Sashiusudake [Baransky]

Photo of this volcano
  • Japan - administered by Russia
  • Kuril Islands
  • Stratovolcano
  • 1951 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 45.1°N
  • 148.019°E

  • 1125 m
    3690 ft

  • 290080
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Bulletin Report: December 1992 (BGVN 17:12) Citation IconCite this Report


1991 hydrothermal explosion near geothermal drillhole

Many hot and boiling mineralized springs are active near Baransky. Geothermal surveys have been carried out in a zone 2-4 km SW of the volcano, and a geothermal station is being built there. Temperature data from several boreholes show a strong increase in 1989, 4-5 months before the eruption of Ivan Grozny, 13 km SW. Temperatures decreased after the eruption. Gas composition (table 1), temperature, and location of fumaroles in the SW-flank explosion crater remained unchanged in 1990-91.

Table 1. Composition of gases from the Baransky area: fumaroles in the SW-flank explosion crater (samples 1-4); the bottom of the Kipyaschaya River drainage (6); geothermal drillholes (7-8). Analyses by U.A. Taran and U.A. Ignatorich. Data courtesy of G. Steinberg.

[Skip text table]
    Sample           1     2      3      4      5      6      7    8
    Temp. (°C)     100    99    100    101     98     61    170   47
    H2O (mole %)  75.5   85.8   97.01  98.7   99.1    --    99.94 47

    Volume % of dry gas
    CO2           92.45  94.20  94.20  91.20  58.24  33.00  70.0  88.0
    H2S            5.71   4.60   4.51   6.00   33.0   2.2   15.1   0
    SO2            0.18   0.15   --     --      --    --     --    --
    H2             0.001  0.002  0.006  0.001   0.064 0.001  9.7   0.003
    CH4            0.073  0.070  0.10   0.01    1.27  1.20   3.3   0.03
    HCl            0.01   0      0      0       0.01  --     --    --
    N2             1.22   1.18   1.20   2.10    7.43 63.0   11.0  12.0

An exploration well into a zone of hot water 4.5 km SW of the summit (in the Kipyaschaya River valley) was drilled in the summer of 1991. Drilling was temporarily halted in early August, but no casing was installed. Two weeks later, a hydrothermal explosion occurred ~50 m upslope, forming a crater >10 m in diameter. A mixture of vapor, water, and a large quantity of rock fragments was erupted for several days, destroying vegetation within 50 m. The explosion was believed to have occurred when hot water moved up the borehole after drilling ceased, and escaped through its uncased walls into a permeable fissured zone near the surface.

Information Contacts: G. Steinberg, Yuzhno-Sakhalinsk.

The Global Volcanism Program has no Weekly Reports available for Sashiusudake [Baransky].

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.

01/1988 (SEAN 13:01) Crater lake level drops; flank fumarolic activity

11/1988 (SEAN 13:11) Fumarolic activity

12/1992 (BGVN 17:12) 1991 hydrothermal explosion near geothermal drillhole




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


January 1988 (SEAN 13:01) Citation IconCite this Report


Crater lake level drops; flank fumarolic activity

During observations 4-7 October 1987, five fumaroles in an explosion crater on the SW flank were forcefully emitting vapor. Jets rose 3-5 m and had temperatures of 99-107°C. In the summit crater, a 40-m-diameter explosion crater in the lava dome contained a smaller lake than in the past. The lake was <0.2 m deep, the surface was only 10 x 15 m, and the water was cold. Weak vaporization was occurring at two points on the dome (vaporizing temperatures are 40-45°C). No fumaroles were observed but there were many areas of sulfur deposits.

Information Contacts: G. Steinberg, Yuzhno-Sakhalinsk.


November 1988 (SEAN 13:11) Citation IconCite this Report


Fumarolic activity

During an October visit to the crater, activity remained at previous levels. Fumaroles were concentrated in five groups with gas temperatures ranging from 98 to 108°C. Gas was released under pressure in four of the five groups, to 2-6 m height.

Information Contacts: G. Steinberg, Yuzhno-Sakhalinsk.


