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Hakoneyama

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  • Japan
  • Complex
  • 2015 CE
  •  
  • Country
  • Primary Volcano Type
  • Last Known Eruption
  •  
  • 35.233°N
  • 139.021°E

  • 1438 m
    4718 ft

  • 283020
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number
Most Recent Weekly Report: 2 October-8 October 2019 Citation IconCite this Report

On 7 October JMA lowered the Alert Level for Hakoneyama to 1 (the lowest level on a 5-level scale), noting that the number of volcanic earthquakes had decreased to background levels after a spike in seismicity was recorded in May. Inflation had been detected but had become almost stagnant after late August. Fumaroles in the Owakudani hot springs area continued to be active, with gas-and-steam plumes rising 100-400 m above their vents.

Source: Japan Meteorological Agency (JMA)


Most Recent Bulletin Report: April 2016 (BGVN 41:04) Citation IconCite this Report

Small explosions and new fumaroles in the Owakudani thermal area during June 2015

The Hakoneyama volcano includes large calderas, post-caldera domes, and active thermal areas about 80 km SW of Tokyo. Phreatic explosions have been radiocarbon dated to the 12th or 13th centuries CE, and periodic seismic swarms have been recorded since the late 20th century when regular monitoring began. Renewed activity at the Owakudani hot spring area (1 km N of the Kamiyama dome summit), including two small explosions and the formation of several new fumaroles, was reported by the Japan Meteorological Agency (JMA) in 2015. The area is a popular resort destination with golf courses, spas, skiing, and aerial tramways.

Seismic swarms were previously reported in 1991 (BGVN 16:04), 2001, 2011, and 2013. A slight inflation of the volcanic edifice was recorded between December 2012 and March 2013. Increased seismicity and intense steam emissions at Owakudani were observed beginning in April 2015, and on 29 and 30 June 2015 two small explosions from a new fumarole created a mound of ash around the vent and scattered ash a few hundred meters N. Additional ash was observed in the early morning of 1 July. Strong degassing from the fumaroles continued through the end of the year, although seismicity dropped below detection by mid-August, and inflation stopped at the end of August.

Activity during 1991-2014. A swarm of about 300 earthquakes, all less than M 2.5 and located at 5 km depth below the central part of the caldera, was reported by JMA in April 1991 and felt by area residents (BGVN 16:04). Between June and August 2001 elevated seismicity from depths less than 5 km below the surface was associated with a small amount of inflation centered at the volcano; a small swarm was also recorded under the N end of Ashino-ko (Lake Ashi).

A brief period of increased seismicity was again recorded in the few days following the 11 March 2011 Tohoku Earthquake which was centered about 400 km NE. The activity was confined to the area around the Owakudani hot springs. On 21 March 2011, a M 4.2 earthquake occurred around the Komagatake dome (1 km SSE of Kamiyama). Fumes from the Sounjigoku geothermal area on the E side of the volcano were observed rising 50-200 m during March 2011. The tiltmeter network operated by the Hot Springs Research Institute of Kanagawa Prefecture showed no relevant changes resulting from the earthquake.

Between January and March 2013, JMA reported a slight increase in the number of shallow earthquakes in the area between Komagatake and Sengokuhara Hot Spring (4 km NE of Kamiyama dome). Strainmeter and tiltmeter observations recorded a slight inflation of the volcano that began at the end of 2012 and stopped by the end of February 2013.

Activity during 2015. Scientists conducted field surveys on 4-5 April 2015 and observed forceful steam emissions at the Owakudani hot spring complex that continued at least through 8 April. Six small seismic events were recorded on 10 April in the Yumoto area of the city of Hakone (8 km ESE). JMA reported an increased seismicity to tens of daily events at Hakoneyama beginning 26 April 2015. On 5 May, three more small seismic events were recorded in the Yumoto area. This led JMA to raise the Volcano Alert Level from 1 (Normal) to 2 (Do not approach the crater) on a 5-level scale on 6 May. There were 21 additional small seismic events in the Yumoto area during May 2015. The daily total of all seismic events rose significantly to 442 on 15 May, the highest since 2001.

Ground deformation data showed changes attributable to the seismic events. The Mainichi (a daily newspaper) reported on 17 May 2015 that an analysis of satellite data by the Geospatial Information Authority of Japan found that the ground level in a 200-m-diameter area in the Owakudani district rose 12 cm between 17 April and 15 May. Intense steam emissions continued at the Owakudani hot spring supply complex in May (figure 1).

