Аннотация:We report an attempt to reconstruct slushflow activity, evaluate its contribution into sediment budgets and impact on geomorphic structure and fluvial processes in the Khibiny Mountains valleys by means of detailed description of associated landforms and correlated deposits analyses (structural, grainsize, radionuclide fingerprinting, 14C dating). Slushflow represent a specific type of gravitational flow of water-saturated mixture of snow with limited amount of clastic material. Available results for the studied basins suggest slushflows as a leading mechanism of downstream sediment delivery and valley floor transformation in Holocene. Recurrence interval of medium-magnitude slushflows does not exceed 10-30 years, though fluvial topography is suppressed or almost nonexistent as streams are unable to rework slushflow deposits. Frequency of extreme events is much lower. Nevertheless, largest-scale bottom features and piedmont fans can be related to much more intense events associated with last deglaciation stages.