December 1992 (BGVN 17:12) Citation IconCite this Report


1991 hydrothermal explosion near geothermal drillhole

Many hot and boiling mineralized springs are active near Baransky. Geothermal surveys have been carried out in a zone 2-4 km SW of the volcano, and a geothermal station is being built there. Temperature data from several boreholes show a strong increase in 1989, 4-5 months before the eruption of Ivan Grozny, 13 km SW. Temperatures decreased after the eruption. Gas composition (table 1), temperature, and location of fumaroles in the SW-flank explosion crater remained unchanged in 1990-91.

Table 1. Composition of gases from the Baransky area: fumaroles in the SW-flank explosion crater (samples 1-4); the bottom of the Kipyaschaya River drainage (6); geothermal drillholes (7-8). Analyses by U.A. Taran and U.A. Ignatorich. Data courtesy of G. Steinberg.

[Skip text table]
    Sample           1     2      3      4      5      6      7    8
    Temp. (°C)     100    99    100    101     98     61    170   47
    H2O (mole %)  75.5   85.8   97.01  98.7   99.1    --    99.94 47

    Volume % of dry gas
    CO2           92.45  94.20  94.20  91.20  58.24  33.00  70.0  88.0
    H2S            5.71   4.60   4.51   6.00   33.0   2.2   15.1   0
    SO2            0.18   0.15   --     --      --    --     --    --
    H2             0.001  0.002  0.006  0.001   0.064 0.001  9.7   0.003
    CH4            0.073  0.070  0.10   0.01    1.27  1.20   3.3   0.03
    HCl            0.01   0      0      0       0.01  --     --    --
    N2             1.22   1.18   1.20   2.10    7.43 63.0   11.0  12.0

An exploration well into a zone of hot water 4.5 km SW of the summit (in the Kipyaschaya River valley) was drilled in the summer of 1991. Drilling was temporarily halted in early August, but no casing was installed. Two weeks later, a hydrothermal explosion occurred ~50 m upslope, forming a crater >10 m in diameter. A mixture of vapor, water, and a large quantity of rock fragments was erupted for several days, destroying vegetation within 50 m. The explosion was believed to have occurred when hot water moved up the borehole after drilling ceased, and escaped through its uncased walls into a permeable fissured zone near the surface.

Information Contacts: G. Steinberg, Yuzhno-Sakhalinsk.

Eruptive History


Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1951 Jul 15 ± 45 days Unknown Confirmed 1 Historical Observations
1570 ± 30 years Unknown Confirmed   Radiocarbon (uncorrected)
1460 ± 30 years Unknown Confirmed   Radiocarbon (uncorrected)

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.

Photo Gallery


Strong solfataric activity continues at a SW-flank geothermal exploration area, seen here from the west. A small hydrothermal explosion took place at an exploratory well there in 1992. The Baransky volcanic complex consists of an eroded Pleistocene volcano that is capped by a Holocene stratovolcano. A summit lava dome is cut by a NW-trending chain of small explosion craters. The only historical eruption occurred in 1951, when local inhabitants reported weak explosive activity at the summit.

Photo by T. Vendelin (courtesy of Genrich Steinberg, Institute for Marine Geology and Geophysics, Yuzhno-Sakhalinsk).
See title for photo information.
Steam rises from fumaroles on a SW-flank crater of Baransky volcano on central Iturup Island. The summit crater (top) is breached to the NNW. A broad, low lava dome, 500-m wide and 40-50 m high occupies the crater, which has fed lava flows that cover wide areas on the northern and western flanks. The only historical eruption at Baransky occurred in 1951, when local inhabitants reported weak explosive activity at the summit.

Photo by T. Vendelin (courtesy of Genrich Steinberg (Institute for Marine Geology and Geophysics, Yuzhno-Sakhalinsk).
See title for photo information.
The SE slopes of Baransky volcano tower above steep sea cliffs along the Pacific Ocean coast of Iturup Island. Lava flows from Baransky (also known as Sashiusu-dake) descended 4-5 km SE to reach the Pacific Ocean along a broad front north of the location of this photo. The only historical eruption consisted of weak explosive activity at the summit in 1951. Strong solfataric activity continues from the summit and flank craters, and the SW-flank geothermal field contains hot springs and geysers.

Photo by Alexander Rybin, 1999 (Institute of Marine Geology and Geophysics, Yuzhno-Sakhalin).
See title for photo information.

Smithsonian Sample Collections Database


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

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