Global Volcanism Program

The Global Volcanism Program has no activity reports for Iwakisan.

The Global Volcanism Program has no Weekly Reports available for Iwakisan.

The Global Volcanism Program has no Bulletin Reports available for Iwakisan.

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.

Synonyms

Tugaru-Huzi | Tsugaru-Fuji | Okuno-Fuji | Asobenomori

Craters

Feature Name

Feature Type

Elevation

Latitude

Longitude

Tanemakishiro
Tanemakisiro

Crater

Torinoumi

Crater

Domes

Feature Name

Feature Type

Elevation

Latitude

Longitude

Iwaki-san

Dome

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude

283270

1863 CE

1625 m / 5330 ft

40.656°N
140.303°E

Volcano Types

Stratovolcano
Lava dome(s)

Rock Types

Major
Andesite / Basaltic Andesite

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km

918
13,229
465,065
1,617,801

Geological Summary

Iwakisan volcano, symmetrical on all but its western flanks, has been called the Fujisan of the Tsugaru district. The 2-km-wide summit crater is filled by a lava dome flanked by six explosion craters. Three lava domes are found on the western and southern flanks of the andesitic volcano, the NW-most active volcano in Honshu. Historical eruptions have been reported here since 1600 CE and have consisted primarily of small-to-moderate phreatic explosions.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Japan Meteorological Agency, 1996. National Catalogue of the Active Volcanoes in Japan (second edition). Tokyo: Japan Meteorological Agency, 502 p (in Japanese).

Japan Meteorological Agency, 2013. National Catalogue of the Active Volcanoes in Japan (fourth edition, English version). Japan Meteorological Agency.

Kudo T, Hoshizumi H, 2006-. Catalog of eruptive events within the last 10,000 years in Japan, database of Japanese active volcanoes. Geol Surv Japan, AIST, http://riodb02.ibase.aist.go.jp/db099/eruption/index.html.

Kuno H, 1962. Japan, Taiwan and Marianas. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 11: 1-332.

Murayama I, 1987. Volcanoes of Japan (I). Tokyo: Daimedo, 315 p (2nd edition, in Japanese).

Nakano S, Yamamoto T, Iwaya T, Itoh J, Takada A, 2001-. Quaternary Volcanoes of Japan. Geol Surv Japan, AIST, http://www.aist.go.jp/RIODB/strata/VOL_JP/.

Eruptive History

There is data available for 29 Holocene eruptive periods.

Start Date	Stop Date	Eruption Certainty	VEI	Evidence	Activity Area or Unit
1863 Mar 23	Unknown	Confirmed	1	Historical Observations
[ 1856 May 20 ]	[ Unknown ]	Uncertain	2
[ 1848 Jan 18 ]	[ Unknown ]	Uncertain	2
1845 Apr 4	Unknown	Confirmed	2	Historical Observations
1844 Apr 7	Unknown	Confirmed	2	Historical Observations	Summit and south flank?
[ 1833 Apr 11 ]	[ Unknown ]	Uncertain	2
[ 1807 Mar 31 ]	[ Unknown ]	Uncertain	2
[ 1800 May 11 ]	[ Unknown ]	Uncertain	2
[ 1794 Apr 3 ]	[ Unknown ]	Uncertain	2
[ 1793 Apr 2 ]	[ Unknown ]	Uncertain	2
1790 Oct 9	Unknown	Confirmed	2	Historical Observations
[ 1783 Dec 3 ]	[ Unknown ]	Uncertain	2
1782 Dec 1 ± 30 days	1783 Mar 12	Confirmed	2	Historical Observations
[ 1782 Apr 12 ]	[ Unknown ]	Uncertain	2		South flank
[ 1769 ]	[ Unknown ]	Uncertain	2
[ 1709 Apr 23 ]	[ Unknown ]	Uncertain	2
[ 1694 Jun 19 ]	[ Unknown ]	Uncertain	2
[ 1672 Jul 12 ]	[ 1672 Jul 28 ]	Uncertain	2
1618 Jan 31	Unknown	Confirmed	2	Historical Observations
[ 1605 Apr 10 ]	[ Unknown ]	Uncertain	2
1604 Feb 7	Unknown	Confirmed	3	Historical Observations	Torinoumi
1600 Jul 23	1600 Jul 25	Confirmed	2	Historical Observations	Torinoumi
1600 Feb 22	Unknown	Confirmed	2	Historical Observations	Torinoumi
[ 1597 Jun 13 ]	[ Unknown ]	Uncertain	2
[ 1597 Jan ]	[ Unknown ]	Uncertain	2
0550 BCE ± 500 years	Unknown	Confirmed		Tephrochronology	Torinoumi lava dome
1050 BCE (?)	Unknown	Confirmed		Tephrochronology	Summit and central lava dome
4050 BCE (?)	Unknown	Confirmed		Tephrochronology	West summit lava dome
8050 BCE (?)	Unknown	Confirmed		Potassium-Argon	Torinoumi lava dome

Deformation History

There is no Deformation History data available for Iwakisan.

Emission History

There is no Emissions History data available for Iwakisan.

Photo Gallery

The irregular summit lava dome filling the central crater of Iwaki volcano forms the high point in this view of the SE side of the volcano. Chokai-san is the rounded peak on the left. The summit lava dome is flanked by six explosion craters. Debris-avalanche deposits from repeated collapse of the summit and flanks surround the volcano on all sides. Historical eruptions have been reported since 1597 and have consisted primarily of small-to-moderate phreatic explosions.

Copyrighted photo by Shingo Takeuchi (Japanese Quaternary Volcanoes database, RIODB, http://riodb02.ibase.aist.go.jp/strata/VOL_JP/EN/index.htm and Geol Surv Japan, AIST, http://www.gsj.jp/).

Snow-capped Iwaki stratovolcano rises above farmlands below its SE flank. The peak at the left side of the summit is Chokai-san. Iwaki volcano, symmetrical on all but its western flanks, has been called the Fuji-san of the Tsugaru district. The 2-km-wide summit crater is filled by a lava dome that forms the high point of the volcano. Historical eruptions have been reported since 1597 and have consisted primarily of small-to-moderate phreatic explosions.

Copyrighted photo by Yoshihiro Ishizuka (Japanese Quaternary Volcanoes database, RIODB, http://riodb02.ibase.aist.go.jp/strata/VOL_JP/EN/index.htm and Geol Surv Japan, AIST, http://www.gsj.jp/).

Smithsonian Sample Collections Database

The following 2 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 101496	Unidentified	IWAKI-SAN	--
NMNH 101497	Dacite	IWAKI-SAN	--

Affiliated Sites

WOVOdat
   Single Volcano View
   Temporal Evolution of Unrest
   Side by Side Volcanoes

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

Large Eruptions of Iwakisan

Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).

MIROVA

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

MODVOLC Thermal Alerts

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

EarthChem

EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).