Images

Detail of levee on an active channelized aa flow. Note the pahoehoe overflows in the levees and the level of the active flow below the tops of the levees. This lower flow level is not allowed in the commonly used "Bingham" model of lava flows.

A section of burst tumulus that has fallen away from the larger structure. 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.

An a'a' channel near the Royal Gardens subdivision on Kilauea Volcano, Hawaii. The flows in the background are from the 1980s. Note that the flow level is below the levees and the pahoehoe overflows emplaced on top of the a'a'. 

Image of Sojourner, paving the way for future, more sophisticated, rovers to study Mars and other planetary bodies. 

Pu’u ‘Ō’ō is a cinder and spatter cone in Kilauea’s east rift zone. It began erupting on January 3, 1983; a summary of its eruption can be found here. This image shows the result of the largest of the collapse pits that began to appear around 1993.

This image shows two views of the trailing hemisphere of Jupiter's ice-covered satellite, Europa. The left image shows the approximate natural color appearance of Europa. The image on the right is a false-color composite version combining violet, green and infrared images to enhance color differences in the predominantly water-ice crust of Europa.

Natural color view of Ganymede from the Galileo spacecraft during its first encounter with the satellite. North is to the top of the picture and the sun illuminates the surface from the right. The dark areas are the older, more heavily cratered regions and the light areas are younger, tectonically deformed regions.

A crystallized dacite flow in northern Chile. Dacite is extrusive and the volcanic equivalent of granodiorite. 

Channelized flows on Socompa. Socompa is a large stratovolcano on the border between Chile and Argentina, the youngest of a chain of volcanoes that runs northeast to southwest.

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.

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.

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.

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.

The original Magellan Compressed Mosaicked Image Data Record (C3-MIDR) archive contains three times compressed mosaics of image swaths (C-BIDRs) at a resolution of 2025 m/pixel. C3-MIDRs consist of mosaics generated by computing 3x3 pixel arithmetic moving averages from the C2-MIDRs.

Pu’u ‘Ō’ō is a cinder and spatter cone in Kilauea’s east rift zone. It began erupting on January 3, 1983; a summary of its eruption can be found here. This image shows the cone just starting to form a collapse pit on its flank.