Figure (see Caption) Figure 1. An aerial photo taken by the Kyodo News helicopter shows steam rising from the Owakudani hot spring supply facility at Hakoneyama on 7 May 2015. Courtesy of The Japan Times.

Volcanic tremor lasting for around five minutes started at 0732 on 29 June 2015. At around 1245, fallout was observed in an area up to 1.2 km N and NE of the Owakudani hot spring complex. This fallout was interpreted by JMA to be sediment and debris ejected from a "blowhole" that formed a new fumarole at Owakudani. A field survey conducted on 30 June observed a mound of volcanic ash around the new fumarole. Additionally, volcanic ash was observed near the Owakudani Station of the Hakone Ropeway (a resort tramway) located about 300 m NNW of the hot springs area. As a result of the discovery of the ashfall, JMA raised the Alert Level at 1230 on 30 June from 2 to 3 (Do not approach the volcano).

Additional volcanic ash was found on a camera around 0500 on 1 July. Air shocks that were intermittently observed from 1600 on 29 June to 1 July may have occurred in association with eruptions, the last occurring between 0400 and 0500 on 1 July. A field survey conducted by the Hot Springs Research Institute of Kangawa Prefecture and JMA on 2 July confirmed continued forceful emissions of steam at the new fumarole, which had grown to 20 m in diameter, and was designated Crater 15-1. Three other new fumaroles were also observed around this crater.

No low-frequency earthquakes or volcanic tremors were recorded in July, but active degassing at Crater 15-1 and adjacent fumaroles continued. In a field survey on 6 August 2015, material described as "dark gray soil" was observed around the fumarole, inside the crater rim. Thermal infrared observation showed a high-temperature area on the E side of the crater from August through October. A single, minor seismic event was recorded on 17 August, the first one since 3 July. JMA downgraded the Alert Level at the volcano from 3 (Do not approach the volcano) to 2 (Do not approach the crater) on 11 September, and no further changes in the tiltmeter or strainmeter data were observed after August.

Field surveys on 3 and 29 September indicated that "dark gray soil" continued to be ejected from Crater 15-1, but the scale of the explosions were small and ejection heights were lower than the crater rim. Strong degassing was still occurring at the crater and all other fumaroles. By 20 November the slight weakening of the emissions from Crater 15-1 and overall stability and low seismic activity led JMA to reduce the Volcanic Alert Level further to 1 (Potential for increased activity). Field observations on 7 and 9 December 2015 confirmed continuing strong degassing with plumes to 600 m in the area around Owakudani, but no new ejecta.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); The Mainichi, Japan's National Daily since 1922 (URL: http://mainichi.jp/english/); The Japan Times (URL: http://www.japantimes.co.jp/news/2015/05/07/national/volcano-alert-raised-mount-hakone/#.WHkqQHrcDy1).

Weekly Reports - Index


2019: May | October
2015: May | June | July | November
2001: August


2 October-8 October 2019 Citation IconCite this Report

On 7 October JMA lowered the Alert Level for Hakoneyama to 1 (the lowest level on a 5-level scale), noting that the number of volcanic earthquakes had decreased to background levels after a spike in seismicity was recorded in May. Inflation had been detected but had become almost stagnant after late August. Fumaroles in the Owakudani hot springs area continued to be active, with gas-and-steam plumes rising 100-400 m above their vents.

Source: Japan Meteorological Agency (JMA)


22 May-28 May 2019 Citation IconCite this Report

JMA reported that the number of earthquakes at Hakoneyama increased on 18 May and remained elevated through 27 May. The epicenters were centered around the W bank of Lake Ashinoko and around Komagatake. Global Navigation Satellite Systems (GNSS) data continued to indicate a trend of inflation. The Alert Level remained at 2 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 May-21 May 2019 Citation IconCite this Report

JMA reported that the number of earthquakes at Hakoneyama increased during 18-19 May, with epicenters centered around the W bank of Lake Ashinoko and around Komagatake. Fumaroles in the Owakudani hot springs area continued to be active. Global Navigation Satellite Systems (GNSS) data showed changes in deformation beginning in mid-March. On 19 May JMA raised the Alert Level to 2 (on a 5-level scale). Elevated seismicity continued to be recorded through 21 May.

