Stable isotopes of Kotelny Island were measured at the Isotope Laboratory of the Faculty of Geography of Moscow University. The analysis was performed on a Finnigan Delta-V Plus mass spectrometer with a standard gas-bench option and the results were calibrated against international (V-SMOW and SLAP) and laboratory standards, with internal 1σ errors of ±0.6 ‰ for δ2Н and ±0.1 ‰ for δ18O, jf Bolshoy Lyakhovsky and Bunge Islands in the isotope laboratory of the Institute for Polar and Marine Research Alfred Wegener, Potsdam using mass-spectrometer Finnigan MAT Delta-S. Measurement errors of oxygen are ±0.10‰. δ¹⁸O values in modern incipient syngenetic ice wedges in islands of Russian East Arctic, modified and complemented after Vasil'chuk, (1992).