If you wanted to, and you had the right materials, you could probably sail on lava. (Side note: do not do this.)
For those craving a safer sailing/lava mashup, though, you can always look to Kilauea’s hyperactive Fissure 8, whose profuse effusion of lava is producing “lava boats” – several of which, as spotted by Hawaii News Now’s Mileka Lincoln, are pretty damn huge, about the size of several cars smushed together.
The video has to be seen to be believed, but suffice to say that it’s mesmerizing watching the massive buoyant chunk of recently cooled lava slowly and rather casually make its way downstream. In fact, this footage is a good reminder that, in some ways, lava flows have a lot in common with conventional rivers.
Over the past few weeks, the majority of the effusive, lava-generating activity in Kilauea’s Lower East Rift Zone (LERZ) has been focused on Fissure 8, while the others have become inactive – with the exception of a bit of sporadic lava spatter at a handful of others. Dr Wendy Stovall, a senior volcanologist with the United States Geological Survey (USGS), told IFLScience recently that this fissure focusing is exactly what you’d expect to happen for this type of eruption.
The flux of fluid lava emerging from Fissure 8 has created a distinct lava channel, a stream of molten rock contained within stationary lava blocks or levees, comparable to those you’d find in a real river. Somewhat similar to how you’d get chunks of ice floating downstream on particularly frigid rivers, you’re also getting lava boats – partially solidified masses of volcanic rock – drifting downstream toward the coast in this lava channel.
These boats emerge from two places: the increasingly tall cinder cone that’s building up around Fissure 8 as it continues to produce lava fountains and spatter, or the levees themselves. The USGS has noted that the term "lava boats" is a colloquialism, and that “accretionary lava balls” is more often used – even if lava boats sounds better when you’re talking about them flowing through a channel.
Much like their name suggests, these balls form as a core of already-solid lava rolls around and picks up fresh lava, which warps and cools around it. Here’s a photograph of one from a different volcanic event on Hawaii, taken in 1983 (spotted by LiveScience).
Just like the recent blue fire, volcano tornadoes, and volcanic haze (laze), accretionary lava balls aren’t a new phenomenon. Thanks to the fact that this eruption is probably the most documented natural disaster in human history, the public is getting to see things that previously would have been for scientists’ eyes only – from these lava boats on the flanks to the crater that’s swallowing up land at the summit.