Tough Kittehs and Cowardly Goggies

Our own Heliconia sent us this bit o’ hilarity. I about died laughing.

Misha only wishes she could do this to dogs. But Misty, the ginormous husky we lived with for a time, had too thick an undercoat to be impressed by a snarling, spitting cat with no front claws. Despite the teeth.

Bonus: cats and water, always good for a larf. (Warning for the tender-hearted: there are kitties getting a fishy at the end.)

Our big mama cat once made the mistake of thinking the tub was empty of everything except my mom. She loved to play in the tub. So just imagine this enormous calico cat, mean as sin and not shy about demonstrating displeasure, sauntering into a bathroom as a lady shaves her legs and her daughter babbles at her from a perch atop the toilet seat. Imagine both of us watching the cat, thinking nothing much of it until the kitty stops, gathers her hindquarters, flicks her tail, and begins her jump. Imagine both of us shouting at the kitty that there’s water in there as she sails through the air and sploosh. Imagine the chaos as the cat frantically splashes, my mother drops her razor and tries to get a grip on the cat without getting shredded, and water goes absolutely everywhere. I’ll never forget the image of that struggling, sopping, howling bundle of misery being lifted dripping, drooping and writhing with my mom holding her just under the forelegs with arms extended. Poor kitty and mommy. At least they both survived, although neither with dignity intact…. Still, you gotta hand it to my mother’s reflexes: she survived without bone-deep wounds. Good reaction time, that woman.

Needle Ice Mania: Nature Is Art (Even When Attempting to Freeze You to Death)

Ah, winter. Ah, week-of-sub-zero-temperatures. You know, we’re used to chill in Seattle, but we’re not used to day after day after day after etc. of freezing cold. The moderating influence of the nearby ocean generally keeps us from being uber-icy. But then comes a cold snap, and it seems like the whole place freezes solid.

But the neat thing is, in places, our wet ground stays sorta warm, while the air is sub-freezing. And magic happens. Needle ice!

Needle ice at me apartment complex.

Needle ice at me apartment complex.

There it was, rearing out of the ground, tall and bold after having grown for several days. This is up against one of the buildings, at the edge of the lawn, under the rhodies, where the ground has a chance to stay warm and this stuff’s reasonably protected.

Needle ice, showing the tiers marked off by the grains of soil it incorporates as it grows.

Needle ice, showing the tiers marked off by the grains of soil it incorporates as it grows.

I’ve put these on Flickr, so you can click through for the maclargehuge images. It’s worth it. This stuff’s pretty amazing.

Needle ice that's formed little spikes, with another tier growing on the spike. Wowsa.

Needle ice that’s formed little spikes, with another tier growing on the spike. Wowsa.

Moar spikes n' tiers.

Moar spikes n’ tiers.

Here ’tis with my lip balm for scale.

Needle ice with lip balm tube for scale. This stuff's at least four inches tall.

Needle ice with lip balm tube for scale. This stuff’s at least four inches tall.

This year, I knew to keep an eye out for it. I found a tiny bit up near work, when I was taking a walk with B, and he was delighted by the stuff. It’s easy to miss unless it’s done what this stuff’s done and emerges completely. It starts out sorta underground, and you have to look for the odd patterns the soil makes when needle ice is pushing it up. You look for it where the ground has a chance to stay warmer than the air, and in shaded places where the sun hasn’t mucked up the ice-creation process. The strip of lawn right behind our Staples is a great place to look. You can see it pushing the moss up. And if you’ve gone shopping, you might even have something for scale.

Needle ice under moss. Cake notepad for scale.

Needle ice under moss. Cake notes for scale.

There, and you’ve got a look at Starspider’s Christmas gift, too – a notepad made to look like a wedge o’ cake, complete with pen-candle. Cute, eh? It’s sitting in a little depression made by my foot. Needle ice isn’t exactly strong.

I got some good shots looking down into the ice.

Looking down into needle ice.

Looking down into needle ice.

Kinda wild, eh? But not as fantastic as this one.

Needle ice, shot with the camera stuffed in to the crevice. Look at that hoarfrost on it!

Needle ice, shot with the camera stuffed in to the crevice. Look at that hoarfrost on it!

