Abstract

AbstractPerennial frost mounds identified as lithalsas occur in the Sentsa River valley of the Eastern Sayan Mountains, Russia. We report the first detailed study of permafrost in this region, based on analysis of the cryostructure and distribution of stable isotopes of oxygen and hydrogen, and ion concentrations from the ice‐rich cores of two lithalsas 3–7 m high. Their main cryostructures are reticulate and lenticular, with visible ice contents exceeding 50–60%. The vertical and lateral distribution of δ18О and δD values show a step‐by‐step mechanism of lithalsa growth: in the first stage a large lithalsa formed, and in the second stage a small lithalsa formed. The more negative isotope values of ice in the large lithalsa ice probably resulted from gradual release of isotopically depleted water from the central to peripheral part of the massif during ice segregation in water‐saturated fine‐grained lake sediments. Minor variations of isotope values suggest intensive recharge of lake‐fen and meteoric water supply during freezing and lithalsa growth. Copyright © 2015 John Wiley & Sons, Ltd.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.