41.80 N, 140.68 E
summit elevation 618 m
E-san is the southern most active volcano in Hokkaido.
Fumaroles are located on the upper NW flank.
Hot Springs at E-san volcano
1) Hot and tepid springs are divided into two groups by the boundary along the River Yaziri.
2) Mizunashi hot spring is artesian with porous aquifer of liparitic andésite.
3) The Mizunashi hot spring region has different structures between the southern and the northern parts. Hot spring of the southern part is more active than the northern one.
4) The maximum temperature of hot springs is 52.4°C at a coastal location.
5) Influence of sea water on the nature of spring water was little or none so far as the chemical composition of spring water at low tide is concerned.
6) Temperatures of hot water which exceed 47°C was observed under the ground down to 35 m depth from sea level. The maximum temperature among the observed points was measured at a depth of 32 m, 294 cm from the head in the test boring well, at the distance of 50 m from the Mizunashi coast.
7) The source of the Mizunashi hot spring is located in the direction of East, Esan Volcano.
A phreatic eruption occurred at E-san volcano on 18th November 1846, causing the deaths of three people.
1874, 1846, 3900 BC ± 100 yr.