Inferences on Mixed Snow Avalanches from Field Observations

摘要: Observations of the deposits, flow marks, and damages three mixed-snow avalanches widely different size were analyzed with regard to regimes, velocities, pressures, densities, depths, erosion modes, mass balance. Three deposit types density granulometry could be clearly discerned in these avalanches. They are attributed dense, fluidized, suspension respectively. Combining observations, we estimated fluidized layer as 35–100 kg m − 3 , good agreement inferences from pressure measurements. Upper bounds for density, arising run-up height, velocity, damage pattern, about 5 at valley bottom. An approximate momentum balance dense suggests that snow cover was eroded considerable depth, but only partly entrained into proper. The had largely lost its erosive power point where it separated denser parts avalanche. Our estimates shed doubt on collisions between particles aerodynamic forces head avalanche sole mechanisms creating upholding layer. We conjecture drag air escaping is being compressed by overriding supply missing lift force.