The Kola region includes the Kola Peninsula and adjacent shelves of the Barents and White seas. The research carried out by the author has shown that the marine sediments underlying till of the Late Valdai glaciation in the east of the peninsula make two formations divided by an erosional surface. The lower formation is called the Ponoi strata and the upper one - the Strelna strata, following the local names for the key sections.

The Ponoi strata contain plenty of marine mollusk shells, foraminifera and diatoms together with pollen and spores. The palaeontologic assemblages indicate that the Ponoi strata started to form in a severe climate. However, at the initial stage of the sea regression typical interglacial climates, more favorable than the present ones, prevailed. At the peak of the transgression sea level was 150 m higher than today, and at the subsequent regression it dropped at least to the mark of с 10 m. According to the uranium-ionium dates of mollusk shells (Evzerov, Koshechkin, 1977; Arslanov et al, 1981) and the subsequent dating of shells and sand by electron spin resonance (ESR) and optically-stimulated luminescence (OSL) (Molodkov, Yevzerov, 2004; Korsakova et al, 2004) the Ponoi strata must belong to the Mikulino (Eemian) interglacial.

The Strelna strata contain much less fossils. They formed in a climate more severe than the present one, and therefore should relate to an interstadial. At the peak of transgression sea level exceeded 70 m. Shells of marine mollusks and enclosing sediments are dated by ESR and OSL methods (Korsakova et al, 2004). The ages obtained (about 80-100 kyr BP) correspond to MIS 5d-5a, probably to the Early Valdai. However, at two sites, apparently not different from other Strelna sections in terms of palaeonthology, the dated sediments yielded Middle Valdai age values с 59 to 44 kyr BP, i.e. MIS 3. These datings are obviously insufficient for suggesting a new, third sea transgression. The implication that the Strelna transgression occurred just after the regression of the Eemian sea is hard to reconcile with other Late Pleistocene events either.

Palynologically the Strelna strata are similar to the lacustrine sediments of the Kovdor vicinity and deposits of the Maaselka/Perapohjola interstadial of Northern Finland (MIS 5a) dated by radiocarbon method to more than 50 and 42 kyr BP, respectively (Yevzerov et al, 1998; Helmens et al, 2000). They were formed under predominance of forest-tundra vegetation. This is an argument in favor of correlation of these sediments with the Odderade (MIS 5 a) and not with younger interstadials, which at the southern flank of the Scandinavian ice sheet were characterized by tundra vegetation (Hammen et al, 1971).

Reference:

Yevzerov. V.Ya. Late Pleistocene marine transgressions in the Kola region. Correlation of Pleistocene Events in the Russian North. International Workshop Abstracts. 4-6 December 2006. Saint-Petersburg, 2006, p. 108.