sedatk
13 hours ago
I was there today. We happened to notice the smoke over Kilauea while driving to Hilo, then checked out USGS cams, and immediately drove there and spent the next 7 hours getting mesmerized.
As my first eruption encounter, I didn’t expect to experience several things like the heat even from a long distance, enough to keep me warm in my shorts at 60F, and the loud rumble, like a giant waterfall. The flow of lava was way faster than I expected too, almost like oil.
Mind blown.
kzrdude
12 hours ago
Hawaii volcanism is what geologists seem to call "nice and friendly" - low viscosity lava, not prone to explosive eruptions (unlike the stratovolcanoes of the Andes or the Pacific rim in general) - this is because it's caused by hotspot volcanism in Hawaii.
lazide
7 hours ago
It’s not nice and friendly because of the hotspot volcanism.
It’s because the hotspot has a chemical composition that is generally low in dissolved gasses and very liquid/flows well. (Lots of silicates I think?)
It tends to come out nicely and stay liquid as it leaves, so vents don’t plug up. Also, because of the relatively low dissolved gasses, pressure doesn’t spike as high when it’s flowing out of the chamber like many other magmas do, causing explosions.
Hawaii exists basically because it’s great for building up islands/mountains without blowing them up as part of the process.
CGMthrowaway
7 hours ago
Low viscosity is due to the LOW silica content. Tectonic setting is the primary factor determining the magma's final composition (basaltic) and therefore its physical properties (low silica, low viscosity). The gentle nature of Hawaiian volcanism is a direct result of its basaltic magma, which it has because the hotspot is located under thin, basaltic oceanic crust
kzrdude
7 hours ago
I don't think hotspots can be said to have different composition. But if the hotspot is under a continent or an ocean plate makes a difference for the type of eruptions. Hawaii is in the middle of an ocean plate, no continental crust there. So we get a basaltic eruption (comparatively lower silica content, low viscosity lava).
s1artibartfast
3 hours ago
Yellowstone is also caused by hotspot volcanism. The friendly eruption is a property of location, not hotspot origin.
Your initial post read the other way, which the parent post is addressing.
mdani
6 hours ago
Same here. I'd add that viewing the lava fountain at night was a mesmerizing experience. You get to see the full extent of red, glowing lava lake and the fountain. There were thousands of people and yet they appeared so small in front of the volcano. We did experience some ash and Pele's hair on the way to the park, near the black sand beach. I do recommend carrying a torch though at night, since it is pitch black at night. The lava illuminated the park with the red glow, but there were some parts where you do need a torch esp. if you park far away and walk.
JumpCrisscross
5 hours ago
> viewing the lava fountain at night was a mesmerizing experience
Is there anything comparable to the overview effect [1] that attends seeing a lava fountain in person?
supernova87a
4 hours ago
I am severely tempted to hop on a flight to go and see it, but wondering if it's such a "once in a lifetime" thing to go see? That, and if it'll peter out by the time I get there, and $500+ to just fly on a whim and stay overnight.
retSava
7 hours ago
I was at the Fagradalsfjall eruption at 2023. Had been to Iceland for two weeks w wife and daughter, and on the last day (since the signs were there) I decided to postpone travel home for two days (w + child wanted to go home). On my last day, the hike opened up and I went at approx 2100 hours to the volcano. That was an approx 10 km hike one way.
Amazing experience. A bunch of us were stupid as can be, but got as close as approx 50 m. Sounds really dangerous, but the sputter were not that violent yet, and the ground sloped away from us. Still, really stupidly dangerous (the sputter wall could've broken down, wind direction change, etc). But it didn't. Lots of moss fires, and walked into a small slope and immediately felt a sting in my nose and lungs from trapped gases so took that as a nope and went back.
Started walking back at 0130 something, boarded flight at 0600, fainted (I had done Mt Esja in the morning too). Sorry other passengers, it was inconsiderate of me and I was an asshole for that. But... that experience...!
mertd
5 hours ago
I was reading about shield volcanoes and it sounds like the low viscosity lava is the defining feature. So the flow is par for the course.