Source: Japan Meteorological Agency (JMA)


18 November-24 November 2015 Citation IconCite this Report

According to a news article from 20 November, JMA lowered the Alert Level for Hakoneyama to 1 (on a scale of 1-5) due to continuing low levels of seismicity.

Source: The Japan Times


8 July-14 July 2015 Citation IconCite this Report

On 12 July JMA reported that the webcam continued to record vigorous fumarolic plumes rising from Hakoneyama's Owakudani hot spring area. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 July-7 July 2015 Citation IconCite this Report

According to a news article a drone that surveyed the Owakudani hot spring district at Hakoneyama recorded damage to three hot spring supply facilities; an exclusion zone for visitors was in effect due to increased seismic activity and an Alert Level raise to 2 (on a 5-level scale) on 6 May. At 1230 on 30 June a small-scale eruption occurred and the Alert Level was raised to 3. On 1 July a news article noted another small-scale eruption (occurring between 0400 and 0500), and JMA reported that ash deposits were visible with the webcam. During fieldwork on 2 July, scientists confirmed new fumaroles at Owakudani that were vigorously emitting white plumes; the new fumaroles had formed during 29-30 June. White fumarolic plumes continued to be emitted through 5 July.

Sources: Japan Meteorological Agency (JMA); The Japan Times; The Japan Times


24 June-30 June 2015 Citation IconCite this Report

JMA reported that on 29 June scientists visiting Hakoneyama observed new fumaroles in a landslide-prone area, appearing after a possible landslide had occurred. Fresh sediment deposits within 2 km were possibly caused by the formation of the fumaroles. Seismicity began increasing at 1930, and a 5-minute-period of volcanic tremor began at 1932. At 1230 on 30 June a small-scale eruption occurred. The Alert Level was raised to 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 May-19 May 2015 Citation IconCite this Report

JMA reported that during 14-17 May seismicity at Hakoneyama remained high. Inclinometer data showed variations related to seismicity, and vigorous steaming from the hot springs was observed. The Alert Level remained at 2 (on a 5-level scale). According to a news article, the ground level in the Owakudani hot spring area had risen 12 cm during 17 April-15 May; the deformation occurred in an area 200 m in diameter. The article also noted that 471 earthquakes were recorded on 15 May, the highest number ever recorded there in one day.

Source: Japan Meteorological Agency (JMA)


6 May-12 May 2015 Citation IconCite this Report

On 6 May JMA raised the Alert Level for Hakoneyama from 1 to 2 (on a 5-level scale). Seismicity had increased on 26 April, and on 5 May three events occurred that were Intensity I. Inclinometer data showed variations related to seismicity, and vigorous steaming from the hot springs was observed. Seismicity remained elevated at least through 10 May.

Source: Japan Meteorological Agency (JMA)


8 August-14 August 2001 Citation IconCite this Report

Elevated seismicity had been recorded at Hakone during June 2001 to at least 8 August. The seismicity was associated with a small amount of inflation that was centered at the volcano. Earthquake hypocenters occurred at depths less than 5 km beneath the volcano. A small swarm was also recorded under the northern end of the Ashino-ko (caldera lake). JMA noted that the change in activity might not be a precursor to an eruption since similar activity has occurred in the past that was not followed by an eruption.

Source: Volcano Research Center-Earthquake Research Institute (University of Tokyo)


Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

04/1991 (BGVN 16:04) Brief earthquake swarm in center of caldera

04/2016 (BGVN 41:04) Small explosions and new fumaroles in the Owakudani thermal area during June 2015




Information is preliminary and subject to change. All times are local (unless otherwise noted)


April 1991 (BGVN 16:04) Citation IconCite this Report

Brief earthquake swarm in center of caldera

A swarm of ~300 earthquakes (M <= 2.5) was recorded between 1000 and 1300 on 22 April. Several of the earthquakes, located at 5 km depth in the central part of the caldera, were felt by area residents. Seismicity gradually declined, and had returned to normal by 24 April. No changes in surface activity were observed. Earthquake swarms have been recorded about once a year, including one in August 1990 (M <= 5.1), at the volcano's E foot. Hakone erupted phreatically about 3,000 years ago, and many fumaroles and hot springs remain active.

Information Contacts: JMA.


