Oxygen and Hydrogen Isotope Compositions of Lithalsa Frozen Core: A Case Study from the Sentsa River Valley, East Sayan

Mineral permafrost mounds (lithalsas) have been studied in the Sentsa River valley (East Sayan Mountains, western Buryatia). This is the first detailed study of permafrost in the area based on analysis of cryostructures and distribution of stable isotopes in lithalsa intrusive-segregation ice. The l...

Full description

Bibliographic Details
Main Authors: Vasil'chuk, Yurij K, Alekseev, S V, Arzhannikov, Sergey G, Alekseeva, L P, Budantseva, Nadine A, Chizhova, Julia N, Arzhannikova, Anastasia V, Vasil'chuk, Alla Constantinovna, Kozyreva, E A, Rybchenko, A A, Svetlakov, A A
Format: Dataset
Language:English
Published: PANGAEA 2020
Subjects:
East Sayan
frost heave
intrusive ice
Lithalsa
reticulate cryostructure
segregated ice
thick ice lens
Ice
permafrost
Permafrost and Periglacial Processes
Online Access:https://doi.pangaea.de/10.1594/PANGAEA.919702
https://doi.org/10.1594/PANGAEA.919702
Description
Summary:Mineral permafrost mounds (lithalsas) have been studied in the Sentsa River valley (East Sayan Mountains, western Buryatia). This is the first detailed study of permafrost in the area based on analysis of cryostructures and distribution of stable isotopes in lithalsa intrusive-segregation ice. The lithalsas predominantly have reticulate or lenticular cryostructures and ice contents over 50-60 %. The lateral and vertical δ¹⁸O and δ²H patterns suggest cascade growth with the large lithalsa formed before the small one. Lithalsas can nucleate and grow during progressive lake shallowing. They feed mainly from ground water during freezing of wet frost-susceptible finegrained soil, or less often, from meteoric or lake water. Lithalsas grow quite rapidly, at tens of centimeters per year, and can reach more than 5 meters high in 50-100 years.

Similar Items