The Sheveluch volcano is the most active volcano in Kamchatka. The paroxysmal explosive eruption of the volcano that destroyed the lava dome in the volcanic crater continued on April 10–13, 2023. According to various satellite data, the height of the separate eruptive clouds probably exceeded 15 km above sea level. A powerful cyclone, which dominated the entire Kamchatka Peninsula, pulled the eruptive cloud to the west, turned it to the south, stretched it to the north, and directed it to the east from the volcano. The dynamics of the development of ash and aerosol clouds of this eruption is reflected in the animations made from a series of Himawari-9 satellite images in the VolSatView IS from 08:00 UTC on April 10 to 07:00 UTC on April 14 (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683110898.webm) and of the Arctica-M1 satellite from 16:00 to 21:30 UTC on April 10 (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683821166.webm). It was noted that the eruptive column was not vertical: for example, at the initial moment of the eruption on April 10 at 13:20 UTC, it deviated to the north–northeast; on April 11, at 12:00 UTC to the northwest; and, on April 12, at 7:00 UTC to the southwest. During the paroxysmal eruption, sulfur dioxide continuously entered the atmosphere, the maximum amount of which was released on April 10–11, as a result of the explosive destruction of the lava dome of the Sheveluch volcano. Ash clouds along with aerosol clouds on April 10–13 were stretched into a strip more than 3500 km long from west to northeast. On April 21–22, the Sheveluch aerosol cloud was observed in the region of the Scandinavian Peninsula. The total area of the territory of Kamchatka and the Pacific Ocean where ash and aerosol plumes and clouds were observed during the April 10–13 eruption was about 3280000 km2. The paroxysmal eruption of Sheveluch volcano belongs to the sub-Plinian type because it is characterized by a large height of the eruptive cloud and a long event duration. For this eruption, the Volcanic Explosivity Index is estimated to be 3–4. A detailed description of the paroxysmal explosive eruption of the Sheveluch volcano and the spread of the eruptive cloud was performed based on data from various satellite systems (Himawari-9, NOAA-18/19, GOES-18, Terra, Aqua, JPSS-1, Suomi NPP, Arctica-M1, etc.) in the information system “Remote Monitoring of Kamchatka and Kuril Islands Volcanic Activity” (VolSatView, http://kamchatka.volcanoes.smislab.ru).

The powerful explosive eruptions with large volumes of volcanic ash pose a great danger to the population and jet aircraft. Global experience in monitoring volcanoes and observing changes in the parameters of their thermal anomalies is successfully used to analyze the activity of volcanoes and predict their danger to the population. The Kamchatka Peninsula in Russia, with its 30 active volcanoes, is one of the most volcanically active regions in the world. The article considers the thermal activity in 2015–2022 of the Klyuchevskoy, Sheveluch, Bezymianny, and Karymsky volcanoes, whose rock composition varies from basaltic andesite to dacite. This study is based on the analysis of the Value of Temperature Difference between the thermal Anomaly and the Background (the VTDAB), obtained by manual processing of the AVHRR, MODIS, VIIRS, and MSU-MR satellite data in the VolSatView information system. Based on the VTDAB data, the following “background activity of the volcanoes” was determined: 20 °C for Sheveluch and Bezymianny, 12 °C for Klyuchevskoy, and 13–15 °C for Karymsky. This study showed that the highest temperature of the thermal anomaly corresponds to the juvenile magmatic material that arrived on the earth’s surface. The highest VTDAB is different for each volcano; it depends on the composition of the eruptive products produced by the volcano and on the character of an eruption. A joint analysis of the dynamics of the eruption of each volcano and changes in its thermal activity made it possible to determine the range of the VTDAB for different phases of a volcanic eruption.

One of the most important tasks when studying volcanic activity is to monitor their thermal radiation. To fix and assess the evolution of thermal anomalies in areas of volcanoes, specialized hardware-thermal imagers are usually used, as well as specialized instruments of modern satellite systems. The data obtained with their help contain information that makes it relatively easy to track changes in temperature and the size of a thermal anomaly. At the same time, due to the high cost of such complexes and other limitations, thermal imagers sometimes cannot be used to solve scientific problems related to the study of volcanoes. In the current paper, day/night video cameras with an infrared-cut filter are considered as an alternative to specialized tools for monitoring volcanoes’ thermal activity. In the daytime, a camera operated in the visible range, and at night the filter was removed, increasing the camera’s light sensitivity by allowing near-infrared light to hit the sensor. In that mode, a visible thermal anomaly could be registered on images, as well as other bright glows, flares, and other artifacts. The purpose of this study is to detect thermal anomalies on night images, separate them from other bright areas, and find their characteristics, which could be used for volcano activity monitoring. Using the image archive of the Sheveluch volcano as an example, this article presents the results of developing a computer algorithm that makes it possible to find and classify thermal anomalies on video frames with an accuracy of 98%. The test results are presented, along with their validation based on thermal activity data obtained from satellite systems.

