Title

V. I. Astakhov, D. V. Nazarov, L. R. Semenova, M. A. Spiridonov, V. K. Shkatova

On mapping problems of the Northern Pleistocene

Stratigraphic and sedimentologic problems connected with cartographic images of surficial terrigenous formations of the Russian North are discussed. Deterioration of quality of national Quaternary maps in scales 1 : 1 000 000 and 1 : 200 000 is noticeable for the last two decades. This is due to the break with the tradition of classical Quaternary geology developed and maintained in VSEGEI. The main deficiency of many new maps is caused by erroneous genetic diagnosis of terrestrial sediments and arbitrary determination of their age based on mixed associations of redeposited organic remains. Modern sedimentological and geochronometric data neither confirm marine origin, nor the Neogene age of diamicts with megaclasts which, as in other circumpolar regions, are predominantly Pleistocene formations. Also, the negation of the climatostratigraphic principle leads to improbable correlations of northern sequences with Southern and West European records. Especially bad for the map quality is the so-­called `level hypothesis` ascribing different stratigraphic values to various stairs of flatland topography. This concept is falsified by the direct observations in long shoreline sections. The rejection of glacial genesis of diamictic formations leads to futile indicator tracing. This paper, however, presents additional unambiguous evidence of glacial origin of the bulk of the Northern Pleistocene in the form of geological profiles, remotely sensed images of the uppermost Pleistocene strata and photos of buried glaciers.
Key words: National geological map, Northern Pleistocene, climatostratigraphy, diamictic strata, megaclasts, geochronometry.