Mount Eniwa

Mount Eniwa
Mount Eniwa
恵庭岳
	From Lake Shikotsu, March 2007
Highest point
Elevation	1,320 m (4,330 ft)
Listing	List of mountains and hills of Japan by height
Coordinates	42°47′36″N 141°17′8″E / 42.79333°N 141.28556°E
Geography
	Mount Eniwa Hokkaidō, Japan Mount Eniwa Mount Eniwa (Hokkaido)
Parent range	Nasu Volcanic Zone
Topo map	Geographical Survey Institute (国土地理院, Kokudochiriin) 25000:1 恵庭岳, 50000:1 樽前山
Geology
Age of rock	Holocene
Mountain type	Stratovolcano
Volcanic arc/belt	Northeastern Japan Arc
Last eruption	1707 ± 30
Climbing
Easiest route	Hike

Mount Eniwa (恵庭岳, Eniwa-dake) is an active^[3] volcano located in Shikotsu-Toya National Park in Hokkaidō, Japan. It sits opposite Mount Tarumae and Mount Fuppushi on the shores of Lake Shikotsu, the caldera lake that spawned the volcanoes. Mount Eniwa is the tallest of the three volcanoes.

Eruptions

The last eruption occurred around the start of the 18th century (c. 1700 ±30 years). There are no historical records of this, but tephrochronology indicates phreatic explosions with mudflows from crater 3. Two centuries before this eruption (c. 1550 ±75 years), radiocarbon dating indicates a similar eruption from crater 2. Around the same time (c. 1500 ±150 years), radiocarbon dating indicates another eruption, but from crater 1. This eruption included debris avalanches instead of mudflows. The oldest eruption that has been dated is an explosive eruption from the east side of the summit around 100 BCE ± 100 years according to radiocarbon dating. All these events were central vent eruptions with a volcanic explosivity index (VEI) of 2.^[2]

Climbing Route

A single trail climbs the eastern side of the mountain. It gets progressively steeper as you climb. The trail starts in a forest about one 1 kilometre (0.6 mi) from Poropinai. The treeline is at about 800 metres (2,600 ft). From there the terrain is rocky and alpine. The climb takes 3-3.5 hours.^[4]^[5]

1972 Winter Olympics

At the 1972 Winter Olympics, Mount Eniwa was the site of the men's and women's downhill ski races.^[6] The course started at the summit and finished on the southwest slope.^[7] The technical events of giant slalom and slalom were held at Teine.

Notes

^ Geological Survey of Japan website Archived 2007-05-26 at archive.today data from ASTER
^ ^a ^b "Shikotsu: Eruptive History". Global Volcanism Program. Smithsonian Institution. Retrieved 2008-04-24.
^ Paul Hunt, Hiking in Japan: An Adventurer's Guide to the Mountain Trails, pg. 179
^ Paul Hunt, Hiking in Japan: An Adventurer's Guide to the Mountain Trails, pg. 181
^ Robert Storey, North-East Asia on a Shoestring, pg. 327
^ "SHIKOTSU-KO". World Lakes Database. International Lake Environment Committee. Archived from the original on 2009-04-16. Retrieved 2008-12-02.
^ 1972 Winter Olympics official report. pp. 281-4.