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Show k the snow pack for extremely long periods of time. It defies metamorphism and tends to freeze into crust layers. It often creates air pockets either underneath or internally. These graupel layers, loose or crusted, often hold the key to determining depth of possible fractures, and are second only to the old snow surface as a contributing slide surface. Powder snow, such as associated with powder skiing, has not been common at Mt. Baldy recently. However, with sufficient depth ( 24' plus), snow with densities up to 0.09 has provided satisfactory " powder skiing." The highest densities recorded have been new snow in the form of larcje crystals. SNOW METAMORPHISM Two factors deserve notice in relation to metamorphism in our show pack. The first of- these is the effect, of erratic temperature fluctuations. For example: Late March, or even April in the last three years have brought our deepest new snow deposits. Temperature prior, and immediately after these storms, which deposit their snow near the freezing point, have ranged near 60 degrees. The second influence is that of the ground temperature itself. More often than not, these late snow packs are deposited on warm ground, particularly of southern or southwestern exposures, such as Hocomoc Canyon. ( See Fig. VI). This can produce several complications, even in comparatively deep packs such as the 5' pack of April 1965, in a matter of days. For example: |