It’s so cold the ice is growing ice – some of it has hoarfrost growing on its needles. And if we look closely at that image, we can see the super-sharp crystal perched like a pointed tower there.

Cropped portion of image showing detail of hoarfrost.

Cropped portion of image showing detail of hoarfrost.

Love this stuff.

This is another neat one: a sort of crevasse that wound and twisted and looked like a black river in the ice, flowing between ice-column cliffs topped with moss. Sorta geologic, that.

Crevasse.

Crevasse.

One could easily make fantasy worlds outta this stuff. It’s amazing.

Needle ice from above, with red berry trapped upon it.

Needle ice from above, with red berry trapped upon it.

You can see how it basically grabs and pushes up anything above it – here, the brown stuff is soil and sand. When it melts, it’ll leave that soil weirdly-patterned. See how strong it is – in this image, it’s lifted up pebbles that aren’t all that small.

 

Large pebbles embedded atop needle ice.

Large pebbles embedded atop needle ice.

It got positively artistic in places. Here’s a pebble enthroned by itself, surrounded by taller columns of needle ice that for some reason flopped as they grew, creating icefalls. Lovely!

Pebble surrounded by needle icefalls.

Pebble surrounded by needle icefalls.

Here’s another of the same, shot from pebble-level, with that big icefall beside it.

Icefalls and pebble closeup.

Icefalls and pebble closeup.

I took B to show him the needle ice by the house the next day, but alas, the kids had discovered it and stomped it flat. Sigh. Still, I got to photograph it when it was whole, and they left this chunk to show you. Look at the tiers! Look at the size of the thing!

 

Moi gloved hand holding a chunk o' needle ice. I count at least four tiers - and it's nearly as long as my fingers. Huge!

Moi gloved hand holding a chunk o’ needle ice. I count at least four tiers – and it’s nearly as long as my fingers. Huge!

Alas, the ice is short-lived. But while it’s here, it’s gorgeous, and I feel lucky to live on a world where such things happen, in a universe where nature grows wonders on a regular basis. And I’m really bloody lucky I had a warm bath to come back to when the jaunt was over!

 

The Cataclysm: “That Whole Mountain Range Had Just Exploded”

A few seconds after the beginning of the directed blast, life within roughly ten kilometers (6.2 miles) of Mount St. Helens within the blast zone was about to be extinguished.

Oblique aerial view of the laterally blasted material deposited in the North Fork Toutle River valley approximately seven miles away from Mount St. Helens. Note the dense ash in the air, the ash-covered blast deposits, and the brown mudflow deposits. Cowlitz County, Washington. May 19, 1980.

Oblique aerial view of the laterally blasted material deposited in the North Fork Toutle River valley approximately seven miles away from Mount St. Helens. Note the dense ash in the air, the ash-covered blast deposits, and the brown mudflow deposits. Cowlitz County, Washington. May 19, 1980. Image courtesy USGS.

“Directed blasts,” Rick Hoblitt, Dan Miller, and James Vallance wrote in their 1981 paper on the blast deposits, “typically devastate large areas… and kill essentially all above-ground life within these areas.” Human and animal, arthropod and avian, tree, bush and flower, all perished. Between its kinetic and heat energy, the directed blast released the equivalent of 24 megatons of energy in a few short moments. This is one megaton short of the theoretical yield of the largest hydrogen bombs the United States ever created; the first nuclear bombs to destroy a city were only 15 and 21 kilotons, respectively – orders of magnitude smaller. Instruments measuring the blast saw “amplitude variations comparable to those caused by detonation of nuclear devices in the 1-10 mt [megaton] range.”

There are words for eruptions like this. They belong to the Volcanic Explosivity Index. The qualitative description for Mount St. Helens’s climactic eruption is “paroxysmal,” but it achieved a mere “very large” as a descriptor. Some versions of the VEI become speechless at that point; others scale up to “huge,” “humongous” and “indescribable.” Mount St. Helens was just above average.

In the figure, the volumes of several past explosive eruptions and the corresponding VEI are shown. Numbers in parentheses represent total volume of erupted pyroclastic material (tephra, volcanic ash, and pyroclastic flows) for selected eruptions; the volumes are for uncompacted deposits. Each step increase represents a ten fold increase in the volume of erupted pyroclastic material.

