Images

Mount Shasta, a steep-sided Cascade Range stratovolcano in Northern California, looms above Little Glass Mountain, a thick obsidian flow erupted from the Medicine Lake shield volcano about 1,000 years ago. These are just two of the young volcanic areas monitored by the USGS California Volcano Observatory. USGS photo.

Department of Interior UAS pilots from left to right – Elizabeth Pendleton (USGS, Woods Hole, MA), Colin Milone (Office of Aviation Services, AK), John Vogel (USGS; Flagstaff, AZ), Sandy Brosnahan (USGS, Woods Hole, MA), Brandon Forbes (USGS; Tucson, AZ), Chris Holmquist-Johnson (USGS; Fort Collins, CO),&nb

Ambae Island is in the northern Vanuatu archipelago (Figure A, courtesy of NASA) and hosts a nested caldera at its summit. A temporary seismic-acoustic array was deployed beginning July 2018 (yellow squares). Local airports are marked by the red squares.

Plot of ground motion as recorded by a GPS station at Kīlauea's summit (red) and the Pu‘u ‘Ō‘ō vent (blue) for the 8 months leading up to the 2018 eruption. Note the sharp increase indicating pressurization beginning in March. Image shows an aerial view of Halema‘uma‘u crater and the actively overflowing lava lake on April 23, 2018. 

An aerial view of the prominent 1940 cinder-and-spatter cone on the floor of Mauna Loa's summit caldera. The cone, about 100 m (330 ft) high, was built during a 134-day-long eruption that began on April 7, 1940. Most of the caldera floor around the cone is covered by lava flows erupted in 1984.

High-resolution, bare-earth, airborne light detection and ranging (LiDAR) image, looking obliquely northwest into Rocky Ridge.

A view into the center of Pu‘u ‘Ō‘ō. Collapses on the crater walls have enlarged sections of the crater and filled the bottom of the crater with rockfall debris. The deepest portion of the crater is about 286 m (938 ft) below the crater floor that existed prior to the collapse on April 30, 2018. Steam rises from the loose rock on the crater floor. USGS image by F.

On May 7, 2019, field crews visited a telemetry hub on the rim of Pu‘u ‘Ō‘ō to assess damage after a small collapse on May 1. During the overflight, photos and observations were made of the Pu‘u ‘Ō‘ō crater. The crater walls expose a clear sequence of lava flows and cinder that built the cone in the early 1980s. USGS image by F. Younger.

This lava fountain, which erupted on September 6, 1969, during the Mauna Ulu eruption, was about 540 m (1770 ft) tall. The tephra cone, eventually named Mauna Ulu, can be seen in the fallout area (right of the fountains. in middle of image). It is now a 121 m (397 ft) tall lava shield in Hawai‘i Volcanoes National Park.

Teaching Through Technology (T3) Alliance students in the University of Hawai‘i at Hilo Upward Bound summer program install a large display showing measurements from their air-quality monitoring station outside the Pāhoa Community Center, which was used as a temporary shelter for displaced residents from Kīlauea Volcano's 2018 eruption.

Good weather provided clear views of Halema‘uma‘u during a routine visit to the webcam on the northwest rim of the caldera.

Students from the Teaching Through Technology (T3) Alliance, University of Hawai‘i at Hilo Upward Bound summer program, install an air-quality monitoring station outside the Dragon's Eye Learning Center on Papaya Farms Road. Photo courtesy of Adam Low, T3 Alliance.

HVO geologist Matthew Patrick being interviewed on the Kīlauea lava-flow field for a documentary about Hawaiian volcanism. Growing lava delta (left background) steaming at the point of ocean entry.

William Clark's 1814 map, indicating the route of John Colter during the winter of 1807-1808. (Library of Congress, Geography and Map Division, Washington, D.C.)

Amphitheater Mountain and Soda Butte Creek viewed from the northeast entrance road. National Park Service photo by Jacob Frank, June 29, 2017.

A field team from the USGS Cascades Volcano Observatory discuss station maintenance plans on the north side of Mount St. Helens, Washington. Pictured in the center of the crater is a steaming lava dome from the 2004-08 eruption, and the fractured surface of Crater Glacier emerging from the gap on the north flank.  

An HVO geologist walks along the summit trail, with Mauna Kea in the background.

HVO geologists made a routine visit to the webcam monitoring Halema‘uma‘u. No changes were observed in the pit, but views were hampered by poor weather and thick fog.

Serapeum, a Roman Marketplace in Pozzuoli, Italy, records deformation of Campi Flegrei caldera over two millennia. It was built above sea level about 2000 years ago, but mollusk borings on the large marble columns indicate that it subsided by 7 meters (23 feet) below sea level before being uplifted above sea level once more in the past several hundred years.

Map showing the minimum area covered by volcanic ash from eruptions of Valles Ca

HVO staff visited the summit of Mauna Loa on foot to repair the webcam. The weather was perfectly clear, and views of the caldera floor showed nothing unusual.