...
| Image | Details | Volcanoes | Keywords |
 |
| Caption: | Thin section of lava from the Cobweb Lava Flow, erupted from Aniakchak Peak ~400 years ago. The name "Cobweb" comes from B.R. Hubbard (1932), who called it the "Avernian Cobweb."
According to Wes Hildreth (USGS), "The poisonous vapors of Avernus, Italy, killed many birds, and Hubbard witnessed the same at Aniakchak, which seems why he adopted this name."
The video shows 3-5 mm wide aggregates of crystals suspended in a finer-grained groundmass of tiny crystals. The minerals under the cross-polarized light are plagioclase (gray/white), clinopyroxene (blues/reds/oranges), orthopyroxene (pale yellow-gray), and FeTi oxide minerals like magnetite and ilmenite (black).
Most of the tiny minerals in the groundmass are plagioclase. They formed when the magma ascended to the surface and solidified as a lava. The larger minerals formed under higher temperatures (~850 C) deep underground. |
| Date: | October 27, 2020 12:00 AM |
| Photographer: | Browne, Brandon |
| Aniakchak | Lava flow |
 |
| Caption: | A WorldView-1 satellite image taken on October 26, 2020 (UTC; October 25 local time) shows the typical minor steam plume from the crater lake at the summit of Korovin Volcano. Imagery is panchromatic grayscale. |
| Date: | October 26, 2020 1:53 AM |
| Photographer: | Dietterich, Hannah |
| Korovin | |
 |
| Caption: | Sulfur dioxide (SO2) is a common volcanic gas that is released from magma within Earth’s upper crust. While SO2 is commonly released from Alaska’s active volcanoes, including Korovin, a recent increase in satellite detections of SO2 emissions from Korovin may be a sign of volcanic unrest. In sufficient quantity, SO2 can be readily measured from space due to its low quantity in background air. This image shows SO2 emissions from Korovin that were detected by the TROPOMI satellite sensor on October 26, 2020. In this image, the warmer colors represent larger quantities of SO2 measured within a column of atmosphere. These SO2 column densities are reported in Dobson Units (DU) where 1 DU = 2.85 x 10^-2 g of SO2/m^2. AVO will continue to monitor satellite detections of SO2 from Korovin, in combination with other volcano monitoring techniques, to evaluate ongoing activity at Korovin volcano. |
| Date: | October 26, 2020 12:00 AM |
| Photographer: | Lopez, Taryn |
| Korovin | Gas, Volcano |
 |
| Caption: | Clear satellite views in Planet Labs imagery on October 19, 2020 show the typical minor steam plume from the crater lake at Korovin. This image also shows the nearby volcanoes to the south, Konia and Kliuchef. Their summit regions are snow covered with no visible fumaroles or other signs of activity. |
| Date: | October 19, 2020 7:27 PM |
| Photographer: | Dietterich, Hannah |
| Atka, Korovin | |
 |
| Caption: | Partly cloudy Worldview-2 image of Semisopochnoi with the North Cerebus crater rim just visible between clouds. The crater itself is filled with thick steam or clouds, but a narrow and diffuse possible gas plume is visible accross the image front North Cerebus to the east, consistent with westerly winds. Image is visible "RGB" bands. |
| Date: | October 18, 2020 11:16 PM |
| Photographer: | Loewen, Matt |
| Semisopochnoi | Steam |
 |
| Caption: | Kasatochi as seen from Alaska Airlines flight from Adak. Photo by pilot Steve Rhodes. |
| Date: | October 18, 2020 6:41 PM |
| Photographer: | Rhodes, Steve |
| Kasatochi | |
 |
| Caption: | Great Sitkin as seen from Alaska Airlines flight from Adak. Photo by pilot Steve Rhodes. |
| Date: | October 18, 2020 6:36 PM |
| Photographer: | Rhodes, Steve |
| Great Sitkin | |
 |
| Caption: | Iliamna Volcano and summit fumaroles. The Tuxedni glacier is visible on the left side of the image, as well as Redoubt Volcano in the background. |
| Date: | October 15, 2020 3:24 PM |
| Photographer: | Lyons, John |
