The origin of salts in water bodies of the McMurdo Dry Valleys

• Published in: Antarctic Science
• Main Authors: Takamatsu, Nobuki, Kato, Naoyuki, Matsumoto, Genki I., Torii, Tetsuya
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1998
• Subjects: Victoria Land; McMurdo Dry Valleys; Vanda; Bonney; Fryxell; Labyrinth; Lake Vanda; Don Juan Pond; Antarc*; Antarctic Science; Antarctica
• Online Access: http://dx.doi.org/10.1017/s0954102098000534; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102098000534

Lithium distributions in lake and pond waters of the McMurdo Dry Valleys of southern Victoria Land, Antarctica were studied to elucidate the origin of dissolved salts and the evolutionary history of the lakes and ponds. The Ef Li [(Li/Cl)sample/(Li/Cl)seawater] values of the bottom waters in Lakes Bonney and Fryxell were higher than unity (Ef Li =4–7), indicating that the salts originated from sea salts (probably relict seawater) and have been subsequently modified by the contribution of meltwaters containing atmospheric fallout and/or rock and soil weathering products. In contrast, extremely high Li concentrations with high Ef Li values in the Don Juan Pond water (Ef Li = 180) and the bottom waters of Lake Vanda (Ef Li = 40) suggest that the salts originated from deep groundwaters influenced mainly by saline water-rock interactions, as supported by the dissolution experiments of granite in NaCl solution. The low Li concentrations of pond waters with high Ef Li values in the Labyrinth indicate that the salts are derived from atmospheric fallout. The decrease of the Ef Li values with the increase of Cl concentrations can be explained by the repeated cycles of the migration of Li into the ice phase and subsequent ablation of surface ice, as indicated by seawater freezing experiments.