Isotopic composition of oxygen and hydrogen in ice wedges from the third marine terrace near Lorino settlement on the eastern coast of Chukotka

The study's focus is on Early Holocene syngenetic ice wedges that are exposed in a polygonal peatland's outcrop in the topmost part of the third marine terrace, close to the Lorino village on Chukotka's eastern coast. The peatland accumulation near Lorino village started around 14-13 cal ka BP, at the end of the Younger Dryas, according to the radiocarbon dates that were collected. The active stage of peat accumulation ended around 10 cal ka BP. It is not unusual for peat accumulation to have started near the end of the Younger Dryas, before the Holocene's officially recognized lower limit (11.7 cal ka BP), and to have ended in the midst of the Holocene's Greenlandian stage. The reworking of ancient organic material during the erosion of the marine terrace sediments and separation of the allochthonous peat is most likely the cause of the age inversions in the peat observed along vertical profiles. In the peatland exposure, six fragments with ice wedges were studied between 2015 and 2021. […]