RECOGNITION OF EARTHQUAKE-PRONE AREAS. XVII\@. MOUNTAIN BELT OF SOUTH AMERICAN ANDESM. B. Filimonov, A. G. Tumarkin and M. P. Zhidkov
We study the Andean mountain belt in South America where locations of possible $M\geq 7.0$ earthquakes are to be identified. Such locations were looked for among intersections of axes of morphostructural lineaments found from morphostructural zonation of the Andes. The $M\geq 7.0$ earthquake epicenters are situated close to some lineament intersections. The task was to recognize the intersections, near which $M\geq 7.0$ events are possible. The classification sought was obtained by the Cora-3 recognition algorithm from geomorphic and morphostructural parameters of the intersections. The parameters provide indirect evidence of the intensity and gradient of tectonic movements and of crustal fragmentation. As a result of recognition, 89 intersections out of a total of 146 were identified as having potential for $M\geq 7.0$ earthquakes. All known earthquakes of this size are confined to the intersections thus recognized. Control tests have been carried out to confirm these results as stable and significant. According to the recognition results, the intersections having potential for $M\ge 7.0$ earthquakes involve high gradients of neotectonic movements and increased crustal fragmentation. The results can be used for earthquake hazard assessment for the Andes.