Results of complex study of pyroclastic deposits from Bezymianny and Schiveluch volcanoes are present in this work. Comparative characteristics of engineering-geological features are given for various genetic types of pyroclastic deposits from andesitic volcanoes, as well as for pyroclastic deposits from andesitic and basaltic volcanoes on the whole.
Criteria for distinguishing genetic types of pyroclastic deposits from andesitic volcanoes have been substantiated.

The Klyuchevskaya volcanic group of Kamchatka is unique in many respects: it includes 13 volcanoes, four of which are active; Klyuchevskoy volcano is the youngest and the most active of Kamchatka; the contrast (basaltic and andesitic) volcanism is observed within the relatively small area of this group. This work provides a general scheme of principal fault zones in the area of the Klyuchevskaya volcanic group superimposed on satellite data of middle and high resolution (MODIS, SRTM, ASTER, Landsat, Meteor-M, Kanopus-B and the others). The scheme of the fault zones was created on the basis of the analysis of a set of various published materials and numerous satellite data of different resolution, as well as on the author’s studies of the Klyuchevskaya group volcanoes. All faults at the scheme were well expressed in all examined satellite images. It is shown that the faults ever formed here are long-lived and their activity is associated with certain stages of the evolution of the Klyuchevskaya volcanic group. The formation of all volcanoes of this group mainly happens owing to faults of the northwest, northeast and west-northwest directions. For example, the current activity of Klyuchevskoy volcano is associated probably with the northwest and northeast striking faults; right-hand downthrow-upheaval movements along the faults of the north-northeast directions are likely to have led at different times to the collapse of the eastern parts of the volcanoes Ostry Tolbachik and Kamen.