Logo link to homepage

Zaozan [Zaosan]

Photo of this volcano
  • Japan
  • Complex
  • 1940 CE
  •  
  • Country
  • Primary Volcano Type
  • Last Known Eruption
  •  
  • 38.144°N
  • 140.44°E

  • 1841 m
    6040 ft

  • 283190
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number
Most Recent Weekly Report: 24 January-30 January 2018 Citation IconCite this Report

JMA reported that tremor was detected at Zaozan on 28 and 30 January, and minor inflation at the S part of the volcano was recorded. There were 12 volcanic earthquakes detected on 31 January. JMA raised the Alert level to 2 (on a 5-level scale), noting the increased potential for a small eruption.

Source: Japan Meteorological Agency (JMA)


Most Recent Bulletin Report: September 1992 (BGVN 17:09) Citation IconCite this Report

Earthquake and numerous aftershocks, but no surface changes evident

A seismic shock of M 4.7 occurred at 1758 on 1 September a few kilometers ESE of the summit. The shock was felt at JMA intensity IV near the volcano, and was weakly felt at Sendai (35 km E), Fukushima (45 km S), and Onahama (135 km E). Aftershocks were numerous, but declined toward mid-September. The high seismicity was the first at the volcano since July 1990, when there were many small earthquakes below the summit. Surveys of fumarolic areas on 5 September revealed no changes in temperature from the last survey in 1990.

Information Contacts: JMA.

Weekly Reports - Index


2018: January


24 January-30 January 2018 Citation IconCite this Report

JMA reported that tremor was detected at Zaozan on 28 and 30 January, and minor inflation at the S part of the volcano was recorded. There were 12 volcanic earthquakes detected on 31 January. JMA raised the Alert level to 2 (on a 5-level scale), noting the increased potential for a small eruption.

Source: Japan Meteorological Agency (JMA)


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.

09/1992 (BGVN 17:09) Earthquake and numerous aftershocks, but no surface changes evident




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


September 1992 (BGVN 17:09) Citation IconCite this Report

Earthquake and numerous aftershocks, but no surface changes evident

A seismic shock of M 4.7 occurred at 1758 on 1 September a few kilometers ESE of the summit. The shock was felt at JMA intensity IV near the volcano, and was weakly felt at Sendai (35 km E), Fukushima (45 km S), and Onahama (135 km E). Aftershocks were numerous, but declined toward mid-September. The high seismicity was the first at the volcano since July 1990, when there were many small earthquakes below the summit. Surveys of fumarolic areas on 5 September revealed no changes in temperature from the last survey in 1990.

Information Contacts: JMA.

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 43 confirmed Holocene eruptive periods.

1940 May 18 - 1940 May 18 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Okama
1940 May 18 - 1940 May 18 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity weak or small
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Blocks
1940 May 18    - - - - VEI (Explosivity Index)

[ 1939 Jul ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1939 Jul - Unknown Evidence from Unknown

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Lahar or Mudflow
1939 Jul    - - - - VEI (Explosivity Index)

[ 1927 ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1927 - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1927    - - - - VEI (Explosivity Index)

[ 1906 ] Discredited Eruption

1905 Confirmed Eruption Max VEI: 1 (?)

Episode 1 | Eruption Episode Okama
1905 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1905    - - - - VEI (Explosivity Index)

[ 1897 Jan 14 - 1897 Jan 14 ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1897 Jan 14 - 1897 Jan 14 Evidence from Unknown

List of 4 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Volcanic "smoke"
   - - - -    - - - - Audible Sounds
1897 Jan 14    - - - - VEI (Explosivity Index)

[ 1896 Sep 1 (?) ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1896 Sep 1 (?) - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1896 Sep 1
(?)
   - - - - VEI (Explosivity Index)

1896 Mar 8 - 1896 Mar 8 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Okama
1896 Mar 8 - 1896 Mar 8 Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash weak or small
1896 Mar 8    - - - - VEI (Explosivity Index)

1895 Aug 22 - 1895 Sep 28 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1895 Aug 22 - 1895 Sep 28 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage
1895 Aug 22    - - - - VEI (Explosivity Index)

1895 Feb 15 - 1895 Mar 22 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Okama
1895 Feb 15 - 1895 Mar 22 Evidence from Observations: Reported

