In visible light (top image), fresh lava flows are difficult to distinguish from the black rock of Tolbachinsky Dol, a volcanic plateau on Russia’s Kamchatka Peninsula. The high altitude and northern latitude of the plateau (as far north as Moscow) preserve the barren landscape left behind by past eruptions. In contrast, the fresh lava stands out clearly against the vivid green of low-elevation meadows and forest.
On the plateau itself, the only color is near the summits of scattered cinder cones. The cones form around volcanic vents and are exposed to escaping volcanic gases in the course of an eruption. The gases react with the iron-rich lava cinders, essentially rusting the rocks. Sunset Crater in Arizona is named for the colorful end result of this process.
Shortwave infrared and near-infrared light (combined with green light in the lower, false-color image) highlight another aspect of Tolbachinsky Dol—the ongoing eruption of Tolbachik Volcano. Hot surfaces glow in shortwave infrared wavelengths. The active vent and lava flow are bright red, along with scattered lava “breakouts”at the front of the flow. High temperature surfaces in the scene also glow in near infrared light, revealing a lava pond in the active vent and fluid lava in the center of the lava flow.
These images were collected by the Advanced Land Imager (ALI) on the Earth Observing-1 (EO-1) satellite on June 6, 2013.
NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.