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Showing posts with the label basalt

Never stick your hand into a viscous material

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- Dr. Alison Graettinger “If there is one thing I’ve learned, it’s never to stick your hand into a viscous material” I came across that quote again in the signature of a colleague's email. It is from the 2004 Van Helsing movie. The movie is a bit cheesey, but that advice is very sound. So what does viscous mean? The term viscosity is not a word that most people use every day, but a really useful one if you want to know anything about a fluid or anything that flows. It gets used by your mechanic when discussing different types of oils to put in a car’s engine. Or occasionally in movies involving evil scientists, monsters and gooey things (see above). Even TSA has to have a basic understanding of viscous things as they limit all things that pour, spreads or smears. This covers a range of things that, while they behave like fluids (which means they deform under a force), you might not immediately think of them. Unfortunately, TSA is as just as likely to take away your hair gel...

Spectacular volcano videos: Identifying eruption processes

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- Dr. Janine Krippner We are fortunate that there is a large availability of volcanic eruption videos online for all of us to enjoy (see below warning), and we can learn a lot from them too. When I am looking at my satellite images of dome collapse block and ash flow and column collapse pyroclastic flow deposits on Shiveluch and Mount St. Helens volcanoes I have videos of these processes running through my mind. This is a short guide to what you are seeing in these incredible videos. WARNING: There are very dangerous and life threatening hazards associated with retrieving this footage, and here at In the Company of Volcanoes we strongly discourage anyone from trying to take your own. It is never, ever worth risking your life. --- This video shows the dome at Unzen volcano undergoing a partial collapse in 1991. This shows how a near-solid body of rock rapidly fragments down to smaller pieces of rock and ash, creating a billowing ash plume rising from the block and ash...

The eruption is how big? Deposit volume story

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-Alison It seems obvious to say volcanoes are big, but as with anything in geology size is not immediately obvious. Volcanoes can loom over a landscape, spread ash over large chunks of the planet and even influence our climate- that all sounds big. On the scale of an individual human any eruption is big. They are frequently faster than, slower than (yes both), hotter than and physically larger than a human being. One of the exercises I use when teaching volcanology is focused on understanding just how big, "big" is. We go about this by finding things that we already understand the size and compare them to volcanoes. Like many natural processes (and humans), volcanoes and volcanic eruptions come in all shapes and sizes. If volcanoes only had one size and style of eruption our job studying them and anticipating future eruptions would be much easier. The only human-sized volcano I have ever seen. It was a volcano costume in Kagoshima Japan in 2013. We need to be able...