Open AccessSeismic mode “drumbeats”, caused by the movement of a viscous lava flow during the Kizimen volcano eruption in may-october 2011
Author(s) -
Alexandra Shakirova,
П. П. Фирстов
Publication year - 2019
Publication title -
rossijskij sejsmologičeskij žurnal
Language(s) - English
Resource type - Journals
eISSN - 2782-1609
pISSN - 2686-7907
DOI - 10.35540/2686-7907.2019.1.06
Subject(s) - lava , extrusive , volcano , geology , seismology , dacite , andesite , lava dome , geophysics , volcanic rock
The “drumbeats” mode is a sequence of volcanic earthquakes with similar waveforms (multiplets) that are recorded from tens of minutes to months. As a rule, the “drumbeats” mode accompanies the squeezing of lava blocks on extrusive domes of andesite-dacite volcanoes. Squeezing and movement of a viscous lava flow during an eruption Kizimen volcano in 2010-2013 was accompanied by multiplets with energy classes K<6 (magnitudes < 2.5), which were recorded from tens of minutes to months. Two series of the strongest multiplets were recorded during the four months from May to mid-October 2011. The volcanic earthquakes of multiplets can be attributed to hybrid and long-period. The coordinates of the foci were identified for the most powerful 35 events of two multiplets of “drumbeats” mode and were localized in the frontal part of the lava flow. The location of the volcanic earthquakes hypocenters suggests that they are generated during the motion of a viscous lava flow the volcano slope. The emergence of multiplets, apparently, can be considered as a process of self-oscillations of the relaxation type.