Check out this monster 'boat' floating in lava rapids

PUNA, HAWAII (HawaiiNewsNow) - We've seen lava rapids. Lava "bergs." And now — a lava "boat."

Puna resident and community activist Ikaika Marzo captured incredible video of the massive rock floating in the channelized lava flow from fissure no. 8.

He said the "boat" is actually a sizable chunk of land — about 20 feet by 20 feet.

The term used in volcanology is actually "lava ball" or "accretionary lava ball," according to U.S. Geological Survey scientist Wendy Stovall.

The balls form when portions of cinder cones or channel levees break apart and are then rafted within a lava channel.

"They can roll around as they move through the channel and liquid lava will coat itself to the outside making the lava ball grow as it moves along," Stovall said.

"Smaller chunks of levee or cooler lava can also tack itself on, and the whole thing continues to grow. Imagine making a snowball by rolling it in snow. It's a similar, albeit much hotter, process."

The "balls" can be many yards across. In Marzo's video, the "lava boat" slowly makes its way into the frame before getting picked up in lava rapids and then breaking apart.

"This is one of the biggest lava boats I have seen," said Marzo. "Just amazing."

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