1980 eruption of Mount St. Helens

Automatic TRANSCRIPT

So my episode today. is about the nineteen eighty Mount Saint Helens eruption. So now, we weren't alive then even though we were not alive, then it was you know years until Jillian. Many years. Until we were born. We are in our. Mid Twenty. S. So we're very youthful. Yeah. We say what's a CD or whatever I don't know anything I couldn't even pretend to be a teenager because I have no idea went technology. Don T TIKTOK ON THE TIKTOK You know on the TIKTOK so. Nineteen Eighty Mount Saint Helens eruption has a lot of parallels to what's going on in the world today, but it's an interesting story. So to to start with for our non US friends and Non West Coast friends, I didn't know the details about this when I started researching it but Mount Saint Helen's which is known as a lot lot to the indigenous lets people and Lou wit. Luella cloud to the click a tat is an active stretch of Okano located in. Skamania. County. Washington in the Pacific Northwest region of the United States I. Apologize to the Washingtonians. If I pronounced Skamania county your Skamania county incorrectly. I'm sure I will get an email about this. Fifty miles eighty kilometers northeast of Portland Oregon Ninety, six miles or one hundred and fifty four kilometers south of Seattle Washington. So to get a sense of where Mount Saint Helen's is. If you're thinking of both Washington state and Oregon is roughly like. Square ish rectangular ish in shape with Washington, in the north and Oregon just below. Mount Saint Helen's is in the lower left quadrant of Washington state near the border of Oregon. and. She's roughly halfway between Portland, and the Portland Oregon and Olympia Washington, which is the Washington state capital. Okay. also relevant northeast of Mount. Saint Helen's is what's called Spirit Lake. And there's a bunch of little rivers and creeks in that area just due to like the geology of the area but almost directly north of the mountain is the north fork toodle river. River toodle or Poudel T. O. U. T.. L. E. Title River. So. Also? Mount Saint. Helen's takes its English name from the British diplomats. Lowered Saint Helen's is a friend of explorer George Vancouver who made a survey of the area in the late eighteenth century The volcano is located in the cascade range is part of the cascade volcanic arc, which is a segment of the Pacific Ring of fire that includes over one hundred and sixty active volcanoes and for the record before the explosion mount. Saint, Helen's stood at nine, thousand, six, hundred and eighty feet high. So. They knew it was part of the ring of the ring of Fire Okay Yeah Yeah So. They knew as part of the ring of fire. It had experienced some activity throughout recorded history but it. It remained dormant basically from its last period of activity in the eighteen, Forty S and eighteen fifties. So by one thousand, nine hundred had been more than one hundred years before there was any like really significant activity that includes ash like little burps and like any kind of flow or anything like that. So. At this point people were pretty complacent thinking nothing's going to happen anytime soon it's fine like it's a dormant volcano for all intents and purposes until we get to the spring of nineteen eighty. Okay. So, there were several small earthquakes beginning on March fifteenth of that year indicating that magma may have begun moving below the volcano also just as an f. y. we talked about natural disasters on episode sixty one which was called here I am rock. You like a hurricane I talked a little bit about that about volcanoes in that episode. So if you want to refresh your memory about the basics of what's in a volcano check that out episode sixty one, it's very good. Thank you. So on March Twentieth Three Forty Five PM Pacific Standard Time, which everything will be NPS T. Shallow magnitude four point two earthquake centered below the volcano's north flank signal the volcanoes return from one hundred, twenty three years of hibernation. A gradually building earthquake swarm saturated area seismographs, and started to climax at about noon on March twenty fifth reaching peak levels in the next two days including an earthquake registering five point one on the Richter scale. A total of one hundred and seventy four shocks of magnitude. Two point six greater were recorded during those two days. That's a lot. Yeah. So geologists in that area are like look is no not a great sign. Initially. There was no direct sign of eruption but small earthquake induced avalanches of snow and ice were reported from aerial observations. So this mountain is shaking and you know stuff is falling off. It's not it's not nothing. At twelve thirty, six PM on March twenty seventh phreatic eruptions which are explosions of steam caused by magma suddenly heating groundwater. So that's like a quick like spur. Of, like Ash and Steam K ejected and smashed rock from within the old summit crater. Excavating a new crater, two, hundred and fifty feet wide. And sending an ass column about seven thousand feet into the air. So you yeah, knock. Great. So by this date along, east trending fracture system had also developed across the summit area. So there's cracks forming in the summit. This was followed by more earthquake swarms in a series of explosions that said ash even higher above there. And most of this ash fell between three and twelve miles from its fendt. But some was carried hundred fifty miles south to bend Oregon or two hundred and eighty five miles east to spokane Washington. So the ash went pretty far and those who were like what the What is happening here? So? then. A second new crater and a blue flame were observed on March twenty ninth.

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