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Scientists study volcanic lightning


Opening we're just a couple days away from the fortieth anniversary of mount St Helens nineteen eighty eruption N. as como as Ryan Harris tells us all these years later the mountain is still teaching us lessons there's a lot of learning at mount Saint Helens says Dr Seth Moran the scientist in charge of the U. S. geological survey's cascades volcano observatory who tells me there's still a lot being gleaned from the main event and the eruptions that happened in the weeks and months after to understand the Russian dynamics how the cloud evolved questions right now people are getting into about the generation of volcanic lightning and there was no lighting that was observed and reported and we can see some deposits in a pretty good idea of the timing of some of those deposits relative to say when volcanic lightning was was being generated this other some interesting ideas that are starting to be developed about when volcanic lightning occurs an interruption sequence and what it means when it starts happening in terms of I'm gonna bash in the air how far to go in and things like that Moran says the big lesson though is still the lateral blast in landslide caused by the eruption which broke trees like they were matchsticks or burned everything in its path because of the hot gases that escaped not to mention burying much of the area in deep debris and sending a mud flow down the North Fork of the total river the landslide was what took the pressure off of the magma that intruded into the volcano and I generate the lateral blast and it was certainly appreciated that the bulging of the north flank that was moving out at a rate of five or six feet a day that that was producing a flank that was unstable and it was certainly understood that rockfalls landslides avalanches were in the future if nothing happens but it wasn't appreciated how big that website it wasn't how discontinuous it was gonna it was gonna be Amaran says since then geologists have learned a lot about what deposits from that kind of a landslide looks like around volcanic areas and I've taken that lesson and applied it to volcanoes around the world and it's now much more appreciated by the volcano community that landslides are part of what volcanoes can do and that that is something that in certain situations where you've gotten unstable flank that's obviously building outwards that that's a very real thing that needs to be taken into account when doing hazardous substance those hazard assessments are important because doctor Moran reminds me of something we should all keep in mind not only is mount St Helens still active but source several other cascade volcanoes including mount

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