Last Updated : March 31, 2015

Aerial photographs had been taken around Nishinoshima Island


  Geospatial Information Authority of Japan (GSI) took aerial photographs of the area around Nishinoshima Island by its survey aerial vehicle Kunikaze III launched from Io To Island, Ogasawara Village, Tokyo. And GSI measured area, highest elevation and volume and these results were published.

  These photographs of the Ogasawara islands were taken at the beginning of December with the cooperation of the Ministry of Defense, and the area around Nishinoshima Island was photographed on December 4th and 10th (see Attachment 1 and Attachment 2). GSI's photography of the area around Nishinoshima Island had previously been taken on July 4th by means of an UAV (Unmanned Aerial Vehicle). 

Results of analisis

Through the analysis of aerial photographs taken of the area around Nishinoshima Island, the following results were obtained.
  • Area was approximately 2.27 square kilometers (December 4th) and 2.29 square kilometers (December 10th). This is approximately twice the size of the area of 1.08 square kilometers confirmed on July 4th.
  • The elevation of highest point was approximately 110 meters (reference value: As of December 4th). The highest elevation on July 4th was 74 meters.
  • The volume of newly emitted lava over the sea level was approximately 49,700,000 cubic meters (As of December 4th). This represented an increase of approximately twice as much as the volume of 22,200,000 cubic meters confirmed on July 4th.
Moreover, on December 10th, 3D observation by means of multiple photographs was difficult due to cloudy skies, so it was not possible to measure the elevation or the volume of newly emitted lava on that date.

Release of photos and analysis results

The present aerial photographs are being published on the Internet under "GSI Maps". Furthermore, 3D images of the area around Nishinoshima Island (Attachment 4), topographic interpretation maps (Attachment 5-1 and Attachment 5-2), and elevation data are also published.

 Related website for information relating to eruption activity in area around Nishinoshima Island (Japanese only)


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