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Abstract
Intensity of the Muya, 1957 earthquake is assessed in localities based on macroseismic data and in epicentral area based on effects in natural environment; it is analyzed how these assessments correspond to each other and to instrumental location of epicenter, hypocentral depth, and magnitude; it is evaluated, how seismodislocations of the Muya earthquake could serve as control of palaeoseismostructure parameters in this region. Spatial distribution of macroseismic effect confirms relatively deep source (20-22 km). Deep source agrees with anomalously short surface rupture length (not more than 25 km); only a part of the source exposed on the surface. Comparison with length of palaeoseismostructures shows that it is a regional feature. Epicentral intensity based on surface ruptures is assed X degrees in ESI2007 scale. Ignoring geological effects will underestimate epicentral intensity up to two degrees. Source mechanism with three sub-sources is in agreement with segmentation of surface ruptures. Sub-sources are of strike-slip type with small normal component; essential normal slip at surface is probably not representative for the source and is due to accommodation of strike-slip movement along with a system of sub-parallel en echelon ruptures under tension.[PUBLICATION ABSTRACT]