In the figure, the volumes of several past explosive eruptions and the corresponding VEI are shown. Numbers in parentheses represent total volume of erupted pyroclastic material (tephra, volcanic ash, and pyroclastic flows) for selected eruptions; the volumes are for uncompacted deposits. Each step increase represents a ten fold increase in the volume of erupted pyroclastic material. Image and caption courtesy USGS.

What made her so wildly destructive was the direction that energy was released in. She didn’t just explode up into empty air; when her north face collapsed, it allowed the confined energy of the cryptodome to escape sideways, channeling that release along the ground, where the people and plants and animals were.

The initial blast accelerated from around 50-100 meters per second (112-224mph) at Sugar Bowl dome to at least 156 m/s (349mph) by the time it destroyed seismic station SOS four kilometers (2.5 miles) away. Leaving the high pressure of the vent and encountering the relatively low pressure of the open air, it spread out, covering more than 180°, bearing down on people to the west and east in the South and North Fork Toutle River drainages.

MSH Eyewitnesses

Map showing the area devastated in the directed blast, and locations of witnesses interviewed by USGS geologists. Modified after Figure 35, Rosenbaum and Waitt 1981, in USGS Professional Paper 1250. Image courtesy USGS.

Canadian geology student Catherine Hickson and her husband Paul watched the eruption unfold from fifteen kilometers (9.3 miles) east of the summit as their terrified dogs cowered beside them. At first, the cloud raced smoothly down the crumbled north face of the mountain; then it began billowing eastward, toward them, overtaking the avalanche. Watching it, realizing it would plow right through the river valley between them and the mountain, Catherine thought of two words: “nuée ardente,” glowing cloud. An eruption cloud like this had raced down from Mount Pelée and reduced the thriving seaport of Martinique to ruins, killing nearly thirty thousand; one had descended upon Pompeii from Mount Vesuvius and left no survivors. She knew a car stood no chance. “So we fled,” she said simply in a letter she wrote to a friend after the eruption.

As her husband sped down a narrow logging road, dodging frantic elk and falling rocks, she snapped a few pictures of the cloud bearing down on them.

Nine kilometers (5.6 miles) west of the summit, Joe Sullivan, his wife, brother-in-law, and friend Mark Dahl fled west down the South Fork Toutle River as the enormous black eruption cloud plowed over the hills. They were speeding at 121-129 kilometers per hour (75-80 mph,) but after less than four minutes, the ash-laden cloud billowed over a ridge ahead of them to the northwest – it had outraced them down the North Fork Toutle River valley.

Behind them, only eight kilometers (5 miles) west of the exploding volcano, Dave Crockett found himself trapped.

All of them were in line of the blast.

In this schematic of the directed blast, the blast is just beginning to overtake the debris avalanche. It will rapidly accelerate to at least 562 kilometers per hour (349 mph) before slowing to a more sedate 100 kph (62 mph) 25km (15.5 miles) away. Some estimates place its top speed at 650 kph (404 mph). Image courtesy USGS.

In this schematic of the directed blast, the blast is just beginning to overtake the debris avalanche. It will rapidly accelerate to at least 562 kilometers per hour (349 mph) before slowing to a more sedate 100 kph (62 mph) 25km (15.5 miles) away. Some estimates place its top speed at 650 kph (404 mph). Image courtesy USGS.

The pyroclastic density current of the directed blast would later be described by Hoblitt, Miller and Vallance as “a subhorizontal fountaining mass of debris and expanding gasses.” Those gasses ripped and plucked existing rock from the debris avalanche and the ground, mixed that rock with the hot young dacite from the cryptodome, and hurled the whole mass along at incredible speeds. Where the cloud passed over the debris avalanche, it entrained more cool material, which reduced its temperature, but to the east and west, it had less loose rock to mix in and remained ferociously hot – up to 300°C (572°F). Witnesses on Mounts Rainier and Adams watched it flow through valleys and over ridges, hugging the ground, ignoring topography. Where it passed, nothing was left standing. Trees were ripped down, blown away, many of them within 12 kilometers (7.5 miles) of the volcano reduced to splinters and mixed with the debris. Cars, trucks, and logging equipment were sandblasted, battered, scorched: the velocity of the blast cloud combined with its pummeling rocks and logs sometimes punched vehicles hard enough to move or flip them within all but a third of the downed timber zone.

