Kilauea erupted in Hawaii today. There is aerial footage showing a line of lava in the middle of an otherwise-healthy forest, boiling and launching lava-meteors. What’s going on? Is this a fissure in the earth that is producing lava, or is it a flow that arrived from somewhere else that’s just incinerating biomass and thereby generating the gas to make it seem like it’s erupting from the earth right there?
Same with ground footage showing what appears to be an active eruption from the middle of a road. New lava reaching the surface for the first time, or flow from somewhere else that’s still outgassing?
Both of the things I mentioned can be seen in this video - the first one at 0:46, and the second at 0:35.
According to this article. There are now six separate fissures spewing lava in the residential neighborhood of Leilani Estates. The ground is just cracking open and opening multiple vents where lava is flowing.
A similar episode in 1955 had 24 vents and covered much of the town of Kalapana, west of the current eruptions. Satellite views show the lava field quite clearly.
The 6 fissures are occuring along a fault in the mountain.
Basically, the side of the mountain is sliding into the ocean.
The volcano keeps adding more and more mass on top, but doesn’t add anything into the ocean depths at the foot. So its like a side of a mountain that has been undercut by a river… but in this case, the lower part was never created… the top heavyness got their because the magma came up and set up there.
Another weakness is that the volcanic layers are all on a slope , and the volcanic rock is not particularly strong, there are even wet layers inside. So the side of this mountain is able to slide at a measurable rate. 80 mm annualy. See Koa'e Fault Zone - Wikipedia
Now whats happenned is that initial eruption has set this slow motion landslide off and turned it into an earthquake and the fissure has opened up. So the lava tubes that would otherwise have carried lava from the mountain are now broken and spewing stuff out. The rift creates a crack that is 1 or 2 or 15 metres wide… and this is a new lava tube. The lava then finds its way to the surface , as it has at 6 places along that rift.
Other fissures may be weaknesses in pre-existing lava tubes. One resident near Lailani said that he decided to leave because he could feel the rumble of something moving underground… the lava flowing down a lava tube. If it blocks at its current ends, it can melt its way out anywhere. An earthquake can open the tubes in the national park area, or block them…so lava tubes are dangerous things. they grow lava fields randomly… The entire area there ? its a large lava field… the surface is all lava flow …(and layers indicate massive explosion type events occurred in the past.)