Abstract. Preliminary results of field surveys (July 2025) of the ultra-acid sulfate-chloride thermal springs of the " Blue Lakes" which discharge in the Kipyashchiy Stream valley on the slope of the active Baransky volcano (Iturup Island, Southern Kuril Islands), are presented.

For citation: Degterev A.V., Romanyuk F.A. Field study of the ultra-acidic thermal springs "Blue Lakes" on Baransky volcano (Iturup Island, Southern Kuril Islands) in 2025. Geosistemy perehodnykh zon = Geosystems of Transition Zones, 2025, vol. 9, No. 4, pp. 478–484. (In Russ.).
https://doi.org/10.30730/gtrz.2025.9.4.478-484, https://www.elibrary.ru/scfbav

Для цитирования: Дегтерев А.В., Романюк Ф.А. Полевые исследования ультракислых термальных источников «Голубые озера» на вулкане Баранского (о. Итуруп, Южные Курильские острова) в 2025 г. Геосистемы переходных зон, 2025, т. 9, № 4, с. 478–484.
https://doi.org/10.30730/gtrz.2025.9.4.478-484, https://www.elibrary.ru/scfbav

1. Zharkov R.V. 2014. [Thermal springs of the Southern Kuril Islands ]. Vladivostok: Dal'nauka, 378 p. (In Russ.).

2. Znamensky V.S., Nikitina I.B. 1985. [Hydrotherms of the central part of Iturup Island (Kuril Islands)]. Volcanology and Seismology, 5: 44–65. (In Russ.).

3. Kalacheva E.G., Taran Yu.A., Kotenko T.A., et al. 2022. Ultra acid sulfate chloride waters of Baransky volcano on Iturup Island, Kurils. The composition and output of magmatic and rock-forming components. Journal of Volcanology and Seismology, 16: 349–364. https://doi.org/10.1134/S0742046322050050

4. Rychagov S.N., Glavatskikh S.F., Goncharenko O.P., et al. 1993. [Temperature and geological-geochemical model of the Ocean geothermal deposit (Iturup Island)]. Geology of Ore Deposits, 5: 405–418. (In Russ.).

5. Bragin I.V., Chelnokov G.A., Zharkov R.V., Kharitonova N.A. 2015. Impact of volcanic fluids on water quality, Baransky volcano, Southern Kuriles. J. Water Resource and Hydraulic Engineering, 4(1–4): 111–114. https://doi.org/10.5963/jwrhe0401011

6. Taran Y.A., Kalacheva E.G. 2020. Acid sulfate-chloride volcanic waters. Formation and potential for monitoring of volcanic activity. Journal of Volcanology and Geothermal Research, 405(107036). https://doi.org/10.1016/j.jvolgeores.2020.107036

7. Gorshkov G.S. 1967. [Volcanism of the Kuril island arc ]. Moscow: Nauka, 288 p. (In Russ.).

8. Bindeman I.N. 1997. [Periodic displacement of magmas with cumulates as a mechanism of cyclic evolution of Baransky volcano (Iturup Island, Kuril Islands)]. Geochemistry, 4: 380–390. (In Russ.).

9. Taran Yu.A., Znamensky V.S., Yurova L.M. 1995. [A geochemical model of hydrothermal systems of Baransky volcano (Iturup Island, Kuril Islands)]. Volcanology and Seismology, 4/5: 95–115. (In Russ.).