S44B-01
Volcanic activity observed from continuous seismic records in the region of the Klyuchevskoy group of volcanoes
Thursday, 17 December 2015: 16:00
307 (Moscone South)
Nikolai Shapiro1,2, Dmitry Droznin3, Svetlana Droznina3, Sergey Senyukov3, Victor Chebrov3, Evgenii Gordeev2 and William Frank1, (1)Institut de Physique du Globe de Paris, Paris, France, (2)Institute of Volcanology and Seismology, Petropavlovsk Kamchatsky, Russia, (3)Kamchatkan Branch of the Russian Geophysical Survey, Petropavlovsk Kamchatsky, Russia
Abstract:
We analyze continuous seismic records from 18 permanent stations operated in vicinity of the Klyuchevskoy group of volcanos (Kamchatka, Russia) during the period between 2009 and 2014. We explore the stability of the inter-station cross-correlation to detect different periods of sustained emission from seismic energy. The main idea of this approach is that cross-correlation waveforms computed from a wavefield emitted by a seismic source from a fixed position remain stable during the period when this source is acting. The detected periods of seismic emission correspond to different episodes of activity of volcanoes: Klyuchevskoy, Tolbachik, Shiveluch, and Kizimen. For Klyuchevskoy and Tolbachik whose recent eruptions are mostly effusive, the detected seismic signals correspond to typical volcanic tremor, likely caused by degassing processes. For Shiveluch and Kizimen producing more silicic lavas, the observed seismic emission often consists of many repetitive long period (LP) seismic events that might be related to the extrusion of viscous magmas. We develop an approach for automatic detection of these individual LP events in order to characterize variations of their size and recurrence in time.
