Questions tagged [pyroclastic-flows]
concerning the formation, behaviour and composition of this form of eruption (hot currents of gas and rock moving along or close to the Earth's surface)
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In which conditions ignimbrites devitrifies?
Devitrification is the crystallization of volcanic glass to crystals. Obsidian groundmass -black in color- turns to white with devitrification.
I want to learn why devitrification takes place.
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Can people on the side of a volcano survive the eruption?
Imagine a couple of people are at the side of a huge volcano, halfway to the summit, when it erupts. There's an opening to the Chambers right beside them.
Fire belched from its riven summit. The ...
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Interpreting an outcrop of a thick pure silica bed in a volcanic setting
How can a nearly pure silica bed with 250 m x 50 m x 1.5 m dimensions be interpreted in a volcanic/pyroclastic setting? Here is a photo of it.
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Pyroclastic density currents interpretation
How to interpret bubble voids in pyroclastic density currents? You may see the case on the photo attached. It is; Miocene, densely welded, crystal bearing, LT. Do they have to occur on the top of the ...
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Why are pyroclastic flows ground-bound?
This bugged me for a while:
Pyroclastic flows are fast (up to 700 km/h (430 mph) according to Wikipedia) and typically roll down the slopes of a volcano. E.g. here https://www.youtube.com/watch?v=...
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Are Pompeii and Herculaneum unique?
Has anyone ever found or gone looking for similar locations, i.e. volcanic eruption sites in which unfortunate victims – human and non-human – have been entombed in the volcanic ash, with the ...
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What is the mechanism for deep-sea volcanism of the Gakkel Ridge in the Arctic?
Related to an earlier question, What is the geochemical source for the helium detected in deep Arctic explosive eruptions?, where it is stated in the linked article that there is evidence of explosive ...
user889
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Can pyroclastic flows cross water?
While reading the Wikipedia article on pyroclastic flows, I noticed that there's a section called 'Interaction with water'. This piqued my interest, as I was under the impression that lava generally ...
user13