Quaternary deposits of the Verkhoyansk Range and surroundings were studied by a German-Russian project in 2002-2004. The integrated study included dating (IRSL, ¹⁴C/AMS), geomorphological and geocryological research, remote sensing interpretation, and also lithological, stable isotope and palynological analyses. The two selected study areas were situated in the central Verkhoyansk Range on river Tumara, a left tributary to the lower Aldan, and on the Dyanushka, a left tributary to the Lena. In both areas expressive end morainic arcs occur. In addition, previously studied Quaternary sections in the northern Verkhoyansk Range have been dated.

These results suggest a new chronology of glaciations in the Verkhoyansk Range. Altogether five end moraines (I-V) were mapped. The oldest and maximum ice advance far onto the foreland occurred about 135-140 ka BP. The second end moraine has not been dated. Ice advances III and IV have minimum ages of 80-90 ka and ca. 110 ka BP respectively. Glaciers of the last significant ice advance (I), which terminated about 55 ka BP, were contained within the mountains. We specially underline that our data do not support an ice advance during the LGM. Thus, our results are in discrepancy with the previous chronology of glacial history, particularly for the Late Pleistocene (Kind et al, 1971; Kolpakov 1979; Kolpakov, Belova, 1980).

Dates obtained from perennially frozen deposits in river valleys of the northern Verkhoyansk Range, as well as in the adjacent lowland, are in good agreement with the new glacial chronology of the Late Pleistocene. In some dated sequences the datings indicate a continuous sedimentation from Middle Weichselian times to the termination of the Pleistocene and the Holocene. As a rule sedimentation started earlier in the foreland than in the mountain valleys. The basal horizons mostly consist of coarse sands with gravel and debris of local provenance. They are overlain by fine sands and silts containing vascular grass roots, in places plant remains, and in the foreland plain - huge ice wedges. Pollen data indicate shrub tundra and tundra steppe environments and increasingly continental climate during the LGM. The extreme climate apparently explains the absence of significant advances even of alpine glaciers of the Verkhoyansk Range. Data obtained so far suggest that ice advances in the Verkhoyansk Range were not synchronous with those in other parts of Eurasia. Further verification of these findings needs additional dating efforts.

Reference:

Siegert C., Diekmann B., Lehmkuhl F., Popp S., Sergeenko A.I., Stauch G., Belolyubsky I.N. Environmental history of the Verkhoyansk Range and its foreland in Late Pleistocene: results of new investigations. Correlation of Pleistocene Events in the Russian North. International Workshop Abstracts. 4-6 December 2006. Saint-Petersburg, 2006, p. 90.