People, animals, and plants caught within this part of the devastated area did not survive. In less than four minutes, a brilliantly sunny morning had turned into a searing, dark, fatal blizzard of stone, and they were gone, most of them asphyxiated by incandescent ash and gasses.

Near view Columbian photographer Reid Blackburn's car, buried four feet deep by the deposits left by the directed blast and subsequent ashfall. He was at Coldwater I, 10.5 kilometers (6.5 miles) northwest of Mount St. Helens's summit. Image credit D. Dzurisin via USGS.

Near view Columbian photographer Reid Blackburn’s car, buried four feet deep by the deposits left by the directed blast and subsequent ashfall. He was at Coldwater I, 10.5 kilometers (6.5 miles) northwest of Mount St. Helens’s summit, and died in the blast. Image credit D. Dzurisin via USGS.

The atmosphere saved the Hicksons and others who had been in the path of the blast cloud to the east and west. As rarefaction (expansion) waves reflected off the atmosphere and became compression waves, the blast was deflected toward the north. It stopped just 3 kilometers (1.9 miles) short of the Hicksons; it missed Dave Crockett by perhaps half that distance. The vagaries of fluid dynamic had steered destruction away from those fortunate few.

But people to the northwest, north, and northeast were still in its path. Nineteen kilometers (11.8 miles) north, in the green river drainage, Al Brooks and his friends Dale and Leslie Davis snapped a photo as the blast cloud rose over a ridge north of Coldwater Creek. Seconds later, they would tell USGS geologists, “it looked like that whole mountain range had just exploded.” Other witnesses to the north saw the wall of ash and rock, now a few thousand feet high, suddenly rise in front of them. And that blast cloud, “a boiling mass of rock… just as high as you could see” was bearing directly on them.

powered by Splicd.com

 

Previous: The Cataclysm: “A Sudden Exposure of Volatile Material.”

Next: The Cataclysm: “A Boiling Mass of Rock.”

References:

Hickson, Catherine J. (2005): Mt. St. Helens: Surviving the Stone Wind. Vancouver, BC, Canada: Tricouni Press.

Lipman, Peter W., and Mullineaux, Donal R., Editors (1981): The 1980 Eruptions of Mount St. Helens, Washington. U.S. Geological Survey Professional Paper 1250.

 

Previously published at Scientific American/Rosetta Stones.

The Red Waterfall at the Scene of a Volcanic Disaster

I was going to save this photo for when I’d had time to go back through my recording of the ranger talk and recall what it was the ranger said about it – iron staining? Bacteria? They don’t know? But some of you wanted a larger image of Mount St. Helens’s lovely red waterfall, and so a larger image you shall have right now. Because I love you:

Image is a close view of the red-stained streak left by a waterfall that plunges down a bare ridge within the blast zone at Mount St. Helens.

Red Waterfall at Mount St. Helens

And because I love you very, very much, thee shall have an image of the red waterfall with Mount Adams peeking over it.

A photo from a different angle shows the red waterfall, with the snow-covered summit of Mount Adams behind it.

Mount Adams peeks over the ridge where the red waterfall is.

Eventually, I’ll have a whole big missive about that red waterfall prepared for you. Eventually.

The Cataclysm: “A Sudden Exposure of Volatile Material”

The cryptodome growing within Mount St. Helens sowed the seeds of its own destruction. Had it been a small thing, it might have become a younger sibling to Goat Rocks. Pacific Northwesterners might have seen a few displays of volcanic fireworks, another dome added to the edifice, and a return to serenity. It hardly would have made the news.

But this dome, unlike Goat Rocks, kept growing, there beneath the surface. It set groundwater steaming. The hydrothermal system driven by its heat caused some pretty spectacular phreatic eruptions. It severely over-steepened the volcano’s north flank.

