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Assumed scale and effects of a eruption represented in this map.

This map covers areas at risk from lava flows, volcanic bomb and lapilli fallouts , pyroclastic flows, and mudflows from melting snow. Other dangers, such as volcanic ash, are likely to occur as well.

About Volcanic Ash.

  • If Mt. Fuji erupts, volcanic ash may fall over a large area.
  • Volcanic ash piles up thickly at the source of the eruption and thins out as the distance from the crater grows. However, volcanic ash distribution changes greatly depending on wind direction, speed, and size of the eruption.
  • Volcanic ash may cause health problems, damaged crops, disrupted traffic, electrical outages, and building collapse as it accumulates.
  • Volcanic ash creates a condition where mudflows develop easily during rainfall.

Assumed Scale of an Eruption.

  • Evacuation in advance of a large scale eruption is possible thanks to the detection of precursor volcanic activity.
  • In the event of a small scale eruption, precursor volcanic activity may be overlooked; however, in this case the threat of damage to towns at the foot of the volcano is low.
  • This map represents 3 distinct zones affected by an eruption. Depending on the scale of the eruption, only the zone where the crater develops will be affected, and not the entire map. Please read further for more information.

Data on Past Mt. Fuji Eruptions.

Large Scale. 2% (A.D.864 Jogan Eruption. A.D.1707 Houei Eruption)
Mid Scale. 11% (Kenmarubi Flow. Innomarubi Flow)
Small Scale. 87%


Follow the information provided by local authorities, and be prepared for an early evacuation!