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Volcano Hazard Program images.
Only small amounts of sulfur dioxide (SO2) and hydrogen sulfide (H2S) are currently being released from Kīlauea, but they chemically react with each other (oxidation-reduction reaction) to form the bright yellow sulfur deposits visible on the crater walls within Halema‘uma‘u.
Only small amounts of sulfur dioxide (SO2) and hydrogen sulfide (H2S) are currently being released from Kīlauea, but they chemically react with each other (oxidation-reduction reaction) to form the bright yellow sulfur deposits visible on the crater walls within Halema‘uma‘u.
Microprobe laboratory in Menlo Park, California.
Argon geochronology lab in Menlo Park, California.
Argon geochronology lab in Menlo Park, California.
A scientist takes a gravity reading at a station located on the down-dropped block of Kīlauea caldera, which subsided as an intact structure, while a second gravity instrument (foreground) records data. Many of the preexisting gravity stations, which have been measured for years, survived Kīlauea's 2018 summit collapse.
A scientist takes a gravity reading at a station located on the down-dropped block of Kīlauea caldera, which subsided as an intact structure, while a second gravity instrument (foreground) records data. Many of the preexisting gravity stations, which have been measured for years, survived Kīlauea's 2018 summit collapse.
USGS Hawaiian Volcano Observatory staff, September 2018.
USGS Hawaiian Volcano Observatory staff, September 2018.
This aerial view of the western part of Kīlauea Volcano's caldera was taken on August 6, 2018. The down-dropped block is faulted about 120 m (400 feet) below the caldera floor. Many 19th-century lava flows are exposed in the fault scarps. Halema‘uma‘u (not visible) is to the left of this photo. USGS photo by D.Swanson.
This aerial view of the western part of Kīlauea Volcano's caldera was taken on August 6, 2018. The down-dropped block is faulted about 120 m (400 feet) below the caldera floor. Many 19th-century lava flows are exposed in the fault scarps. Halema‘uma‘u (not visible) is to the left of this photo. USGS photo by D.Swanson.
New thermal feature beneath the boardwalk on Geyser Hill, Upper Geyser Basin. Boards removed for better observation. Pump Geyser is mound at end of boardwalk. Old Faithful Inn in distance.
New thermal feature beneath the boardwalk on Geyser Hill, Upper Geyser Basin. Boards removed for better observation. Pump Geyser is mound at end of boardwalk. Old Faithful Inn in distance.
Mules loaded with sampling equipment and supplies for a mission to collect gas and thermal water samples from the Bechler River area in the southwest part of Yellowstone National Park.
Mules loaded with sampling equipment and supplies for a mission to collect gas and thermal water samples from the Bechler River area in the southwest part of Yellowstone National Park.
An unnamed but charismatic thermal feature alongside Ferris Fork, near the Bechler River. The center of the pool is roiling with gas bubbles, but not boiling! The pool is only about 180 degrees F (81 degrees C), and all the gas is bubbling up from underground.
An unnamed but charismatic thermal feature alongside Ferris Fork, near the Bechler River. The center of the pool is roiling with gas bubbles, but not boiling! The pool is only about 180 degrees F (81 degrees C), and all the gas is bubbling up from underground.
Following the draining of magma from Pu‘u ‘Ō‘ō on April 30, 2018, the crater was roughly 356 meters (1168 feet) deep. The upper part of the crater was flaring, with the deepest portion a narrower cylindrical shaft.
Following the draining of magma from Pu‘u ‘Ō‘ō on April 30, 2018, the crater was roughly 356 meters (1168 feet) deep. The upper part of the crater was flaring, with the deepest portion a narrower cylindrical shaft.
Explosive eruption columns of ash rising from Halema‘uma‘u at 11:15 a.m. on May 18, 1924 (top) and at 11:05 a.m. on May 15, 2018 (bottom) look similar.
Explosive eruption columns of ash rising from Halema‘uma‘u at 11:15 a.m. on May 18, 1924 (top) and at 11:05 a.m. on May 15, 2018 (bottom) look similar.
The video was taken during an overflight of Pu‘u ‘Ō‘ō crater on Kīlauea's middle East Rift Zone. No major changes were observed, but the crater shape continues to change due to continued rockfalls.
The video was taken during an overflight of Pu‘u ‘Ō‘ō crater on Kīlauea's middle East Rift Zone. No major changes were observed, but the crater shape continues to change due to continued rockfalls.
