These datasets describe a 31.5 m long sediment core taken from beneath thermokarst lake Goltsovoye Lake (71.74515 N, 129.30217 E) on the Bykovsky Peninsula, northeastern Siberia. The thermokarst lake was 510 cm deep. Here, we report the depths from the ice surface as well as from the sediment surface.This dataset presents the n-alkane data from samples from sediment core PG2412. Concentrations of n-alkanes in the range n-C23 to n-C33 are given in µg/g sediment and µg/g TOC. From the n-alkane concentrations, we calculated the following indices: average chain length (ACL), carbon preference index (CPI), odd-over-even predominance (OEP), n-Alkane ratio, aquatic plant proxy (Paq) and terrestrial plant proxy (Pwax).