Three of four Plinian eruptions from Ksudach Volcano are among the four largest explosive eruptions in southern Kamchatka during the past 2000 years. The earliest of the eruptions was voluminous and was accompanied by an ignimbrite and the fifth and most recent caldera collapse event at Ksudach. The isopach pattern is consistent with a column height of 23 km. The three more recent and smaller eruptions were from the Shtyubel' Cone, within the fifth caldera. Using isopach and grain size isopleth patterns, column heights ranged from ≥ 10 to 22 km. Although the oldest eruption may have produced a large acidity peak in the Greenland ice, the three Shtyubel' events may not be related to major acid deposition. Thus it is possible that few if any of the uncorrelated acidity peaks of the past 2000 years in Greenland ice cores result from eruptions in southern Kamchatka.

Avachinsky volcano (Kamchatka, Russia) is an active andesite volcano that poses a significant threat to nearby settlements. There is a high probability of it erupting in the near future. A project to create a pilot volcanological research ground for monitoring the state of the volcano and forecasting eruption scenarios is presented.

From August 14 to 26, 2024, a comprehensive expedition of the Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences worked at the Karymsky Volcanic Center (KVC). Research was conducted to restore the hydrochemistry of Karymsky Lake after the catastrophic underwater eruption that occurred in the Academy of Sciences caldera in early January 1996, and a detailed geochemical survey was made of all thermal manifestations in the center. Seismic observations and assessment of the emission of volcanic gas SO2 were carried out, as carried out by the Karymsky volcano, the volume of above-ground CO2 degassing was measured at the thermal sites of the Karymskaya and Academy of Sciences calderas, and samples of spring water were taken to determine the chemical composition and analyze trace elements. Infrared survey and aerial photography of the southern sector of the KVC were carried out.
This publication presents the first results of seismic observations in conjunction with an assessment of the emission of the SO2 volcanic gas, information on the chemical and mineral composition of the springs of the Karymskaya caldera, and aerial photography data of the volcano.

From August 14 to 26, 2024, a comprehensive expedition of the Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences worked at the Karymsky Volcanic Center (KVC). Research was conducted to restore the hydrochemistry of Karymsky Lake after the catastrophic underwater eruption that occurred in the Academy of Sciences caldera in early January 1996, and a detailed geochemical survey was made of all thermal manifestations in the center. Seismic observations and assessment of the emission of volcanic gas SO2 were carried out, as carried out by the Karymsky volcano, the volume of above-ground CO2 degassing was measured at the thermal sites of the Karymskaya and Academy of Sciences calderas, and samples of spring water were taken to determine the chemical composition and analyze trace elements. Infrared survey and aerial photography of the southern sector of the KVC were carried out.
This publication presents the first results of seismic observations in conjunction with an assessment of the emission of the SO2 volcanic gas, information on the chemical and mineral composition of the springs of the Karymskaya caldera, and aerial photography data of the volcano.