Field guide - IUGS

Fig.3.6. Location map showing the study areas along The White Sea coast. Areas where
raised coastal lake basins was studied: 1 –Lesozavod area; 2 – Umba area; 3 - Varzuga area;
4 - Chapoma area; 5 – Likhodeevka area. The line of morphological profiles: K –
Kandalaksha; T –Tury Peninsula, Kb – Korabl' Cape; P –Pulon'ga River
Various facies types and facies sequences controlled by relative sea-level change and
also by climatic factors are recognized in the cores. Facies types are: (I) glacial lake (nonlaminated
clay), (II) mixed, lateglacial sea ingression, (silt and sand with plant detritus), (III)
marine (mud silt, sand, shells/shell fragments), (IV) transitional (laminated or non laminated
gyttja and silt), (V) lacustrine (gyttja, plant detritus).
There were determined the diatom complexes corresponding to:
- stage I, glacial lake (solitary freshwater species Aulacoseira islandica, Pinularia
isostauron and fragments of marine ones);
- stage II, lateglacial sea ingression (interbedded layers with predominance of
mesogalobous Coscinodiscus lacustris var.septentrionalis and layers enriched by halophilous
Rhopalodia gibba var.vantricosa);
- stage III, marine (with predomination of polyhalobous and mesohalobous);
- stage IV, transitional stage (mesohalobous and halophilous);
- stage V, stage of contemporary freshwater lakes (with domination of indifferentes
and halophodous).
The position and the age of the shoreline of transgressing sea correspond to the position and
age of the facies II sediments, and of regressing sea to the facies IV sediments (Fig. 3.7).
Cores from different investigated areas show complicated facies sequences comprising either
all facies types or only a few facies types. The factual evidence for the shorelines
reconstruction in the Kandalaksha bay was obtained during the study of the lake basins in the
Umba area (places 2 in Fig. 3.6).
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