Mudflows represent one of the major natural hazards affecting river basins of the Greater Caucasus, where their dynamics are controlled by the interaction of hydrometeorological conditions, basin characteristics, sediment availability, and anthropogenic pressures. This study investigates the dynamics of mudflow events in the Azerbaijani part of the Greater Caucasus and develops a classification framework for evaluating their potential hazard. The analysis was based on hydrometeorological records and long-term monitoring materials, with particular attention to rainfall intensity and direction, spatial coverage of river basins, and mudflow characteristics. The results indicate that the spatial progression of intense rainfall plays an important role in the development of catastrophic mudflows. Rainfall progressing from the upper mountainous parts of a basin toward the downstream reaches creates particularly favorable conditions for the formation of high-magnitude mudflows, whereas rainfall of comparable intensity progressing in the opposite direction does not necessarily produce catastrophic events. Based on the combined characteristics of rainfall and basin coverage, mudflows were classified into seven groups. The seventh group, in which intense rainfall affects the entire river basin from the high-mountain zone to the lowland reaches, represents the highest hazard level and corresponds to catastrophic mudflow events. The proposed classification provides a basis for differentiating mudflow hazards and may support the selection of appropriate engineering and risk-reduction measures in vulnerable river basins of the Greater Caucasus.

Keywords: mudflow, sediment transport, intense rainfall, river basin, natural hazards, Greater Caucasus, mudflow classification

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