List of 6 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Fauna Kill Aquatic.
1895 Feb 15    - - - - VEI (Explosivity Index)

1894 Jul 3 - 1894 Jul 3 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1894 Jul 3 - 1894 Jul 3 Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
1894 Jul 3    - - - - VEI (Explosivity Index)

[ 1890 ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1890 - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1890    - - - - VEI (Explosivity Index)

1873 Aug - 1873 Sep Confirmed Eruption Max VEI: 1 (?)

Episode 1 | Eruption Episode Okama
1873 Aug - 1873 Sep Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1873 Aug    - - - - VEI (Explosivity Index)

1867 Oct 21 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1867 Oct 21 - Unknown Evidence from Observations: Reported

List of 5 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage Uncertain
1867 Oct 21    - - - - Fatalities
1867 Oct 21    - - - - VEI (Explosivity Index)

1833 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1833 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
1833    - - - - VEI (Explosivity Index)

1831 Nov 22 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1831 Nov 22 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Lahar or Mudflow Uncertain
1831 Nov 22    - - - - VEI (Explosivity Index)

1830 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1830 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1830    - - - - VEI (Explosivity Index)

1822 May 1 Confirmed Eruption  

Episode 1 | Eruption Episode
1822 May 1 - Unknown Evidence from Observations: Reported

List of 1 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain

1821 Jan 27 - 1821 May 1 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1821 Jan 27 - 1821 May 1 Evidence from Observations: Reported

List of 6 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Lahar or Mudflow
1821 Jan 27    - - - - VEI (Explosivity Index)
1821 May 1    - - - - VEI (Explosivity Index)

1809 Jun 12 - 1809 Dec 29 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1809 Jun 12 - 1809 Dec 29 Evidence from Observations: Reported

List of 6 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Fauna Kill Aquatic.
   - - - -    - - - - Property Damage Uncertain
1809 Jun 12    - - - - VEI (Explosivity Index)

1806 Jul 12 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1806 Jul 12 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1806 Jul 12    - - - - VEI (Explosivity Index)

1804 May (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1804 May (?) - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1804 May
(?)
   - - - - VEI (Explosivity Index)

1796 Mar 24 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1796 Mar 24 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1796 Mar 24    - - - - VEI (Explosivity Index)

1794 Sep 22 - 1794 Dec (in or after) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode SE side of Okama
1794 Sep 22 - 1794 Dec (in or after) Evidence from Observations: Reported

List of 4 Events for Episode 1 at SE side of Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
   - - - -    - - - - Property Damage
1794 Sep 22    - - - - VEI (Explosivity Index)

1694 May 29 - 1694 Aug 30 (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1694 May 29 - 1694 Aug 30 (?) Evidence from Observations: Reported

List of 7 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Fauna Kill Aquatic.
   - - - -    - - - - Property Damage
1694 May 29    - - - - VEI (Explosivity Index)

1670 Apr 26 - 1670 Sep 26 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Okama
1670 Apr 26 - 1670 Sep 26 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash
1670 Apr 26    - - - - VEI (Explosivity Index)
1670 Aug 13    - - - - VEI (Explosivity Index)

1669 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Okama
1669 - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Property Damage
1669    - - - - VEI (Explosivity Index)

1668 Aug Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1668 Aug - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1668 Aug    - - - - VEI (Explosivity Index)

1641 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1641 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1641    - - - - VEI (Explosivity Index)

1630 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1630 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1630    - - - - VEI (Explosivity Index)

1623 May 15 (?) - 1624 Nov 15 (?) Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Okama
1623 May 15 (?) - 1624 Nov 15 (?) Evidence from Observations: Reported

List of 6 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Blocks
   - - - -    - - - - Audible Sounds
1623 May 15
(?)
   - - - - VEI (Explosivity Index)
1624 Feb 6    - - - - VEI (Explosivity Index)

1622 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1622 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1622    - - - - VEI (Explosivity Index)

1620 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1620 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
   - - - -    - - - - Fauna Kill Terrestrial.
1620    - - - - VEI (Explosivity Index)

1400 ± 100 years Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Goshiki-dake area, Z-To11 tephra
1400 ± 100 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 4 Events for Episode 1 at Goshiki-dake area, Z-To11 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
1400 ± 100 years    - - - - VEI (Explosivity Index)

