Slush
avalanche event in Mount Fuji has most frequently occurred in the southeastern slope as well as Kengamine Osawa valley (Osawa-kuzure). Asymmetric vegetation and landscape between the southeast slope and the other side are caused by not only direct impact from the 1707 Hoei eruption but also succeeding such slash events. During from late 2006 to the 2009, seven
slush
events were ascertained. These event started from the approximately same dried-up shallow valleys as scoria mixed
slush
avalanche and subsequent mud flow. Fresh sedimentary and eroded topography were formed by these events, at the middle and lower part of the shallow valleys. Aerial photographs show that similar valley heads have existed at the same location at least past 60 years. Thus, volume of aggradation and erosion within these valleys are equal in quantity owing to repeated
slush
events. Passing the well-developed low pressure system in Japan sea were observed in every
slush
event in common with previous studies. Difference of sea level pressure between the northwestern and southeastern side of middle part of the Honshu island can reveal such atmospheric pressure distribution. Furthermore, air temperatures approximately -5 2C at the summit and +13 2C at
Gotemba, and precipitation approximately 10 mm/hour at Inno and Akatsuka can be considered as the meteorological threshold for occurrence of
slush
avalanche in the southeastern slope. Hence, these obvious tendencies and thresholds of the meteorological elements may allow the establishment of a objective criteria for disaster prediction for
slush
avalanche. For the further verification of occurrence condition, it is necessary to observe the extent of the minor
slush
events and obtain the meteorological data in the all direction of flank of Mount Fuji.
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