Novye Issledovaniâ Tuvy (Mar 2017)
Seismic history of the Altai-Sayan region and the 2011-2012 earthquakes in Tuva
Abstract
The Tuva earthquakes of 2011-2012, being the strongest in the history of seismic study in Tuva, attracted the attention of professionals and became the first well-studied seismic events in Tuva. The paper provides a general overview of seismic history of the Altai-Sayan region and a look at a particular seismogenic structure – the Kaakhem system of active faults), where the 2011-2012 earthquakes occurred. A reconstruction of the seismic history of Tuva can follow a number of paths – aside from paleoseismological methods, those of archeoseismology and historical seismology can be quite helpful. Legends and more specific information on ancient constructions’ collapse can provide some useful information on earthquake dates, as well as earth tremor mapping. To locate seismic foci of the earthquakes of the past and assess their parameters, we may recourse to dating their geological vestiges, written evidence and archaeoseismological study outcomes obtained by means of velocity destruction indicators set in ancient buildings. Our comparative analysis has shown that the events of 2011-2012 are "ordinary" events against the background of the most powerful seismic catastrophes of the 20th century in the Altai-Sayan region, as well as prehistoric palaeoearthquakes located in the Kaakhem fault zone.