[ 1350 (?) ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1350 (?) - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1350
(?)
   - - - - VEI (Explosivity Index)

[ 1331 - 1333 ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
1331 - 1333 Evidence from Unknown

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1331    - - - - VEI (Explosivity Index)

1230 Nov 29 (?) Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1230 Nov 29 (?) - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
   - - - -    - - - - Pumice
1230 Nov 29
(?)
   - - - - VEI (Explosivity Index)

1227 Oct (?) Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Okama
1227 Oct (?) - Unknown Evidence from Observations: Reported

List of 5 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Blocks
   - - - -    - - - - Property Damage
1227 Oct
(?)
   - - - - VEI (Explosivity Index)

1183 May 28 (?) Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Okama
1183 May 28 (?) - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Okama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1183 May 28
(?)
   - - - - VEI (Explosivity Index)

0884 (?) Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Okama, Z-To10 tephra?
0884 (?) - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Okama, Z-To10 tephra?

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
0884
(?)
   - - - - VEI (Explosivity Index)

[ 0773 Nov (?) ] Uncertain Eruption

Episode 1 | Eruption Episode Okama
0773 Nov (?) - Unknown Evidence from Unknown

0300 ± 200 years Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode Goshiki-dake area, Z-To9 tephra
0300 ± 200 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 4 Events for Episode 1 at Goshiki-dake area, Z-To9 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
0300 ± 200 years    - - - - VEI (Explosivity Index)

1600 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake
1600 BCE (?) - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash

2000 BCE ± 500 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake
2000 BCE ± 500 years - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1 at Goshiki-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash

2300 BCE ± 75 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area, Z-To8 tephra
2300 BCE ± 75 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake area, Z-To8 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

2600 BCE ± 200 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area, Z-To7 tephra
2600 BCE ± 200 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake area, Z-To7 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

3350 BCE ± 50 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area, Z-To6 tephra
3350 BCE ± 50 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake area, Z-To6 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity

3850 BCE ± 200 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area, Z-To5 tephra
3850 BCE ± 200 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 3 Events for Episode 1 at Goshiki-dake area, Z-To5 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash

4150 BCE ± 200 years Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area, Z-To5b tephra
4150 BCE ± 200 years - Unknown Evidence from Isotopic: 14C (calibrated)

List of 3 Events for Episode 1 at Goshiki-dake area, Z-To5b tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash

5500 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area
5500 BCE (?) - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake area

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash

5600 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake, Z-To5a tephra
5600 BCE (?) - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake, Z-To5a tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

7600 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Goshiki-dake area
7600 BCE (?) - Unknown Evidence from Isotopic: 14C (calibrated)

List of 2 Events for Episode 1 at Goshiki-dake area

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Ash
Deformation History

There is data available for 1 deformation periods. Expand each entry for additional details.


Deformation during 2011 Mar 11 - 2011 Mar 11 [Subsidence; Observed by InSAR]

Start Date: 2011 Mar 11 Stop Date: 2011 Mar 11 Direction: Subsidence Method: InSAR
Magnitude: 8.000 cm Spatial Extent: 20.00 km Latitude: 38.000 Longitude: 140.000

Remarks: Subsidence of plutonic bodies triggered by Mw 9.0 Tohoku earthquake

Figure (see Caption)

Close-up interferograms. Blue squares indicate geothermal power plants. GEONET stations are indicated by numbered circles, with the colour inside indicating the GPS displacements in the LOS direction.

From: Takada and Fukushima 2013.


Reference List: Takada and Fukushima 2013; Ozawa and Fujita 2013.

Full References:

Ozawa T, Fujita E, 2013. Local deformations around volcanoes associated with the 2011 off the Pacific coast of Tohoku earthquake. J. Geophys. Res., 118, 390-405. https://doi.org/10.1029/2011JB009129

Takada and Fukushima, 2013. Volcanic subsidence triggered by the 2011 Tohoku earthquake in Japan. Nature Geoscience, 6: 637-641.

Emission History

There is no Emissions History data available for Zaozan [Zaosan].

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

There are no samples for Zaozan [Zaosan] in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites