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Ice island seen from space

Shikotan Island

Shikotan Island, or Ostrov Shikotan, is a volcanic island in the Kuril chain between Japan and Russia. The view here shows it surrounded by sea ice.

OSTROV SHIKOTAN (or Shikotan-to) is a volcanic island at the southern end of the Kuril chain. At about 43 degrees North—more than halfway to the Equator—Shikotan lies along the extreme southern edge of winter sea ice in the Northern Hemisphere.

The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-colour image of Shikotan on February 14, 2011. The island is surrounded by sea ice—swirling shapes of ghostly blue-grey. Although sea ice often forms around Shikotan, the extent varies widely from year to year, and even day to day.

The ice in this image may have formed in a matter of several days, and it is prone to moving with currents. North of the western end of Shikotan, eddies have shaped the ice into rough circles. The eddies may result from opposing winds—winds from the north pushing the ice southward, and winds from the southwest pushing the ice toward the northeast.

Uneven snow cover exaggerates the island’s rugged appearance. Multiple forces have shaped Shikotan over millions of years. Geologic studies indicate that it has been battered by multiple tsunamis, although wind, rain, and tectonic forces likely play a greater role in shaping the surface.

Part of the Pacific Ring of Fire, the island is seismically active.

See the full-size image (3.5MB) here.

NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption adapted from information issued by Michon Scott, based on image interpretation by Walt Meier and Ted Scambos, National Snow and Ice Data Center.

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Russian volcano seen from space

Kuril Island volcanoes seen from space

Kuril Island volcanoes seen from space.

IN THIS IMAGE TAKEN by an astronaut aboard the International Space station, snow cover highlights the calderas and volcanic cones that form the northern and southern ends of Onekotan Island, part of the Russian Federation in the western Pacific Ocean.

Calderas are depressions formed when a volcano empties its magma chamber in an explosive eruption and then the overlaying material collapses into the evacuated space.

The northern end of the island (image right) is dominated by the Nemo Peak volcano, which began forming within an older caldera approximately 9,500 years ago. The last recorded eruption at Nemo Peak occurred in the early 18th century.

The southern end of the island was formed by the 7.5-kilometre-wide Tao-Rusyr Caldera. The caldera is filled by Kal’tsevoe Lake and Krenitzyn Peak, a volcano that has only erupted once in recorded history (in 1952).

Extending between northeastern Japan and the Kamchatka Peninsula of Russian, the Kurils are an island arc located along the Pacific “Ring of Fire.” Island arcs form along an active boundary between two tectonic plates, where one plate is being driven beneath the other (subduction). Magma generated by the subduction process feeds volcanoes—which eventually form volcanic islands over the subduction boundary.

See the full-size image (1MB) here.

Adapted from information issued by William L. Stefanov, NASA-JSC. Image by ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre.

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Island of volcanoes

Satellite image of volcanoes on Paramushir Island.

A collection of volcanoes on Paramushir Island in the Kuril Island chain.

The Kuril Island chain is built from a line of volcanoes, an “island arc”, which extends from Russia’s Kamchatka Peninsula to northern Japan.

Island arcs form along an active boundary between two tectonic plates, with one being driven beneath the other (subduction). Magma generated by subduction feeds volcanoes—and eventually volcanic islands—over the subduction boundary.

Paramushir Island in the northern Kurils is an example of a large island built by several volcanoes over geologic time. This astronaut photograph shows the southern end of Paramushir Island after a snowfall. The western slopes of the mountains are brightly illuminated, while the eastern slopes are in shadow.

Four major volcanic centres create this part of the island. Fuss Peak (image centre left) is an isolated stratovolcano connected to the main island via an isthmus. Fuss Peak last erupted in 1854.

The southern tip of the island is occupied by the Karpinsky Group of three volcanic centres. A minor eruption of ash following an earthquake occurred on this part of the island in 1952.

The Lomonosov Group to the northeast (image centre) includes four cinder cones and a lava dome that produced several lava flows in the past, but there have been no eruptions from the Lomonosov Group in recorded history.

The most recent volcanic activity on Paramushir Island occurred in 2008 at the Chikurachki cone located along the northern coastline of the island at image top centre. The summit of this volcano (1,816 metres, or 5,958 feet, above sea level) is the highest on Paramushir Island.

Much of the Sea of Okhotsk visible in the image is covered with low clouds that often form around the islands in the Kuril chain. The clouds are generated by moisture-laden air passing over the cool sea/ocean water, and they typically wrap around the volcanic islands.

See the full-size image here (1MB, will open in a new window).

Astronaut photograph provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre. Text adapted from information issued by William L. Stefanov, NASA-JSC.

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