Average δ¹⁸O values in syngenetic ice wedges of Siberia are investigated.The oxygen isotope composition in the Late Pleistocene ice wedges change from the west to the east by 8–10 ‰: δ¹⁸O values vary in Western Siberia from –19 to –25 ‰, in Northern Yakutia from –30 to –35 ‰, in the north of Chukotka from –28 to –33 ‰, in the south of Chukotka from –23 to –29 ‰.

Stable isotope analyses were made at the isotope laboratory of the Institute of Water Problems RAS (Dr. A.Yesikov) using a Finnigan MAT 250 mass spectrometer, analytical precision was ±0.6‰ and at the Tallinn Institute of Geology (Prof. R. Vaikmäe), analytical precision was ±0.4‰.