Images

A burst tumulus near Kamokuna, which is a lava delta where Puʻu ʻŌʻō flows enter the Pacific Ocean. Tumuli can burst when the influx of lava is rapid compared to the rate at which the crust is thickening by cooling. In these cases the pressure driving the lava is significantly greater than the weight of the overlying crust.

Subsequent flows have fed lava into the skylight. A stationary crust is formed on margins of the flowing lava within the tube at this location, probably due to the loss of heat through the skylight.

A “drippy” tumulus near Kamokuna, which is a lava delta where Puʻu ʻŌʻō flows enter the Pacific Ocean. These tumuli form when the upwelling lava has a steady pressure and rate of movement, so the upper crust does not break apart. Instead, the lava slowly squeezes out.

A cinder cone within the Mount Aso caldera, located on Kyushu Island, Japan. The caldera contains several cinder cones and stratovolcanoes.

Rubens coil inside the Rock Magnetics Laboratory on the USGS Menlo Park campus. The function of the Rubens coil is to cancel the earth's magnetic field for thermal demagnetization of core samples. It is constructed of nonmagnetic materials and the control unit is place far enough away from the instrument to avoid interference from its metal components.

Flat-topped tumulus on Mauna Ulu lavas along Chain of Craters Road, Hawaii. Tumuli are just one end-member of a wide range of features formed by inflation of lava flows. A flat-topped tumulus is a half-way between a classic tumulus and a "lava-rise" or inflation plateau.

Flat-topped tumulus on Mauna Ulu lavas along Chain of Craters Road, Hawaii. Tumuli are just one end-member of a wide range of features formed by inflation of lava flows. A flat-topped tumulus is a half-way between a classic tumulus and a "lava-rise" or inflation plateau.

A classic marine tide pool environment among some of the black lava rocks found on the southern shore of Maui in the Hawaiian islands.

Rainstorm over Kauai mountains and Hanalei Bay at the North Shore of Kauai.

A classic marine tide pool environment among some of the black lava rocks found on the southern shore of Maui in the Hawaiian islands.

USGS scientists conduct research on the remote, rugged 'Alakai Plateau of Kaua'i.

Samples of welded scoria. Scoria is another word for the ‘cinders’ that make up volcanic cinder cones. Roza Member, Columbia River Basalt Group. Southeast of Winona, WA.

A detail of a pahoehoe lobe at the top of a tumulus. The upper crust that is lifted up during the formation of a tumulus is typically quite vesicular (has lots of bubbled trapped in it). Roza Formation, Columbia River Basalt Group. Southwest of Quincy, WA.

Draped scoria cone; partially collapsed. Roza Member, Columbia River Basalt Group. East of Winona, WA.

During the past century, the grassland has continued to become more shrubby with increases in such plants as broom snakeweed and velvet mesquite. The mesquite, occurring here near the upper limits of its range, has remained short, probably as the result of catastrophic freezes that have visited the area. Bush muhly is found beneath some of the mesquites.

A skylight near Pulama Pali, which is the slope where flows from Pu’u O’o make their way toward the sea. Here, the skylight allows one to see where the lava tube is splitting into two branches.

Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure.

Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure.

Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure.

Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure.

Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure.