by Gennady KARPOV, Dr. Sc. (Geol. & Mineral.), Deputy Director of the RAS SB Institute of Volcanology and Seismology (Petropavlovsk-Kamchatsky)
Vulcanism is often an unexpected, catastrophic and in many respects unexplored natural phenomenon driven by powerful physico-chemical and dynamic processes in terrestrial depths. Volcanic eruptions bring an in-depth gaseous, liquid, and solid element to the surface. It is important to study it to accumulate knowledge about the inner spheres of the planet and extend practical applications-for ore geology, volcanology, and many related disciplines such as seismology, climatology, and ecology. Despite of significant volumes of lava products that change the relief and build up the earth crust, it is well known that minute particles brought out into the atmosphere-ashes and aerosols (by estimate, about 100 mln tons of volcanic ashes get to the atmosphere) have major impact on the atmosphere, while powerful catastrophic eruptions can even change the climate of the Earth in general. Spread by the wind for hundreds of kilometers, ashes pose a great threat to air traffic. They also stimulate accumulation of loose material in soils and water bodies. In this context, it is very important to study material and mineral composition of ashes, which is a subject of the present article.
Regular eruptions are accompanied by ejection of 5,000 t of crushed and finely crushed volcanic material per one second. Major and catastrophic eruptions bring out even more. For example, in the culmination point of eruption of Bezymianny volcano in the Kamchatka Peninsula on March 30, 1956, about 150 mln t of ashes were ejected. According to the data obtained by Nikolai Zharinov, Cand. Sc. (Tech.), and Yuri Demyanchuk, employees of the RAS SB Institute of Volcanology and Seismology, for the period from 1955 to 2009, only this very volcano ejected about 918.5 mln t of ashes. During the intense explosion of Karym-sky volcano on ... Читать далее