TY - JOUR

T1 - Chronologies of active growth of ice wedges and Middle Holocene palaeoclimate at Lorino site, Chukchi Peninsula, easternmost Siberia

AU - Васильчук, Юрий Кириллович

AU - Буданцева, Н.А.

AU - Васильчук, Алла Константиновна

AU - Маслаков, А.А.

AU - Токарев, Игорь Владимирович

AU - Васильчук, Джессика Юрьевна

AU - Кузякин, Л.П.

N1 - Vasil’chuk YK, Budantseva NA, Vasil’chuk AC, et al. Chronologies of active growth of ice wedges and Middle Holocene palaeoclimate at Lorino site, Chukchi Peninsula, easternmost Siberia. Radiocarbon. Published online 2024:1-8. doi:10.1017/RDC.2024.108

PY - 2024/12/6

Y1 - 2024/12/6

N2 - AMS radiocarbon ages of organic matter from ice wedges and enclosing peat were determined for the polygonalpeatland at the Lorino site on the eastern coast of the Chukchi Peninsula. The study’s goal was to fill a knowledgegap about the dynamics of polygonal peatlands with ice wedges and winter climate conditions during the Holocenein this easternmost region of the Russian Arctic. It has been found that peatland accumulated during the YoungerDryas and early Holocene, mostly between 14 and 9.9 cal ka BP, while ice wedges were dated from 7.7 to 6.6 cal kaBP. Since ice wedges have features of syngenetic growth, the discrepancy in the age of ice wedges and enclosingpeatland may result from the significant presence of early and pre-Holocene peat. It is assumed that the olderpolygonal peatland deeply thawed during the Holocene optimum, and subsequently, when the permafrost aggraded,a new generation of ice wedges was formed. The AMS 14C age (18.1 cal ka BP) of the ice wedge exposed below thepeat indicates the presence of a Late Pleistocene generation of ice wedges at the study site. Paleotemperaturereconstructions based on the stable isotope composition of ice wedges show that the mean January air temperatureduring the Northgrippian stage of the Holocene varied from –27 to –23°C, and at the end of the Late Pleistocene,from –32 to –26°C.Kuzyakin L.P. .

AB - AMS radiocarbon ages of organic matter from ice wedges and enclosing peat were determined for the polygonalpeatland at the Lorino site on the eastern coast of the Chukchi Peninsula. The study’s goal was to fill a knowledgegap about the dynamics of polygonal peatlands with ice wedges and winter climate conditions during the Holocenein this easternmost region of the Russian Arctic. It has been found that peatland accumulated during the YoungerDryas and early Holocene, mostly between 14 and 9.9 cal ka BP, while ice wedges were dated from 7.7 to 6.6 cal kaBP. Since ice wedges have features of syngenetic growth, the discrepancy in the age of ice wedges and enclosingpeatland may result from the significant presence of early and pre-Holocene peat. It is assumed that the olderpolygonal peatland deeply thawed during the Holocene optimum, and subsequently, when the permafrost aggraded,a new generation of ice wedges was formed. The AMS 14C age (18.1 cal ka BP) of the ice wedge exposed below thepeat indicates the presence of a Late Pleistocene generation of ice wedges at the study site. Paleotemperaturereconstructions based on the stable isotope composition of ice wedges show that the mean January air temperatureduring the Northgrippian stage of the Holocene varied from –27 to –23°C, and at the end of the Late Pleistocene,from –32 to –26°C.Kuzyakin L.P. .

KW - Radiocarbon AMS dating

KW - ice wedge

KW - Holocene

KW - peat

KW - oxygen isotopes

U2 - 10.1017/RDC.2024.108

DO - 10.1017/RDC.2024.108

M3 - Article

JO - Radiocarbon

JF - Radiocarbon

SN - 0033-8222

ER -