| Iliamna, Redoubt | Fumarolic activity, Glacier, Stratovolcano, Volcano |
 |
| Caption: | The fumarole fields on the eastern flank of Iliamna Volcano. |
| Date: | October 15, 2020 2:59 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Steam, Stratovolcano, Volcano |
 |
| Caption: | Iliamna Volcano and summit fumaroles. View is to the northeast. Redoubt Volcano and Cook Inlet are visible in the background. |
| Date: | October 15, 2020 2:53 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Steam, Stratovolcano, Volcano |
 |
| Caption: | The southwestern flank of Iliamna Volcano with Cook Inlet and Redoubt Volcano in the background. |
| Date: | October 15, 2020 2:44 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | Iliamna Volcano summit and the more northerly of the two fumarole fields. |
| Date: | October 15, 2020 2:40 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | The more northerly fumarole field on the eastern face of Iliamna Volcano's summit. |
| Date: | October 15, 2020 2:40 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | The more southern fumarole field on the steep eastern face of Iliamna Volcano's summit. |
| Date: | October 15, 2020 2:40 PM |
| Photographer: | Lyons, John |
| Iliamna | Fumarolic activity, Steam, Stratovolcano, Volcano |
 |
| Caption: | The eastern side of Redoubt Volcano on a bluebird fall day. |
| Date: | October 15, 2020 11:44 AM |
| Photographer: | Lyons, John |
| Redoubt | Stratovolcano, Volcano |
 |
| Caption: | Summit of Redoubt Volcano and the 2009 dome. View is to the southwest. Iliamna Volcano is the prominent peak in the background. |
| Date: | October 15, 2020 11:36 AM |
| Photographer: | Lyons, John |
| Iliamna, Redoubt | Dome, Stratovolcano, Volcano |
 |
| Caption: | Redoubt Volcano summit and 2009 dome. View is to the west with the Chigmit Mountains of Lake Clark National Park in the background. |
| Date: | October 15, 2020 11:35 AM |
| Photographer: | Lyons, John |
| Redoubt | Dome, Stratovolcano, Volcano |
 |
| Caption: | View to the northeast of the Redoubt Volcano summit and still-steaming 2009 dome. |
| Date: | October 15, 2020 11:35 AM |
| Photographer: | Lyons, John |
| Redoubt | Dome, Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | Site ILW on Iliamna |
| Date: | October 15, 2020 11:25 AM |
| Photographer: | Herstand, Malcolm |
| Iliamna | |
 |
| Caption: | NSF-AVO Postdoc Cassandra Smith plumbing calibration gases (SO2 and H2S) into the MultiGAS instrument during the fall 2020 Cook Inlet gas sampling flight. |
| Date: | October 15, 2020 11:21 AM |
| Photographer: | Lyons, John |
| Iliamna, Redoubt, Spurr | Fumarolic activity, People in action, Stratovolcano |
 |
| Caption: | Fumarolic activity from the summit crater of Mount Spurr observed during the fall 2020 gas flight. |
| Date: | October 15, 2020 11:18 AM |
| Photographer: | Lyons, John |
| Array | Caldera/crater, Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | Crater Peak of Mount Spurr observed during the fall 2020 gas flight. |
| Date: | October 15, 2020 11:16 AM |
| Photographer: | Lyons, John |
| Spurr | Caldera/crater, Stratovolcano, Volcano |
 |
| Caption: | Mount Spurr summit observed during the fall 2020 gas flight. |
| Date: | October 15, 2020 10:54 AM |
| Photographer: | Lyons, John |
| Array | Fumarolic activity, Stratovolcano, Volcano |
 |
| Caption: | Summit of Mount Spurr with weak fumarole observed during the fall 2020 gas flight. |
| Date: | October 15, 2020 10:42 AM |
| Photographer: | Lyons, John |
| Spurr | Caldera/crater, Fumarolic activity, Glacier, Stratovolcano, Volcano |
 |
| Caption: | Iliamna from North |
| Date: | October 15, 2020 10:13 AM |
| Photographer: | Herstand, Malcolm |
| Iliamna | |
...
Summary
Color Code Definitions
Webcams 
Akutan AKSD
Webicorders 
RSAM 
Korovin
Volcano List
About Alaska's Volcanoes
Eruption Search
Operations
Response
Staff
Fields of Study
Glossary
Recent Images
Browse Images