Landsat-8 nighttime thermal infrared image from April 2017 showing the Tern Lake area. In Yellowstone, temperatures are extremely cold at night in the winter, and most lakes are frozen (dark pixels). West Tern Lake seems to be thawing here - perhaps it receives some thermal waters from nearby hot springs.
Landsat-8 nighttime thermal infrared image from April 2017 showing the Tern Lake area. In Yellowstone, temperatures are extremely cold at night in the winter, and most lakes are frozen (dark pixels). West Tern Lake seems to be thawing here - perhaps it receives some thermal waters from nearby hot springs.
View into Halema‘uma‘u from the west rim of Kīlauea's summit caldera. USGS photo: J. Kauahikaua, 03 March 2019
View into Halema‘uma‘u from the west rim of Kīlauea's summit caldera. USGS photo: J. Kauahikaua, 03 March 2019
Aerial view due south of the Mono Lake-Long Valley volcanic region. Inset map shows locations of latest Pleistocene–Holocene silicic magmatic centers relative to Long Valley caldera. Rhyolites of the Mono–Inyo chain are shown in pink, and the dacitic–rhyodacitic Mammoth Mountain dome complex is shown in blue. U.S.
Aerial view due south of the Mono Lake-Long Valley volcanic region. Inset map shows locations of latest Pleistocene–Holocene silicic magmatic centers relative to Long Valley caldera. Rhyolites of the Mono–Inyo chain are shown in pink, and the dacitic–rhyodacitic Mammoth Mountain dome complex is shown in blue. U.S.
Huckleberry Ridge Tuff deposit exposed on Mt. Everts, near the northern boundary of Yellowstone National Park. The deposit was created by ash falling from the plume early in the eruption sequence, 2.08 million years ago. Photo by Madison Myers, Montana State University.
Huckleberry Ridge Tuff deposit exposed on Mt. Everts, near the northern boundary of Yellowstone National Park. The deposit was created by ash falling from the plume early in the eruption sequence, 2.08 million years ago. Photo by Madison Myers, Montana State University.
This ‘a‘ā flow erupted from fissure 8 on Kīlauea Volcano's lower East Rift Zone on June 1, 2018, shows how the interior of a lava flow remains incandescently hot even though surface cooling forms a crust of solid rubble.
This ‘a‘ā flow erupted from fissure 8 on Kīlauea Volcano's lower East Rift Zone on June 1, 2018, shows how the interior of a lava flow remains incandescently hot even though surface cooling forms a crust of solid rubble.
A USGS pilot and Hawaiian Volcano Observatory gas geochemist prepare to conduct a test flight of an unmanned aerial system (UAS) on Kīlauea Volcano in November 2018. This UAS was outfitted with a prototype miniaturized multi-gas sensor for the detection of volcanic gases emitted by Kīlauea, including sulfur dioxide and carbon dioxide.
A USGS pilot and Hawaiian Volcano Observatory gas geochemist prepare to conduct a test flight of an unmanned aerial system (UAS) on Kīlauea Volcano in November 2018. This UAS was outfitted with a prototype miniaturized multi-gas sensor for the detection of volcanic gases emitted by Kīlauea, including sulfur dioxide and carbon dioxide.
Dragon’s Mouth in the Mud Volcano Area of Yellowstone National Park.
Dragon’s Mouth in the Mud Volcano Area of Yellowstone National Park.
Many of the earthquakes in Hawaii that extend offshore and up the island chain are due to plate bending, or flexure. The upper panel shows magnitude-5 and greater earthquakes since 1861, with some notable events labeled.
Many of the earthquakes in Hawaii that extend offshore and up the island chain are due to plate bending, or flexure. The upper panel shows magnitude-5 and greater earthquakes since 1861, with some notable events labeled.
A sensor data logger recovered from the floor of Yellowstone Lake in the Deep Hole area in 2018 shows signs of melting due to unexpectedly high temperatures in sediments up to ~3 ft (1 m) away from an active hydrothermal vent. Image acquired by the Global Foundation for Ocean Exploration ROV Yogi on August 4, 2018.
A sensor data logger recovered from the floor of Yellowstone Lake in the Deep Hole area in 2018 shows signs of melting due to unexpectedly high temperatures in sediments up to ~3 ft (1 m) away from an active hydrothermal vent. Image acquired by the Global Foundation for Ocean Exploration ROV Yogi on August 4, 2018.