The first in a series of time-lapse photos taken April 13th, 1980, showing the growing bulge as an eruption cloud grows behind it. Image courtesy G.A. Coyier, USGS.

The first in a series of time-lapse photos taken April 13th, 1980, showing the growing bulge as an eruption cloud grows behind it. Image courtesy G.A. Coyier, USGS.

And it kept growing, right up until the end, when an earthquake on the morning of May 18th, 1980, brought the whole thing down.

This is a story of seconds. A lot can happen in a few seconds. A whole mountain can change.

Before 8:32:11 am Pacific Daylight Time, the cryptodome had been following the usual trajectory of masses of magma hanging about under a volcano’s skin. The hot dacite was cooling down toward the point where liquids become solids. Various minerals were crystallizing as the magma cooled; toward the outside, where fresh dacite met old volcanic products and water circulated through the hydrothermal system, things had cooled a bit more than in the interior, and probably formed something of a dense crust with only minor, if any, vesicles. Other bits of the dome might have been a little more bubbly, with gasses forming more vesicles than at the relatively solid outer edges. But everything was under pressure – 175 bars of it – and so most gasses would have been dissolved within the melt. Even the water heated by the magma hadn’t boiled. Under that much pressure, it couldn’t get steamy.

A large block of mixed magmas ejected in the directed blast on May 18th. Geologist's foot for scale. Image courtesy Helena Mallonee.

A large block of mixed magmas ejected in the directed blast on May 18th. Geologist’s foot for scale. Image courtesy Helena Mallonee.

This all sounds very quiet and happy, but gasses, including water vapor, that are under pressure are being forcibly confined to a small volume. They’re the kind of things that normally take up quite a bit of space. Give them an opportunity, and they’ll proceed to do so rather emphatically.

Opportunity rang at 8:32:11 am PDT in the form of a magnitude 5.1 earthquake. It took about ten seconds for the unstable north face to begin sliding. Old rock, debris, domes, dirt, and glaciers careened down the mountainside, leaving a scarp 700 meters (2,297 feet) high, 1 kilometer (3,281 feet) wide, and just 20° off from vertical. All of that stuff had been keeping the lid on the cryptodome and its hydrothermal system. Now the pressure was off. And all of those gasses that had been kept down were now free to get out.

They didn’t go immediately. It took almost twenty seconds for the blast to begin after all that volatile material found itself freed. It’s possible the cryptodome and its hydrothermal system weren’t yet completely exposed, and expanding gasses might have been working their way through the remains of the north flank towards freedom. But there are also some complicated fluid dynamics to contend with. Even if the cryptodome had been instantly not-crypto, the blast would have taken some time – upwards of at least ten seconds – to form. A rarefaction (expansion) wave had to propagate, water needed to flash to steam, and dissolved gasses begin exsolving (coming out of solution), before an expansion wave involving more than one phase got round to propelling vapor and bits of volcano out.

This is all a complicated (yet greatly simplified) way of saying: water flashing to steam and gasses released from confinement blew the cryptodome apart.

There’s still some debate over whether the magmatic gasses within the cryptodome or the steam in the hydrothermal system caused the blast. The fact that so much of the dacite cryptodome got blown out suggests that its own gasses were major contributors. Regardless of which set of volatiles got things moving, once steam, magmatic gasses, bits of dome, and appreciable chunks of Mount St. Helens not stripped off by the landslide blasted through the base of the landslide scarp while more erupted from the top. Mind you, the landslide scarp wasn’t an immobile feature: it was slip-sliding down as block #2, leaving plenty of room for the expanding gasses to escape – sideways.

Diagram of the landslide (green) and directed blast (red) that occurred during the first few minutes of the eruption of Mount St. Helens, May 18th, 1980. Image courtesy USGS.

Diagram of the landslide (green) and directed blast (red) that occurred during the first few minutes of the eruption of Mount St. Helens, May 18th, 1980. Image courtesy USGS.

