2) Airborne Lava Fragments
Most volcanic eruptions produce fragments of lava that are airborne
for at least a short time before being deposited on the ground. These
fragments are called "tephra" and include ash, cinders,
and Pele's hair. In Hawai'i, tephra is usually ejected by lava fountains
and poses a
serious hazard only in the immediate vicinity of an eruptive vent.
Windborne tephra, however,
can be disruptive at greater distances. The combination of high lava
fountains and strong winds may result in tephra being carried many
miles downwind of the eruption site. During lava fountaining episodes
at Pu'u 'O'o from 1984 to 1986, the prevailing trade winds deposited
most of the tephra in remote areas of Hawai'i Volcanoes National Park,
but small particles reached the town of Naalehu 39 miles away. During
the same episodes, Southwest 'Kona'
winds occasionally carried tephra to Hilo, 22 miles from the vent.

A close-up view of tephra, including cinders and Pele's hair.
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