April 2016 (BGVN 41:04) Citation IconCite this Report

Small explosions and new fumaroles in the Owakudani thermal area during June 2015

The Hakoneyama volcano includes large calderas, post-caldera domes, and active thermal areas about 80 km SW of Tokyo. Phreatic explosions have been radiocarbon dated to the 12th or 13th centuries CE, and periodic seismic swarms have been recorded since the late 20th century when regular monitoring began. Renewed activity at the Owakudani hot spring area (1 km N of the Kamiyama dome summit), including two small explosions and the formation of several new fumaroles, was reported by the Japan Meteorological Agency (JMA) in 2015. The area is a popular resort destination with golf courses, spas, skiing, and aerial tramways.

Seismic swarms were previously reported in 1991 (BGVN 16:04), 2001, 2011, and 2013. A slight inflation of the volcanic edifice was recorded between December 2012 and March 2013. Increased seismicity and intense steam emissions at Owakudani were observed beginning in April 2015, and on 29 and 30 June 2015 two small explosions from a new fumarole created a mound of ash around the vent and scattered ash a few hundred meters N. Additional ash was observed in the early morning of 1 July. Strong degassing from the fumaroles continued through the end of the year, although seismicity dropped below detection by mid-August, and inflation stopped at the end of August.

Activity during 1991-2014. A swarm of about 300 earthquakes, all less than M 2.5 and located at 5 km depth below the central part of the caldera, was reported by JMA in April 1991 and felt by area residents (BGVN 16:04). Between June and August 2001 elevated seismicity from depths less than 5 km below the surface was associated with a small amount of inflation centered at the volcano; a small swarm was also recorded under the N end of Ashino-ko (Lake Ashi).

A brief period of increased seismicity was again recorded in the few days following the 11 March 2011 Tohoku Earthquake which was centered about 400 km NE. The activity was confined to the area around the Owakudani hot springs. On 21 March 2011, a M 4.2 earthquake occurred around the Komagatake dome (1 km SSE of Kamiyama). Fumes from the Sounjigoku geothermal area on the E side of the volcano were observed rising 50-200 m during March 2011. The tiltmeter network operated by the Hot Springs Research Institute of Kanagawa Prefecture showed no relevant changes resulting from the earthquake.

Between January and March 2013, JMA reported a slight increase in the number of shallow earthquakes in the area between Komagatake and Sengokuhara Hot Spring (4 km NE of Kamiyama dome). Strainmeter and tiltmeter observations recorded a slight inflation of the volcano that began at the end of 2012 and stopped by the end of February 2013.

Activity during 2015. Scientists conducted field surveys on 4-5 April 2015 and observed forceful steam emissions at the Owakudani hot spring complex that continued at least through 8 April. Six small seismic events were recorded on 10 April in the Yumoto area of the city of Hakone (8 km ESE). JMA reported an increased seismicity to tens of daily events at Hakoneyama beginning 26 April 2015. On 5 May, three more small seismic events were recorded in the Yumoto area. This led JMA to raise the Volcano Alert Level from 1 (Normal) to 2 (Do not approach the crater) on a 5-level scale on 6 May. There were 21 additional small seismic events in the Yumoto area during May 2015. The daily total of all seismic events rose significantly to 442 on 15 May, the highest since 2001.

Ground deformation data showed changes attributable to the seismic events. The Mainichi (a daily newspaper) reported on 17 May 2015 that an analysis of satellite data by the Geospatial Information Authority of Japan found that the ground level in a 200-m-diameter area in the Owakudani district rose 12 cm between 17 April and 15 May. Intense steam emissions continued at the Owakudani hot spring supply complex in May (figure 1).

Figure (see Caption) Figure 1. An aerial photo taken by the Kyodo News helicopter shows steam rising from the Owakudani hot spring supply facility at Hakoneyama on 7 May 2015. Courtesy of The Japan Times.

Volcanic tremor lasting for around five minutes started at 0732 on 29 June 2015. At around 1245, fallout was observed in an area up to 1.2 km N and NE of the Owakudani hot spring complex. This fallout was interpreted by JMA to be sediment and debris ejected from a "blowhole" that formed a new fumarole at Owakudani. A field survey conducted on 30 June observed a mound of volcanic ash around the new fumarole. Additionally, volcanic ash was observed near the Owakudani Station of the Hakone Ropeway (a resort tramway) located about 300 m NNW of the hot springs area. As a result of the discovery of the ashfall, JMA raised the Alert Level at 1230 on 30 June from 2 to 3 (Do not approach the volcano).

