Images

Kīlauea Volcano's east Lae‘apuki lava delta pictured hours before it collapsed into the sea over a 90-minute period. White plume marks location of lava entering sea fed by a lava tube within delta.

Loowit Falls flows north out of Mount St. Helens crater. White building in upper right corner is the Loowit gage house, which contains an Acoustic Flow Monitor.

pāhoehoe lava spilling over sea cliff on south coast of Kīlauea Volcano starts to build a new lava delta. Only three days old, the delta grows slowly as lava spreads over fragmented debris and flows that have accumulated on the steep submarine slope.

Explosive interaction between lava and seawater blasts a tephra jet consisting of steam, hot water, black tephra, and molten fragments into the air. Such explosions are typically directed toward the sea, but many explosions also send a shower of lava more than 10 to 20 m (33 to 66 ft) inland.

Active lava delta at East Lae‘apuki on the south coast of Kīlauea Volcano. White gas plume (right) marks location of lava entering the sea through a lava tube whose location is shown by blueish fume (left and center). In early August 2005, the delta encompassed an area of about 12 hectares (30 acres).

Scientists maintain an Acoustic Flow Monitor (AMF) at Mount St. Helens, Washington. It detects ground movement associated with lahars.

A VHF radio receiving tower is set up on the slopes of Mauna Kea volcano on Hawai‘i Island, Hawai‘i. This setup allowed researchers to track radio tagged palila over large areas to determine where they were spending their time. 

Crater Creek warm springs, Mount Spurr Volcano. Chris Waythomas measuring temperature, pH, and conductivity.

Fissure 8 and the upper lava channel, as viewed during the early morning helicopter overflight on July 22, 2018.

South-facing aerial view of Mount St. Helens with Mount Hood (left) and Mount Jefferson (right) on the horizon. June 8, 2005.

USGS scientists measuring temperature in a deep borehole in Long Valley Caldera with the Sierra Nevada mountains in the background.

Park Butte Fire Lookout sits above a lava flow that erupted around 716,000 years ago near Mount Baker, Washington.

Ash collection from east Crater Glacier on Mount St. Helens with a dredge attached to a helicopter cable. Ash is analyzed to help scientists understand eruption characteristics.

Fumaroles steaming within Sherman Crater, Mount Baker, Washington.

The May 18, 1980 eruption of Mount St. Helens began with an enormous landslide that slammed into Spirit Lake, blocking its natural outlet and raising the lake level by 197 feet.

Crater Glacier (cracked surface in center left foreground) and whaleback-shaped lava spine within dome complex of Mount St. Helens' crater. Glacier is squeezed and over thickened. February 22, 2006

Mount Bachelor viewed from South Sister, Oregon.

Broken pillow lavas, colored red by iron oxide, inside Vailulu'u crater. 

Aerial view, Mount St. Helens' crater and dome, as seen from the northeast. Note dusting of ash on Mount St. Helens' flank, left near rim.

Aerial view, Mount St. Helens' crater and dome, as seen from the northeast.

Whaleback structure (center) of dome withn Mount St. Helens' crater. Dome is crumbling to right and glacier is uplifted to the left, view from the north. January 30, 2005.