The Kamchatka Peninsula, along Russia’s Pacific coast, is currently the most volcanically active area in the world: four volcanoes are erupting simultaneously, and a fifth is showing sings of an impending eruption. Ash plumes from two of these volcanoes are visible in this natural-color satellite image. Along the northern (top) edge of the image Shiveluchemits a broad gray plume from the lava dome growing on its southern flank. 90 kilometers (60 miles) to the southwest a much smaller plume escapes from Bezymianny.
This image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite on August 3, 2011. Bright green vegetation covers the river floodplains and mountainsides, which gives way to bare rock and eventually snow at higher elevations.
1. Reference
2. Kamchatka Volcanic Eruption Response Team. (2011, July 28).KVERT Information Releases. Accessed August 4, 2011.
Five volcanoes on the Kamchatka Peninsula are either erupting or showing signs of impending eruption. In this image a thick plume of ash streams from a lava dome on Shiveluch Volcano.
The steep, cone-shaped volcano was shrouded in snow, and the rugged terrain was being illuminated from the south, which created dramatic shadows to the north and west. Both the mountain itself and the plume are casting a shadow (brown area) on the western and northern flanks of the volcano. Within this shadow, black rivulets of lava are visible on the northwest slopes.
According to the Kamchatka Volcanic Eruption Response Team, Klyuchevskaya Volcano has been displaying a range of volcanic activity over the past week, including gas-steam plumes reaching six kilometers (20,000 feet) above sea level, flowing lava, and Strombolian eruptions reaching 300 meters (1,000 feet) above the summit.
With a summit that reaches 3,283 meters (10,771 feet), Shiveluch is one of the largest and most active volcanoes in Russia’s Kamchatka Peninsula. At least 60 large eruptions of Shiveluch have occurred during the past 10,000 years, making it the most vigorous volcano of the Kuril-Kamchatka volcanic arc.
On January 25, 2011, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’sTerra satellite detected a hot avalanche of volcanic debris—a pyroclastic flow—sliding down the south side of the volcano. This image shows the flow’s heat signature as measured in thermal infrared light. The white area at the lava dome is very hot, while the red areas on the edge of the flow are just warmer than the surrounding snow.
The hot trail of material descending to the south forms a large distributed deposit, indicating a recent collapse of the lava dome and formation of a large debris avalanche. According to the Global Volcanism Program, Shiveluch’s current eruptive period began in 1999.
References
- Global Volcanism Program. (n.d.) Shiveluch. Smithsonian Institution, National Museum of Natural History. Accessed February 10, 2011.
- Photojournal. (2011, January 27). NASA spacecraft captures fury of Russian volcano. NASA Jet Propulsion Laboratory. Accessed February 10, 2011.
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