This is the first petrophysical study of extrusive rocks (dacites to andesites) discharged by Bezymianny Volcano. We provide a comparative description of properties for extrusive rocks in accordance with identified age groups. We show the dynamics in the variation of extrusive rock properties in relation to their ages, with the result that the older a rock the higher are its density, strength, and elastic parameters. Rocks petrophysical features are compared between extrusive domes and lava flows. We argue for petrophysical properties to be applicable for deriving more accurate results for the genesis of rocks having similar petrophysical properties, in particular, rocks of extrusive and effusive origin.

Сорокин А.А. (4), Королев С.П. (4)

Представлен анализ термальной активности вулканов Камчатки и Курильских островов в 2021-2022 гг. на основе обработки данных ежедневного спутникового мониторинга, проводимого с использованием информационной системы «Дистанционный мониторинг активности вулканов Камчатки и Курильских островов (VolSatView)».

Based on the processing of data from daily satellite monitoring carried out using the information system "Remote monitoring of the activity of volcanoes in Kamchatka and the Kuril Islands (VolSatView)", an analysis of the 2021-2022 thermal activity of Kamchatka and the Kuril Islands volcanoes is presented.

Шивелуч — наиболее активный вулкан Камчатки. Пароксизмальное эксплозивное извержение вулкана, разрушившее лавовый купол в кратере, происходило 10–13 апреля 2023 г. Согласно различным спутниковым данным, высота подъёма отдельных эруптивных облаков, вероятно, превышала 15 км над уровнем моря. Мощный циклон, во власти которого находился весь п-ов Камчатка, вытягивал эруптивное облако на запад, поворачивал его на юг, растягивал на север и направлял на восток от вулкана. Динамика развития пепловых и аэрозольных облаков этого извержения отражена на анимационных картинах, выполненных по сериям снимков спутника Himawari-9 в информационной системе «Дистанционный мониторинг активности вулканов Камчатки и Курил» (ИС VolSatView) с 08:00 UTC (англ. Coordinated Universal Time, всемирное координированное время) 10 апреля до 07:50 UTC 14 апреля (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683110898.webm) и данных спутника «Арктика-М» № 1 с 16:00 до 21:30 UTC 10 апреля (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683821166.webm). Отмечено, что эруптивная колонна во время извержения не была вертикальной: например, в начальный момент извержения 10 апреля в 13:20 UTC она отклонялась на северо-северо-восток, 11 апреля в 12:00 UTC — на северо-запад, 12 апреля в 07:00 UTC — на юго-запад. Во время пароксизмального извержения в атмосферу постоянно поступал диоксид серы, максимальное количество которого выделилось 10–11 апреля, связано это с эксплозивным разрушением лавового купола влк. Шивелуч. Пепловые облака вместе с аэрозольными 10–13 апреля были растянуты в полосу длиной более 3500 км с запада на северо-восток. 21–22 апреля аэрозольное облако Шивелуча отмечалось в районе Скандинавского п-ова. Общая площадь территории Камчатки и Тихого океана, на которой были зарегистрированы пепловые и аэрозольные шлейфы и облака в течение извержения 10–13 апреля, составляла около 3280 тыс. км2. Пароксизмальное извержение Шивелуча относится к субплинианскому типу, так как имеет высокие параметры подъёма пепловых облаков и продолжительности события. Для этого извержения VEI (англ. Volcanic Explosivity Index — вулканический эксплозивный индекс) оценивается как 3–4. Детальное описание пароксизмального эксплозивного извержения вулкана и распространения пеплового облака было выполнено на основании изучения данных различных спутниковых систем (Himawari-9, NOAA-18/19, GOES-18, Terra, Aqua, JPSS-1, Suomi NPP, «Арктика-М» № 1 и др.) в ИС VolSatView (http://kamchatka.volcanoes.smislab.ru).