Additional volcanic ash was found on a camera around 0500 on 1 July. Air shocks that were intermittently observed from 1600 on 29 June to 1 July may have occurred in association with eruptions, the last occurring between 0400 and 0500 on 1 July. A field survey conducted by the Hot Springs Research Institute of Kangawa Prefecture and JMA on 2 July confirmed continued forceful emissions of steam at the new fumarole, which had grown to 20 m in diameter, and was designated Crater 15-1. Three other new fumaroles were also observed around this crater.

No low-frequency earthquakes or volcanic tremors were recorded in July, but active degassing at Crater 15-1 and adjacent fumaroles continued. In a field survey on 6 August 2015, material described as "dark gray soil" was observed around the fumarole, inside the crater rim. Thermal infrared observation showed a high-temperature area on the E side of the crater from August through October. A single, minor seismic event was recorded on 17 August, the first one since 3 July. JMA downgraded the Alert Level at the volcano from 3 (Do not approach the volcano) to 2 (Do not approach the crater) on 11 September, and no further changes in the tiltmeter or strainmeter data were observed after August.

Field surveys on 3 and 29 September indicated that "dark gray soil" continued to be ejected from Crater 15-1, but the scale of the explosions were small and ejection heights were lower than the crater rim. Strong degassing was still occurring at the crater and all other fumaroles. By 20 November the slight weakening of the emissions from Crater 15-1 and overall stability and low seismic activity led JMA to reduce the Volcanic Alert Level further to 1 (Potential for increased activity). Field observations on 7 and 9 December 2015 confirmed continuing strong degassing with plumes to 600 m in the area around Owakudani, but no new ejecta.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); The Mainichi, Japan's National Daily since 1922 (URL: http://mainichi.jp/english/); The Japan Times (URL: http://www.japantimes.co.jp/news/2015/05/07/national/volcano-alert-raised-mount-hakone/#.WHkqQHrcDy1).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 8 confirmed Holocene eruptive periods.

2015 Jun 29 - 2015 Jul 1 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Owakudani hot springs, 1 km N of Kamiyama dome
2015 Jun 29 - 2015 Jul 1 Evidence from Observations: Reported

List of 12 Events for Episode 1 at Owakudani hot springs, 1 km N of Kamiyama dome

Start Date End Date Event Type Event Remarks
2015 Apr 17 2015 May 15 Deformation (inflation) According to a news article, the ground level in the Owakudani hot spring area had risen 12 cm during 17 April-15 May; the deformation occurred in an area 200 m in diameter.
2015 Apr 26 2015 May 31
(in or before)
Seismicity (volcanic) JMA reported an increased seismicity to tens of daily events beginning 26 April 2015. On 5 May, three more small seismic events were recorded in the Yumoto area. There were 21 additional small seismic events in the Yumoto area during May 2015. The daily total of all seismic events rose significantly to 442 on 15 May, the highest since 2001.
2015 Jun 29    - - - - Seismicity (tremor) Volcanic tremor lasting for around five minutes started at 0732.
2015 Jun 29    - - - - Ashfall At around 1245, fallout was observed in an area up to 1.2 km N and NE of the Owakudani hot spring complex. This fallout was interpreted by JMA to be sediment and debris ejected from a "blowhole" that formed a new fumarole at Owakudani. A field survey conducted on 30 June observed a mound of volcanic ash around the new fumarole. Additionally, volcanic ash was observed near the Owakudani Station of the Hakone Ropeway (a resort tramway) located about 300 m NNW of the hot springs area. Additional volcanic ash was found on a camera around 0500 on 1 July.
2015 Jun 29 2015 Jul 1 Explosion Air shocks that were intermittently observed from 1600 on 29 June to 1 July may have occurred in association with eruptions, the last occurring between 0400 and 0500 on 1 July.
2015 Jun 29 2015 Jul 1 Infrasound Air shocks that were intermittently observed from 1600 on 29 June to 1 July may have occurred in association with eruptions, the last occurring between 0400 and 0500 on 1 July.
2015 Jun 29    - - - - VEI (Explosivity Index) VEI 1
2015 Jul 2    - - - - Fumarolic or Solfataric A field survey conducted by the Hot Springs Research Institute of Kangawa Prefecture and JMA confirmed continued forceful emissions of steam at the new fumarole, which had grown to 20 m in diameter, and was designated Crater 15-1. Three other new fumaroles were also observed around this crater.
2015 Jul 2    - - - - Crater A field survey conducted by the Hot Springs Research Institute of Kangawa Prefecture and JMA on 2 July confirmed continued forceful emissions of steam at the new fumarole, which had grown to 20 m in diameter, and was designated Crater 15-1. Three other new fumaroles were also observed around this crater.
2015 Jul 7
(in or before)
   - - - - Property Damage According to a news article, a drone that surveyed the Owakudani hot spring district recorded damage to three hot spring supply facilities.
2015 Aug 6    - - - - Observation In a field survey, material described as "dark gray soil" was observed around the fumarole, inside the crater rim.
2015 Sep 3
(in or before)
2015 Sep 29
(in or before)
Observation Field surveys on 3 and 29 September indicated that "dark gray soil" continued to be ejected from Crater 15-1, but the scale of the explosions were small and ejection heights were lower than the crater rim.

