Mount Veniaminof is a glacier-topped volcano located in southern Alaska. On September 3, 2018, the Alaska Volcano Observatory raised its Volcano Alert Level and Aviation Color Code at Veniaminiof from green, designating normal, to yellow, an “advisory,” due to seismic activity. The next day, the agency raised its alert level to orange, a “watch” level, because of low-level ash emissions observed on webcams. The color-code level has since been reduced to yellow.
Miller et al. (1998) provide a description of the mountain: “Mount Veniaminof is a broad central mountain, 35 [kilometers] wide at the base, truncated by a spectacular steep-walled summit caldera 8 by 11 km in diameter. The caldera is filled by an ice field that ranges in elevation from approximately 1750 to 2000 [meters]; ice obscures the south rim of the caldera and covers 220 square km of the south flank of the volcano. Alpine glaciers descend from the caldera through gaps on the west and north sides of the rim and other alpine glaciers occupy valleys on the north, east, and west-facing slopes of the mountain. In the western part of the caldera, an active intracaldera cone with a small summit crater has an elevation of 2156 m, approximately 330 m above the surrounding ice field. The rim of a larger but more subdued intracaldera cone protrudes just above the ice surface in the northern part of the caldera; based on limited exposure and physiographic features, it may have a summit crater as much as 2.5 km in diameter.”
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