Distribution, grain-size and varve thickness data of the
Late Weichselian varved clays have been analysed to describe
the sedimentary environment and the ice sheet recession at the
distal position of the Pandivere–Neva (13,500–13,300 yrs BP)
ice-marginal formations, western Estonia. Dominating clay and
silt fractions and very low sand content refl ects an infl ow of
mainly fi ne-grained material. Vertical changes in grain-size are
characterised by the decrease of clay content and increase of silt
content towards the depth. Gradually decreasing upwards total
varve thickness and characteristic changes in relation to seasonal
layer thicknesses within each varve refl ect normal sedimentation
in the proglacial lake where, at each point, proximal conditions
gradually changed to more distal conditions. There is no evidence
from the varve clay studies pointing to the stagnation or
readvance of the ice terminus prior or during the formation of the
Pandivere–Neva ice marginal formations.
Key words (GeoRef Thesaurus, AGI): glaciolacustrine sedimentation,
clay, varves, grain size, thickness, deglaciation, Pleistocene,
Weichselian, Pärnu, Estonia.
1 Institute of Geology, University of Tartu, Vanemuise 46,
EE-Tartu, Estonia
E-mail: Tiit.Hang@ut.ee, Peeter@geotehnika.ee,
Reinson@ut.ee, Marko.Kohv@ut.ee
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