1170 ± 100 years Confirmed Eruption  

Episode 1 | Eruption Episode Owakudani, Hk-Ow 3-5 tephras
1170 ± 100 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 7 Events for Episode 1 at Owakudani, Hk-Ow 3-5 tephras

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash
1933 May 10    - - - - Fatalities
1951 Nov 5    - - - - Fatalities
1952 Mar 27    - - - - Fatalities
1953 Jul 26    - - - - Fatalities
1972 Oct 2    - - - - Fatalities

0050 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode NE of Kamiyama, Hk-Ow2 tephra
0050 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 4 Events for Episode 1 at NE of Kamiyama, Hk-Ow2 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow

1050 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode NE of Kamiyama, Hk-Ow1 tephra
1050 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 3 Events for Episode 1 at NE of Kamiyama, Hk-Ow1 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow

1200 BCE (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode NW side of Kami-yama (Kanmuriga-take)
1200 BCE (?) - Unknown Evidence from Isotopic: 14C (calibrated)

List of 6 Events for Episode 1 at NW side of Kami-yama (Kanmuriga-take)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Lava spine
1200 BCE
(?)
   - - - - VEI (Explosivity Index)

1400 BCE ± 100 years Confirmed Eruption  

Episode 1 | Eruption Episode NW side of Kami-yama (Kanmuriga-take)
1400 BCE ± 100 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 3 Events for Episode 1 at NW side of Kami-yama (Kanmuriga-take)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Avalanche
   - - - -    - - - - Edifice Destroyed Collapse/avalanche

3700 BCE ± 100 years Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Futago-yama
3700 BCE ± 100 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 3 Events for Episode 1 at Futago-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
3700 BCE ± 100 years    - - - - VEI (Explosivity Index)

6000 BCE ± 100 years Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Kami-yama, Hk-Km5 tephra
6000 BCE ± 100 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 3 Events for Episode 1 at Kami-yama, Hk-Km5 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
6000 BCE ± 100 years    - - - - VEI (Explosivity Index)
Deformation History

There is no Deformation History data available for Hakoneyama.

Emission History

There is no Emissions History data available for Hakoneyama.

Photo Gallery

Hakoneyama volcano, seen here from the W, is a broad volcano with two large calderas. A group of lava domes formed in the center of the caldera. The highest dome, Kamiyama, forms the high point of the complex, topped by clouds in the center of the photo. The caldera formed during two large Pleistocene eruptions. An eruption took place around 3,000 years ago and seismic swarms have occurred frequently during the 20th century.

Photo by Lee Siebert, 1977 (Smithsonian Institution).
The flanks of a group of post-caldera lava domes are to the left above Lake Ashi in SW Hakone caldera. Lake Ashi formed when an avalanche from Kamiyama, the highest of the central lava domes, blocked river valleys that drain to the E through a breach in the caldera wall.

Photo by Lee Siebert, 1977 (Smithsonian Institution).
Lake Ashi, seen here from the SE, occupies the SW corner of Hakone caldera. Hakoneyama contains two calderas, the largest of which is 10 x 11 km. The arcuate caldera rim is to the left and the flanks of a group of post-caldera cones form the right-hand shoreline. Post-caldera eruptions have constructed a half dozen lava domes along a SW-NE trend across the center of the calderas. An eruption took place around 3,000 years ago and seismic swarms occurred frequently during the 20th century.

