Recognition of strong (М ≥ 6½) earthquake-prone areas in California has been performed using the modified version (FCAZm) of the original algorithmic system FCAZ (Formalized Clustering And Zoning). This system is the part of the Discrete Mathematical Analysis (DMA) – the original approach towards analysis of geological and geophysical discrete data, which was developed in the Geophysical Center of RAS. The recognition objects used by the system are represented solely by information on the earthquake epicenters. For the territory of California, the earthquake epicenters with M ≥ 3.0 were selected. Highly-seismic FCAZm-zones, recognized in California, agree well with the location of earthquake epicenters with М ≥ 6½. The epicenters of practically all strong earthquakes fall within the FCAZm-zones. The veracity of the recognized zones was confirmed by results of the control experiments «individual seismic history» and «complete seismic history». The FCAZm-zones have been compared with the ones earlier recognized by the classical EPA-method (1976) and by the initial version of the FCAZ system (2014). It was revealed that within California the area of the FCAZm-zones is twice smaller than the area of the EPA-zones. In addition, the FCAZm-zones better agree with the М ≥ 6½-earthquake epicenters than the EPA-zones. The results of this research allow to suggest the high veracity of the interpretation of FCAZm-zones as the strong earthquake-prone areas in California. The FCAZm-zones agree well with the classical EPA-zones and improve them, and make them clearer

Dzeboev Boris, PhD, Geophysical Center of the Russian Academy of Sciences, Senior research scientist, Geophysical Institute of Vladikavkaz Scientific Center of the Russian Academy of Sciences, Research scientist. 119296, Moscow, ul. Molodezhnaya, 3. E-mail: b.dzeboev@gcras.ru.

Krasnoperov Roman, PhD, Geophysical Center of the Russian Academy of Sciences, Senior research scientist. 119296, Moscow, ul. Molodezhnaya, 3. E-mail: r.krasnoperov@gсras.ru.

Belov Ivan, Geophysical Center of the Russian Academy of Sciences, Junior research scientist. 119296, Moscow, ul. Molodezhnaya, 3. E-mail: i.belov@gcras.ru.

Barykina Yuliya, Geophysical Center of the Russian Academy of Sciences, Junior research scientist. 119296, Moscow, ul. Molodezhnaya, 3. E-mail: u.barykina@gcras.ru.Center of the Russian Academy of Sciences, Junior research scientist. E-mail: u.barykina@gcras.ru

Vavilin Evgeniy, Geophysical Center of the Russian Academy of Sciences, Junior research scientist. 119296, Moscow, ul. Molodezhnaya, 3. E-mail: e.vavilin@gcras.ru.

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