Kilauea Volcano’s
current eruption began in 1983, covering more than 120 square kilometers (48
square miles) of the island of Hawai’i in fresh lava. This false-color
satellite image (top) shows how lava tubes carry fluid basalt more than 10
kilometers (6 miles) from Pu’u ’O’o, the center of the eruption.
Instead
of the red, green, and blue light in a conventional photograph, the false-color
image at the top of the page contains information in two invisible wavelengths
(shortwave infrared and near infrared), and one visible wavelength (green). Old
lava flows absorb light in all three wavelengths, so they appear dark. Molten
lava—and, to a lesser extent, freshly solidified lava—“glows” in shortwave
infrared light, but absorbs near infrared and green light, so it appears red.
Vegetation is bright green, clouds are white or cyan, and the ocean is dark
blue. The image was acquired by the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite on October 13, 2012.
The
1983 eruption started at Pu’u ’O’o crater, which is the current site of
upwelling lava. Despite being partially covered by clouds, Pu’u ’O’o is bright
red in this image due to heat from the lava lake within. Lava flows from the
crater towards the coast, hidden from view by insulated lava tubes. Some lava re-emerges from the tubes at
the top of the pali—the steep slope that separates Kilauea’s eastern rift from
the coastal plain.
The
remainder of the lava continues through the tube network to the bottom of the
pali, where it pools and eventually surfaces in broad lobes. According to the
U.S. Geological Survey’s Hawai’ian
Volcano Observatory, the
lava is currently creeping across the coastal plain towards the ocean.
A
photograph taken on October 4 (lower image) during a flight by USGS scientists
shows the lava just as it reached the bottom of the pali. Most of the lava
surface is dark in daylight. Only the hottest, most fluid lava glows orange or
yellow. Gray volcanic plumes blowing from right to left trace the path of the
lava flow down the pali.
1. References
2.
USGS Hawaiian
Volcano Observatory. (2011) Pu’u ’Ō’ō-Kupaianaha Kīlauea’s East Rift Zone Eruption 1983 to present.Accessed
October 19, 2012.
3.
USGS Hawaiian
Volcano Observatory. (2012, October 19) Kilauea Status Report. Accessed October 19, 2012.
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Related Reading
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Hawai’ian Volcan
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