Holocene Palsa Evolution near the Eletsky village using Stable Isotope Tracers and Radiocarbon Dating (Part 1. Cryostratigraphy, Stable Isotope Distribution, and Radiocarbon Age)

The Eletsky palsa massif, located in the northeast of the Bolshezemelskaya Tundra within the continuous permafrost zone, has been the subject of study. Approximately ten palsas of varying sizes and evolution stages were examined, including tall, mature frost mounds reaching heights of 3 to 5 meters, low (likely growing) palsas around 1.5 meters high, and decaying palsas approximately 2 meters in height. The primary aim of this research is to compile findings from a comprehensive analysis of the palsas, focusing on the radiocarbon age of the peat, the isotopic composition of oxygen and hydrogen in the ice of the frozen core, and the nitrogen and carbon content of the overlying peat. Results from radiocarbon dating indicate that the formation of the palsas did not occur simultaneously. The peat from Palsa 1 is dated between 8.9 and 4.9 cal ka BP. Palsa 2's peat is dated from 7.4 to 3.7 cal ka BP. The oldest date obtained for the lower part of the peat cover on the largest Palsa 3, is 9.1 cal ka BP. The peat of the lower Palsa 4 ranges from 7.3 to 1.6 cal ka BP. At the destroyed Palsa 5, peat on the ring shaft is dated from 8.2 to 2.8 cal ka BP. Peat of Palsa 6 is dated from 6.4 to 5.6 cal ka BP. A non-inversion series of ¹⁴C dates was obtained from the peat of Palsa 7 – from 9.1 to 4.9 cal ka BP. Several dates from 11.1 to 3.3 cal ka BP were obtained for the peat of Palsa 8. ¹⁴C dates from 7.1 to 5.5 cal ka BP have been obtained for the peat of Palsa 9. The δ¹⁸O values in the ice from the upper part of the icy core of the palsas vary from –16.5 to –13.7‰, while δ²H values range from -114.4 to -87.4‰. The carbon content in the peat fluctuates between 43% and 54%, and nitrogen levels range from 1.1% to 3.2%. The δ¹³C values in the peat are between –28% and –32‰, with an average around –30‰. The δ¹⁵N values in the peat overlying the palsas typically fall between 1‰ and 3‰.