Images

This map of Halema‘uma‘u at the summit of Kīlauea shows 20 m (66 ft) contour lines (dark gray) that mark locations of equal elevation above sea level (asl).

Seismic stations (white triangles) around Yellowstone Lake as seen on the online Geology of Yellowstone Map. Inset shows a seismogram for station YLA that can be accessed by clicking on the feature and following the “Seismogram” link in the popup box.

Cycles in Kīlauea's summit eruptive vigor were present on January 22 and 23, with the lava channel at Halema‘uma‘u's western fissure alternating between high and low flow rates over periods of 5-6 minutes. USGS photos by M. Patrick.

Active lava reached as far as the central lake in Halema‘uma‘u at Kīlauea's summit, on the east side of the main island, where crustal foundering was occasionally happening. USGS photo by M. Patrick.

Active lava was again limited to the western half of the lava lake in Halema‘uma‘u at Kīlauea Volcano's summit. The western vent remained active with cycles of eruptive vigor in the open channel lasting 5-6 minutes. USGS photo by M. Patrick.

Activity at the west vent within Halemaʻumaʻu crater on January 22 included frequent spattering from multiple locations and an open lava channel which drops 20 meters (65 feet) from its source to the lava lake surface.

Clamp-on ultrasonic flow meter measuring total flow on a pipe at a private well monitoring site.

Microscopic appearance of normal and melanistic skin in fish from Chesapeake Bay watershed.

Between overcast and rainy weather, HVO field crews took this photo at 3:34 p.m. HST on January 21, 2021, from the south side of Kīlauea's summit caldera. The photo shows Halema‘uma‘u's active west vent, which overflowed its tubed-over lower half at 2:51 p.m.

Photographs from a mallard duck (Anas platyrhynchos) found dead in Idaho, USA.  (A) The lungs are dark red and have multifocal 1-3 mm diameter white to tan nodules disseminated throughout (arrows).  (B) Cut section of the lung showing the nodules within the parenchyma (arrows).

Photomicrographs from a mallard duck (Anas platyrhynchos) found dead in Idaho, USA.  (A) Multiple granulomas (*) with eosinophilic necrotic centers efface the lung. H&E stain.  (B) Granulomas contain many degenerate heterophils and a few multinucleated giant cells (arrows). H&E stain.

This photo, taken at just after 6 p.m. HST on January 19, shows that the western fissure continues to send lava into Halemʻaumaʻu crater through an open channel into the lava lake. The western side of the lava lake has an incandescent surface, while the eastern portion is more crusted over.

The western fissure at Kīlauea's summit continues to send lava into Halemʻaumaʻu crater through an open channel into the lava lake. Around sunset on the evening of January 19, field crews observed a minor collapse event of the spatter rampart on its northern rim and the channel margins at 5:46 p.m. HST.

A close up of the southwest portion of the lava lake within Halema‘uma‘u, just south of the west fissure. The lava lake at Kīlauea's summit is perched, and is contained by a steep levee 2-3 meters (yards) high. USGS photo by M. Patrick.

A close up of the vent area at the western fissure within Halema‘uma‘u at Kīlauea's summit. The two main vents were exhibiting low fountaining while a small vent in the middle had sporadic, weak spattering. USGS photo by M. Patrick.

On the evening of January 17, the vent on the north side of the western fissure in Halema‘uma‘u at Kīlauea's summit activated and seemed to become the dominant vent overnight. This vent is the one on the right in this photo. The vent on the left, which was the dominant vent over the past week, seemed less energetic today. USGS photo by M. Patrick.

Sunlight interacts with volcanic gas from Kīlauea's summit lava lake and western fissure in this late afternoon view. The western fissure has built a spatter cone on the steep walls of Halema‘uma‘u, with lava spilling into the active lake, which forms the lower right portion of the photo.

A closer view of the low fountaining at the western fissure in  Halema‘uma‘u at Kīlauea's summit. The rim of the cone is built from accumulated deposits of spatter, and large chunks of the cone rim were observed to collapse from time to time. USGS photo by M. Patrick

Low fountaining continues at the western fissure, supplying lava to the lava lake in Halema‘uma‘u crater, at the summit of Kīlauea. The vent has formed a spatter cone around the fountaining, with lava spilling into an open channel that plunges into the lake.

Drilling through ice on the Green River.

Mudpot located in the Mud Volcano thermal area of Yellowstone National Park.  This type of thermal feature indicates an acid-sulfate system.