Hydrochemistry and isotopic signatures of subpermafrost groundwater discharge along the eastern slope of the Lena River Delta in the Laptev Sea

Alexander N. Charkin, Irina I. Pipko, Galina Yu. Pavlova, Oleg V. Dudarev, Andrei E. Leusov, Yuri A. Barabanshchikov, Kseniia P. Shcherbakova, Elena I. Yaroshchuk, Svetlana P. Pugach, Timofey A. Gulenko, Vladimir A. Goriachev, Igor P. Semiletov, Natalya V. Zarubina

Research output: Contribution to journalArticle

Abstract

Geochemical processes in the Artic are changing at accelerated rates due to climate change. We present the results of a study on the features of the isotopic and hydrochemical signals of discharging submarine subpermafrost groundwaters on the transect along the underwater extension of the Lena River Delta in the Laptev Sea. This study demonstrated that the water column at submarine groundwater discharge sites is enriched with radium isotopes. A significant part of the short-lived radium isotopes depending on the season and hydrometeorological conditions can has an erosive genesis, while 226Ra activity is due to the serious contribution of groundwater. The light signal of δ18O and the increased quantities of excess deuterium can indicate that groundwater was formed when the climate was colder than today. The fraction of subpermafrost groundwater in the bottom layer of the studied transect reaches 7% at the plays of the submarine groundwater discharge. The groundwater presence was also indicated by an increase in the content of dissolved Na+ at the discharge site resulting in Ca2+/Na+ ratio decrease relative to other waters in the Buor-Khaya Bay. The higher total alkalinity value is probably also the result of submarine subpermafrost groundwater discharge.

Original languageEnglish
Article number125515
JournalJournal of Hydrology
Volume590
DOIs
Publication statusPublished - Nov 2020

Keywords

  • Isotopic composition
  • Lena River Delta
  • Major ions
  • Permafrost
  • Radium isotopes
  • Total alkalinity

ASJC Scopus subject areas

  • Water Science and Technology

Fingerprint Dive into the research topics of 'Hydrochemistry and isotopic signatures of subpermafrost groundwater discharge along the eastern slope of the Lena River Delta in the Laptev Sea'. Together they form a unique fingerprint.

  • Cite this

    Charkin, A. N., Pipko, I. I., Yu. Pavlova, G., Dudarev, O. V., Leusov, A. E., Barabanshchikov, Y. A., Shcherbakova, K. P., Yaroshchuk, E. I., Pugach, S. P., Gulenko, T. A., Goriachev, V. A., Semiletov, I. P., & Zarubina, N. V. (2020). Hydrochemistry and isotopic signatures of subpermafrost groundwater discharge along the eastern slope of the Lena River Delta in the Laptev Sea. Journal of Hydrology, 590, [125515]. https://doi.org/10.1016/j.jhydrol.2020.125515