Photo by Lee Siebert, 1963 (Smithsonian Institution).
Aerial cable cars stretching across Owakudani provide a view of one of the many thermal areas in Hakone caldera. Hot spring resorts surround a complex of lava domes in the center of the caldera.

Photo by Lee Siebert, 1963 (Smithsonian Institution).
Kamiyama, the highest of a group of lava domes forming the central cone complex of Hakoneyama caldera, rises E of Ashinoko (Lake Ashi). The lake formed about 3,100 years ago when collapse of the NW side of Kamiyama dammed the Hayakawa river valley at the N end of the lake (lower left). Dome growth at Kamiyama occurred about 2,900 years ago.

Photo by Lee Siebert, 1977 (Smithsonian Institution).
GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Smithsonian Sample Collections Database

The following 60 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number Sample Description Lava Source Collection Date
NMNH 105869-00 Pigeonite -- --
NMNH 106410-00 Hypersthene -- --
NMNH 107431-00 Pargasite -- --
NMNH 108936 Augite Andesite KAMI-YAMA CONE --
NMNH 108937 Dacite -- --
NMNH 108938 Augite Andesite -- --
NMNH 108939 Olivine Basalt -- --
NMNH 108942 Andesite Pumice -- --
NMNH 108943 Dacitic Andesite MAKU-YAMA DOME --
NMNH 108944 Hypersthene Andesite KINTOKI-SAN CONE --
NMNH 108945 Andesite -- --
NMNH 108949 Hypersthene Andesite -- --
NMNH 108950 Hypersthene Andesite -- --
NMNH 108951 Hypersthene Andesite -- --
NMNH 108955 Hypersthene Andesite -- --
NMNH 108956 Augite Andesite KAMIHUTAGO-YAMA CONE --
NMNH 108957 Andesite -- --
NMNH 108958 Hornblende Andesite -- --
NMNH 108960 Welded Tuff -- --
NMNH 108961 Augite Andesite -- --
NMNH 108965 Hypersthene Andesite -- --
NMNH 108966 Augite Andesite -- --
NMNH 108967 Hypersthene Andesite -- --
NMNH 108971 Augite Andesite -- --
NMNH 108972 Hypersthene Andesite -- --
NMNH 108975 Hypersthene Andesite -- --
NMNH 108976 Augite Andesite -- --
NMNH 108977 Hypersthene Andesite -- --
NMNH 112898 Pigeonite Andesite -- --
NMNH 112899 Pyroxene Andesite -- --
NMNH 112899 Pyroxene Andesite -- --
NMNH 112900 Andesite -- --
NMNH 112900 Andesite -- --
NMNH 112901 Hypersthene Andesite -- --
NMNH 112901 Hypersthene Andesite -- --
NMNH 112902 Hypersthene Andesite -- --
NMNH 112902 Hypersthene Andesite -- --
NMNH 112903 Hypersthene Dacite -- --
NMNH 112903 Hypersthene Dacite -- --
NMNH 112904 Augite Andesite SIMOHUTAGO-YAMA CONE --
NMNH 112904 Augite Andesite SIMOHUTAGO-YAMA CONE --
NMNH 112904 Augite Andesite SIMOHUTAGO-YAMA CONE --
NMNH 112905 Hypersthene Andesite KOMA-GATAKE CONE --
NMNH 112905 Hypersthene Andesite KOMA-GATAKE CONE --
NMNH 113055 Hypersthene Andesite -- --
NMNH 117801-12 Augite-Pigeonite-Hypersthene Andesite Old Somma --
NMNH 117801-18 Augite Andesite Simohutago-yama --
NMNH 117801-19 Augite Andesite Simohutago-yama --
NMNH 117801-21 Hypersthene-Hornblende-Quartz Dacite -- --
NMNH 117801-25 Olivine Andesite Old Somma --
NMNH 117801-27 Obsidian -- --
NMNH 117801-30 Hypersthene-Olivine Andesite Old Somma --
NMNH 117801-32 Hypersthene Dacite -- --
NMNH 117801-35 Pumice -- --
NMNH 117801-4 Augite-Hypersthene Andesite Old Somma --
NMNH 117801-5 Hornblende-Hypersthene Andesite -- --
NMNH 117801-6 Andesite Old Somma --
NMNH M6542-00 Fayalite -- --
NMNH M6543-00 Fayalite -- --
NMNH M6544-00 Fayalite -- --
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