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Volcano Hazard Program images.
Crater Lake panorama seen from the lake's southern shore. Wizard Island is cone in western portion of lake. Oregon
Crater Lake panorama seen from the lake's southern shore. Wizard Island is cone in western portion of lake. Oregon
On July 6, 1975, eruptive fissures opened along Mauna Loa
On July 6, 1975, eruptive fissures opened along Mauna Loa
Lava fountains up to 20 m (65 ft) high erupted from fissures on the north flank of Mauna Loa early Sunday morning, July 6, 1975. USGS photo.
Lava fountains up to 20 m (65 ft) high erupted from fissures on the north flank of Mauna Loa early Sunday morning, July 6, 1975. USGS photo.
This thermal image shows the view of the Halema`uma`u vent from today's overflight. The kidney-shaped lava pond, about 90 meters long, is deep within the vent cavity. The mostly-crusted lava migrates from the north (right in this photo), where it upwells from depth, to the south, where is sinks back into the conduit.
This thermal image shows the view of the Halema`uma`u vent from today's overflight. The kidney-shaped lava pond, about 90 meters long, is deep within the vent cavity. The mostly-crusted lava migrates from the north (right in this photo), where it upwells from depth, to the south, where is sinks back into the conduit.
Lava flows are once again nearing the County viewing area at the end of Highway 130. The flow front is about one kilometer (0.6 mi) away, burning small patches of vegetation in its path.
Lava flows are once again nearing the County viewing area at the end of Highway 130. The flow front is about one kilometer (0.6 mi) away, burning small patches of vegetation in its path.
Geologist taking a sample from a recently formed skylight on the Quarry flow lava tube. Samples collected directly from the lava tube are usually the best samples for chemical analysis.
Geologist taking a sample from a recently formed skylight on the Quarry flow lava tube. Samples collected directly from the lava tube are usually the best samples for chemical analysis.
Map showing the extent of the July 2007 eruption flow field relative to surrounding communities. Light red is the extent of the July 2007 eruption flow field. Reddish-brown is the extent of the currently-active Quarry flow as of July 8, 2010, while bright red shows the flow field expansion of the Quarry flow mapped by HVO geologists between July 8 and 14.
Map showing the extent of the July 2007 eruption flow field relative to surrounding communities. Light red is the extent of the July 2007 eruption flow field. Reddish-brown is the extent of the currently-active Quarry flow as of July 8, 2010, while bright red shows the flow field expansion of the Quarry flow mapped by HVO geologists between July 8 and 14.
This image is a composite of a normal photograph and a thermal image, and shows the currently active flows coming down the pali towards the ocean. The active flow areas are shown as white and yellow, while older, cooler flows are shown by purple hues.
This image is a composite of a normal photograph and a thermal image, and shows the currently active flows coming down the pali towards the ocean. The active flow areas are shown as white and yellow, while older, cooler flows are shown by purple hues.
The lava pond resides deep within the vent cavity in Halema‘uma‘u, at a depth of about 180 m (200 yards). Photograph taken from the former Halema‘uma‘u Overlook on June 20, 2010.
The lava pond resides deep within the vent cavity in Halema‘uma‘u, at a depth of about 180 m (200 yards). Photograph taken from the former Halema‘uma‘u Overlook on June 20, 2010.
An aerial photo looking directly into a skylight that formed in the last 24 hours. This skylight is located at the top of one of the rootless shields on the upper flow field.
An aerial photo looking directly into a skylight that formed in the last 24 hours. This skylight is located at the top of one of the rootless shields on the upper flow field.
Geologist changing the data card from the time-lapse camera on the north rim of Pu'u 'Ö'ö cone.
Geologist changing the data card from the time-lapse camera on the north rim of Pu'u 'Ö'ö cone.
Rootless shields grow both in breadth and height through the accumulation of repeated overflows from the summits of the shields. In this photo, a stream of lava is flowing southward down the flank of this emergent shield.
Rootless shields grow both in breadth and height through the accumulation of repeated overflows from the summits of the shields. In this photo, a stream of lava is flowing southward down the flank of this emergent shield.
View looking southeast along the fuming trace of the TEB tube system. The growing rootless shield field is in the background just above and to the left of center frame. The low, rounded shape of the shields--especially the shield in shadow to the left--are evident in this photo.
View looking southeast along the fuming trace of the TEB tube system. The growing rootless shield field is in the background just above and to the left of center frame. The low, rounded shape of the shields--especially the shield in shadow to the left--are evident in this photo.
View looking the opposite direction (toward the northwest) with the rootless shields field crossing the image just above center. The low rounded shield shape is not apparent at this slightly steeper angle. The terminus of the active flows is just above the lower right side of the photo.
View looking the opposite direction (toward the northwest) with the rootless shields field crossing the image just above center. The low rounded shield shape is not apparent at this slightly steeper angle. The terminus of the active flows is just above the lower right side of the photo.
Rootless shields, when active, are often topped by a lava pond, as seen here.
Rootless shields, when active, are often topped by a lava pond, as seen here.
Seismic station VALT in Mount St. Helens crater, view toward the south.
Seismic station VALT in Mount St. Helens crater, view toward the south.
Activity on the active flow field has been dominated by rootless lava shield construction for the past several weeks (Pu`u `Ō `ō). The main shield, seen here, is topped by a lava pond that feeds overflows down the sides of the shield. Successive overflows slowly build up the height of the shields.
Activity on the active flow field has been dominated by rootless lava shield construction for the past several weeks (Pu`u `Ō `ō). The main shield, seen here, is topped by a lava pond that feeds overflows down the sides of the shield. Successive overflows slowly build up the height of the shields.
A close-up view of the top of the main rootless lava shield at Pu`u `Ō `ō. The lava pond at the top of the shield is roughly 100 meters (yards) across.
A close-up view of the top of the main rootless lava shield at Pu`u `Ō `ō. The lava pond at the top of the shield is roughly 100 meters (yards) across.
This photo, taken at the northern base of the main rootless lava shield (Pu`u `Ō `ō), shows lava flowing down the flank of the shield.
This photo, taken at the northern base of the main rootless lava shield (Pu`u `Ō `ō), shows lava flowing down the flank of the shield.
This aerial view of the main rootless lava shield (at Pu`u `Ō `ō) shows the low, domed shape of this type of flow field feature. Sometimes, the flank of a rootless shield will fail, suddenly releasing the lava stored within and feeding fast moving 'a'ā flows.
This aerial view of the main rootless lava shield (at Pu`u `Ō `ō) shows the low, domed shape of this type of flow field feature. Sometimes, the flank of a rootless shield will fail, suddenly releasing the lava stored within and feeding fast moving 'a'ā flows.
Cross section through the trunk of a lodgepole pine tree from Cooking Hillside near Mud Volcano, Yellowstone National Park. The earliest date for this tree is 1916 and it died in 1990. Spongy white-gray areas are foam insulation that was injected into the sample to reinforce the structure of the wood.
Cross section through the trunk of a lodgepole pine tree from Cooking Hillside near Mud Volcano, Yellowstone National Park. The earliest date for this tree is 1916 and it died in 1990. Spongy white-gray areas are foam insulation that was injected into the sample to reinforce the structure of the wood.