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Explosive Eruptions at Kilauea Volcano?
Explosive eruption column rises from Halema`uma`u Crater Kilauea Volcano, Hawai`i
Kilauea is justly renowned for its lava flows and fountains. Residents
and visitors alike enjoy the beauty and the relatively benign nature of
the activity. Few realize, however, that Kilauea has a dark side-explosions.
The first western visitor to Kilauea, Rev. William Ellis on August 1, 1823,
was told by residents that, "for many kings' reigns past [Kilauea had been]
throwing up, with violent explosion, huge rocks or red-hot stones." These
same residents related the oral tradition of a battle between the volcano
goddess, Pele, and her erstwhile lover, the pig god Kamapua`a, that ended
with Pele "driving Kamapua`a into the sea, whither she followed him with
thunder, lightning, and showers of large stones."
Twentieth-century geologists have confirmed this oral history and legend.
Surface deposits around Kilauea's caldera tell of a series of explosions
lasting from about AD 1500 to AD 1790, when members of a warring band were
killed in the last major explosion of the series. Evidence has recently been
discovered of explosions about 1,000-1,200 years ago. And, explosive activity
from an old caldera at Kilauea is known from about 2,100 and 2,800 years
ago. Still farther back in time, huge explosions deposited ash across the
southwest flank of Kilauea, 20 km and farther from the vent.
In fact, Kilauea erupts explosively about as often as does Mount St. Helens.
In this respect, Kilauea can be called an explosive volcano. Of course, most
of its eruptions produce lava flows and fountains, so the explosive nature
of the volcano tends to be overlooked. Steam derived by heating of groundwater
is interpreted as the driver for the explosions at Kilauea, and probably
collapse of a caldera or pit crater to below the water table is necessary
to generate large explosions.
A new fact sheet has been published describing some aspects of the explosive
history and the suggested mechanism for the generation of the explosions.
The single page fact sheet, Explosive Eruption
at Kilauea Volcano, Hawai`i? can be viewed online as a PDF publication.
The most current
Volcano Watch article.
The Probability of Lava Inundation at the Proposed and Existing Kulani Prison
Sites, 1998, USGS
Open File 98-794.
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