Field guide - IUGS

Fig. 2.8. Lateral meltwater channels crossing the southern part of moraine ridge on N-W
Lovozero Mountains.
Excursion 2: Late Glacial ice-marginal formations in Lovozero area
Degradation of the Late Valdai ice sheet in the Kola region occurred in conditions of arctic
climate with alternating phases of stadial falls of temperature and interstadial warming.
External heat was not enough for the active ice margin to retreat (Yevzerov, 1996). In these
environments, three belts of marginal ridges formed in the region (Fig. 2.9).
The degradation stages of the ice sheet in the Kola region have been correlated to climatic
cycles - Oldest, Older and Younger Dryas, and to the previous interstadial warmings. Note,
each marginal belt was formed during the interstadial-stadial cycle of the glacier activity and
was made up of two bands of marginal ridges: the inner band - dump moraine (marginal
esker), and the outer band - a push moraine. The formation of three outer bands of marginal
ridges corresponds to the three final stages (Oldest, Older and Younger Dryas) of the glacier
activity in the Kola region: Terskaya (13,5 ka), Revdozerskaya (12,5 ka), Kandalakshskaya
(10 - 11 ka).
The inner band - dump moraine formed under interstadial conditions and the outer band -
push moraine formed during followed stadial cooling. The all the belts of marginal ridges are
named after stadial cooling - Terskii, Revdozerskii, Kandalakshskii. Most investigated of
them are the recessive formations related to the Revdozerskaya stage of Scandinavian icesheet
development. In one case (Ekman, Iljin, 1991), the marginal ridges north of Lovozero
Mountains are related to the Younger Dryas (Salpausselka) stage, and south of Lovozero
Mountains - to the Older Dryas (Neva stage). In next case (Yevzerov, 1996), the all the
marginal ridge complexes consist of two bands of the marginal formations and are correlated
to the Older Dryas (Neva) stage.
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