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Volcano Hazard Program images.
A close-up of the spattering source on the floor of Pu‘u ‘Ō‘ō crater. A small spatter rampart has formed along the east side of the vent.
A close-up of the spattering source on the floor of Pu‘u ‘Ō‘ō crater. A small spatter rampart has formed along the east side of the vent.
The 1940 cone, just above center, pokes up above the otherwise relatively flat floor of Moku‘āweoweo - the summit caldera of Mauna Loa. Mauna Kea rises up in the background.
The 1940 cone, just above center, pokes up above the otherwise relatively flat floor of Moku‘āweoweo - the summit caldera of Mauna Loa. Mauna Kea rises up in the background.
View looking downslope at the various cones that dot Mauna Loa's Northeast Rift Zone. The edge of North Pit, on the north side of Moku‘āweoweo, is in the foreground.
View looking downslope at the various cones that dot Mauna Loa's Northeast Rift Zone. The edge of North Pit, on the north side of Moku‘āweoweo, is in the foreground.
Close-up of the 1949 cinder-and-spatter cone as seen from the floor of Moku‘āweoweo, Mauna Loa's summit caldera. pāhoehoe lava visible in the foreground (lower half of photo) was erupted in 1940. Beyond these flows, you can see pāhoehoe flows, spatter, and tephra erupted in 1949.
Close-up of the 1949 cinder-and-spatter cone as seen from the floor of Moku‘āweoweo, Mauna Loa's summit caldera. pāhoehoe lava visible in the foreground (lower half of photo) was erupted in 1940. Beyond these flows, you can see pāhoehoe flows, spatter, and tephra erupted in 1949.
Aerial view of Mauna Loa's upper northeast rift zone near the area where it intersects Moku‘āweoweo, the summit caldera. Pāhoehoe flows visible in the foreground were erupted in 1942. Distant steep cliffs (right background) are the west wall of the summit caldera.
Aerial view of Mauna Loa's upper northeast rift zone near the area where it intersects Moku‘āweoweo, the summit caldera. Pāhoehoe flows visible in the foreground were erupted in 1942. Distant steep cliffs (right background) are the west wall of the summit caldera.
A view of Moku‘āweoweo, the summit caldera of Mauna Loa, as seen from South Pit (looking to the north-northwest). An eruption in 1940 created the cinder-and-spatter cone visible on the caldera floor (right center). This cone, which is about 114 m (373 feet) high, is the largest cone at Mauna Loa's summit.
A view of Moku‘āweoweo, the summit caldera of Mauna Loa, as seen from South Pit (looking to the north-northwest). An eruption in 1940 created the cinder-and-spatter cone visible on the caldera floor (right center). This cone, which is about 114 m (373 feet) high, is the largest cone at Mauna Loa's summit.
An aerial view of the 1940 cinder-and-spatter cone on the floor of Mauna Loa's summit caldera as seen from the southeast. The west wall of the caldera (background) is about 170 m (560 feet) high. Most of the caldera floor around the cone is covered by lava flows erupted in 1984.
An aerial view of the 1940 cinder-and-spatter cone on the floor of Mauna Loa's summit caldera as seen from the southeast. The west wall of the caldera (background) is about 170 m (560 feet) high. Most of the caldera floor around the cone is covered by lava flows erupted in 1984.
This view of Mauna Loa's summit is looking toward the northeast. The east flank of Mauna Kea is to the left, and North Pit, on the northeast end of Moku‘āweoweo, is straight ahead.
This view of Mauna Loa's summit is looking toward the northeast. The east flank of Mauna Kea is to the left, and North Pit, on the northeast end of Moku‘āweoweo, is straight ahead.
The 1940 cinder-and-spatter cone as seen from the caldera floor looking to the southeast. This cone, which is about 114 m (373 feet) high, was built around the vent as lava spewed from it over a period of 134 days. The dark-colored pāhoehoe flows visible in the foreground were erupted in 1984.
The 1940 cinder-and-spatter cone as seen from the caldera floor looking to the southeast. This cone, which is about 114 m (373 feet) high, was built around the vent as lava spewed from it over a period of 134 days. The dark-colored pāhoehoe flows visible in the foreground were erupted in 1984.
A close-up view of the 1984 fissure that cut through the southwest side of Mauna Loa's 1940 vent cone. The crack on the right side of the cone is the 1984 fissure.