Sheveluch volcano is the most active volcano in Kamchatka. The paroxysmal explosive eruption of the volcano that destroyed the lava dome in the volcanic crater continued on April 10–13, 2023. According to various satellite data, the height of the separate eruptive clouds probably exceeded 15 km a. s. l. A powerful cyclone, which dominated the entire Kamchatka Peninsula, pulled the eruptive cloud to the west, turned it to the south, stretched it to the north and directed it to the east from the volcano. The dynamics of the development of ash and aerosol clouds of this eruption is reflected in the animations made from a series of Himawari-9 satellite images in the VolSatView IS from 08:00 UTC (Coordinated Universal Time) on April 10 to 07:50 UTC on April 14 (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683110898.webm) and of the Arctica-M1 satellite from 16:00 to 21:30 UTC April 10 (http://d33.infospace.ru/jr_d33/materials/2023v20n2/283-291/1683821166.webm). It was noted that the eruptive column was not vertical: for example, at the initial moment of the eruption on April 10 at 13:20 UTC, it deviated to the north-northeast, on April 11 at 12:00 UTC to the northwest, and on April 12 at 07:00 UTC to the southwest. During the paroxysmal eruption, sulfur dioxide continuously entered the atmosphere, the maximum amount of which was released on April 10–11, as a result of the explosive destruction of the lava dome of the Sheveluch volcano. Ash clouds along with aerosol clouds on April 10–13 were stretched into a strip more than 3500 km long from west to northeast. On April 21–22, the Sheveluch aerosol cloud was observed in the region of the Scandinavian Peninsula. The total area of the territory of Kamchatka and the Pacific Ocean where ash and aerosol plumes and clouds were observed during the April 10–13 eruption was about 3280 thousand km2. The paroxysmal eruption of Sheveluch volcano belongs to the sub-Plinian type because it is characterized by a big height of eruptive cloud and a long event duration. For this eruption, the VEI (Volcanic Explosivity Index) is estimated to be 3–4. A detailed description of the paroxysmal explosive eruption of Sheveluch volcano and the spread of the eruptive cloud was performed based on data from various satellite systems (Himawari-9, NOAA-18/19, GOES-18, Terra, Aqua, JPSS-1, Suomi NPP, Arctica-M1 etc.) in the information system “Remote monitoring of the activity of the volcanoes of the Kamchatka and the Kuriles” (VolSatView, http://kamchatka.volcanoes.smislab.ru).

В работе описана активность вулкана Безымянный в 2022 г. Произошло три пароксизмальных эксплозивных извержения вулкана в марте, мае и октябре, они представляли опасность для международных и местных авиаперевозок.

На основе методов компьютерного зрения и машинного обучения разработаны алгоритмы для классификации снимков со стационарных видеокамер, а также детектирования на них признаков активности вулкана. Приведены результаты апробации разработанных алгоритмов на примере данных наблюдения за вулканами Ключевской и Шивелуч. Показано, что предложенные решения могут использоваться для оперативного мониторинга и ретроспективного анализа вулканической активности.

Based on computer vision and machine learning methods, algorithms have been developed to classify images from fixed video cameras, as well as detect signs of volcanic activity in them. The results of testing the developed algorithms are presented using the example of observation data on the Klyuchevskoy and Sheveluch volcanoes. It is shown that the proposed solutions can be used for operational and retrospective monitoring of volcanic activity.

Впервые представлены результаты петрофизических исследований экструзивных пород вулкана Безымянный от дацитов до андезитов. Приведена сравнительная характеристика свойств пород экструзий согласно выделенным возрастным группам. Показана динамика изменения свойств пород экструзий в зависимости от их возраста: установлено, что чем древнее породы, тем выше показатели их плотностных, прочностных и упругих свойств. Проведено сопоставление петрофизических особенностей пород экструзивных куполов и лавовых потоков. Обоснована применимость петрофизических свойств для уточнения генезиса сходных по петрографическим характеристикам пород, в частности, экструзивного и эффузивного происхождения.

This is the first petrophysical study of extrusive rocks (dacites to andesites) discharged by Bezymianny Volcano. We provide a comparative description of properties for extrusive rocks in accordance with identified age groups. We show the dynamics in the variation of extrusive rock properties in relation to their ages, with the result that the older a rock the higher are its density, strength, and elastic parameters. Rocks petrophysical features are compared between extrusive domes and lava flows. We argue for petrophysical properties to be applicable for deriving more accurate results for the genesis of rocks having similar petrophysical properties, in particular, rocks of extrusive and effusive origin.