@Bastethotep #153021
Yeah, I was doing this off the top of my head. I for some reason thought it was Pliny the Elder. I did remember him being involved in the story somehow! Lol.
Re: pyroclastic flows. You’re right that they don’t contain magma. They do, however, contain lava blocks. They may be blasted out for very long as they do get blocked up but they are there. And yes, I’m aware they happen very fast. In the last words of David Johnston, you can hear his radio transmission “Vancouver, Vancouver this is it!” as the eruption just began and then he is gone. He was 5 miles away and was killed in an instant.
Basaltic flows: I don’t think I said anything about how long they go on. But yes they can cause damage far away, I said they are “mainly” localized, meaning that’s what happens most commonly but not always. And yeah I know they can kill lots of people with toxic gases, etc, and they can do it far away, I was just trying to give the most simple explanation without writing a thousand page post lol.
Hotspots: You are right that not all volcanoes are related to tectonics. The Ring of Fire (🎶I fell in to…🎶) around the Pacific is there because of tectonics. Basically the crust is being subducted around it. Hawaii is much closer to the middle and isn’t a part of that subduction zone. Yellowstone is also a hotspot, and it is also not particularly related to tectonics. And its composition is actually both rhyolitic and basaltic. Once again I was just trying to simplify things, and not write a thousand pager. But I should have brought it up. And yes, you are right about the mass extinction events.
And you are right about the “sea of molten rock beneath the earth’s crust” being wrong. Molten rock doesn’t work like water, although the basaltic compositions flow more freely than the andesitic or rhyolitic. It is still comparatively very viscous though. The only places it may be considered “flowing” are hotspots. I should’ve mentioned all that but by that time I was tired got distracted by a very cute rat. Also I think dude here thinks everything that led volcanism happened a long time ago, when in reality it is a constant process. The Pacific is currently being subducted. Hotspots like Hawaii are still taking part in creating new ocean crust. Mt. Mazama, which exploded and created Crater Lake in Oregon, is currently creating a new dome for itself. So is Mt. St. Helens. In 10 million years (a blip on the geologic scale) the continents could look significantly different and the oceans much differently distributed.
I love the discussions we have here!