A close-up view of the 1984 fissure that cut through the southwest side of Mauna Loa's 1940 vent cone. The crack on the right side of the cone is the 1984 fissure.
Aerial view of the perched lava lake in Pu‘u ‘Ō‘ō crater. Small fluctuations in the lava lake level lead to frequent overflows. These serve to build the levee around the lake even higher, amplifying the perched appearance.
Aerial view of the perched lava lake in Pu‘u ‘Ō‘ō crater. Small fluctuations in the lava lake level lead to frequent overflows. These serve to build the levee around the lake even higher, amplifying the perched appearance.
View from just below the summit of Mauna Loa looking back down the Southwest Rift. The Sulfur Cone is the white area just above center frame. Pu‘u o Keokeo is the barely visible bump just above Sulfur Cone at the crest of the Southwest Rift.
View from just below the summit of Mauna Loa looking back down the Southwest Rift. The Sulfur Cone is the white area just above center frame. Pu‘u o Keokeo is the barely visible bump just above Sulfur Cone at the crest of the Southwest Rift.
View from above Mauna Loa's upper Northeast Rift Zone looking across an unnamed cone toward Mauna Kea.
View from above Mauna Loa's upper Northeast Rift Zone looking across an unnamed cone toward Mauna Kea.
The 1949 cinder-and-spatter cone (left) and 1940 spatter cone (right) as seen from the floor of Mauna Loa's summit caldera, looking to the southwest. Pāhoehoe flows in the foreground were erupted in 1984.
The 1949 cinder-and-spatter cone (left) and 1940 spatter cone (right) as seen from the floor of Mauna Loa's summit caldera, looking to the southwest. Pāhoehoe flows in the foreground were erupted in 1984.
USGS employees deploys a water conductivity/temperature/depth probe (AquaTroll) for a temporary study along the Madison River, Yellowstone.
USGS employees deploys a water conductivity/temperature/depth probe (AquaTroll) for a temporary study along the Madison River, Yellowstone.
The western Kamoamoa fountain-fed lava flows advanced over 1997 lavas (dark flow in foreground) with 1965 and 1968 lavas buried by Pu‘u ‘Ō‘ō cinder to the far left. Pu‘u ‘Ō‘ō is in the distant background.
The western Kamoamoa fountain-fed lava flows advanced over 1997 lavas (dark flow in foreground) with 1965 and 1968 lavas buried by Pu‘u ‘Ō‘ō cinder to the far left. Pu‘u ‘Ō‘ō is in the distant background.
A complex configuration has been in place deep within the vent cavity in Halema`uma`u crater. Lava upwells in the west portion of the vent floor (upper left of photograph), feeding the small, crusted, circular lava lake.
A complex configuration has been in place deep within the vent cavity in Halema`uma`u crater. Lava upwells in the west portion of the vent floor (upper left of photograph), feeding the small, crusted, circular lava lake.
A close-up of the swiftly moving lava stream, plunging into the lava lake.
A close-up of the swiftly moving lava stream, plunging into the lava lake.
Looking northwest at the lava pond on the floor of Pu‘u ‘Ō‘ō crater. At the time of the photograph, the level of the lava pond was about 3 m (10 ft) below the floor of the crater.
Looking northwest at the lava pond on the floor of Pu‘u ‘Ō‘ō crater. At the time of the photograph, the level of the lava pond was about 3 m (10 ft) below the floor of the crater.
An hour later, the lava had risen high enough to spill over the pond walls and expand across the crater floor.
An hour later, the lava had risen high enough to spill over the pond walls and expand across the crater floor.
After an intrusion on March 5, Pu‘u‘ō‘ō crater floor subsided for several hours. Hot incandescent crater walls were exposed as the floor dropped a total of 113 m (371 ft). Frequent rockfalls into the crater triggered red ash plumes. USGS photo taken by T. Orr on March 5, 2011, at 4:32 p.m.
After an intrusion on March 5, Pu‘u‘ō‘ō crater floor subsided for several hours. Hot incandescent crater walls were exposed as the floor dropped a total of 113 m (371 ft). Frequent rockfalls into the crater triggered red ash plumes. USGS photo taken by T. Orr on March 5, 2011, at 4:32 p.m.