This is not usual behavior at volcanoes. But gasses that have been confined to a small space want to be in a large one, and they are not big on protocol. If a landslide leaves an exit in the side of a mountain, a lateral blast is the way they’ll go. Things were merely sonic to begin with, but as the blast reached the open air, it expanded supersonically. Fragments of old rock, hot chunks of the dome, and debris picked up on the way formed a roiling, boiling, dark gray cloud. Going up, gravity worked against it; going down, what was left of the ground interfered – but laterally, it found its way clear. It expanded more than 90° around the vent and sped down the mountain at speeds exceeding 600 km/h (373mph). In the valleys of the North and South forks of the Toutle River, the atmosphere was about to decide the fate of people who had, only seconds before, been enjoying a beautiful May morning.

Mount St. Helens in May 1980, after the debris avalanche and directed blast that removed her summit. Image courtesy USGS.

Mount St. Helens in May 1980, after the debris avalanche and directed blast that removed her summit. Image courtesy USGS.

Previous: Interlude: “Lateral Blasts of Great Force.”

Next: The Cataclysm: “That Whole Mountain Range Had Just Exploded.”

References:

Lipman, Peter W., and Mullineaux, Donal R., Editors (1981): The 1980 Eruptions of Mount St. Helens, Washington. U.S. Geological Survey Professional Paper 1250.

Special thanks to Helena Mallonee of Liberty, Equality, and Geology for use of her photo; and Lockwood DeWitt of Outside the Interzone for an excellent description of what the gasses were up to before and during the blast.

 

Previously published at Scientific American/Rosetta Stones.

Sunday Song: Assholes

So last week saw us treated to Elan Gale’s made-up saga, in which a woman annoyed people and he, Bwave Hewo, descended from the dizzying heights of being responsible for shit-sandwich television such as The Bachelor and proceeded to demonstrate how he believes that bullying sick women will make our social ills go away. Also, he seemed to have some idea he was doing the staff being bawled out by his imaginary woman a favor.

This is wrong on so very many levels.

Firstly: The fact he did this as a little light entertainment/publicity stunt on a holiday weekend shows he’s a first-rate shithead – as if we couldn’t already guess that from his teevee programs.

Secondly, as a thought problem, it sends the message that in these situations, asshole behavior + even more asshole behavior = harmony. This math does not work in the world outside Mr. Gale’s head.

Thirdly, Mr. Gale has set a terrible example for his followers, who now believe it’s heroic to be a misogynistic asshole to random women in unflattering pants and medical masks. His situation may be fiction, but life often imitates art (or piss-poor versions thereof), and we humans do take lessons and morals from stories. So do expect an uptick in asshole behavior from onlookers in all sorts of tense situations, plus much tweeting about what Bwave, Bwave Hewoes they are. Thanks to you, Mr. Gale, the world has just become that much more measurably worse.

Fourthly, even his stated objective fails: he claims to want to make things better by punishing a woman for being an asshole to staff. And I’m sure most of us agree that it would be nice not to reward assholes. However, as a person who has worked in all manner of retail, customer service, and technical support fields, I can tell you that having one asshole customer poked and prodded and annoyed by another asshole customer only makes the situation far worse for the poor staff member caught in the shit-flinging. More shit is sailing, and the original asshole now has a hemorrhoid. How happy is your asshole when it’s got one of those? How much more miserable does it make you? Yeah.

 

Image is of a cat smacking a small dog in the face. Caption says, "Good day, sir. I said GOOD DAY!"

The Elan Gale school of politeness.

Put it like this: if I were a zookeeper being harassed by a rather irritated tiger at feeding time, the last damn thing I need is some dumbshit in the audience deciding that what would really help the situation is to start pelting it with rocks. One or both of us is likely to get mauled, the poor tiger will feel completely justified as well as infinitely put out, and there’s no way the situation’s going to end happily for anyone except those who like their visits to the zoo to include bloody chunks of flesh being flung every which way.

So, fans of the Elan Gale method of making service people’s lives better: don’t. Just don’t. Sit down, shut the fuck up, and let the professional (helpful hint: this is not you) handle the situation. If this isn’t exciting enough for you, please go find a therapist who can explore the reasons why you may be such a terrible person and help you modify your behavior to become less of one.

And if you really want to help? Try gently defusing the original asshole. Or wait until that asshole has departed, and give the staff member some sympathy.

Now let us have some songs that rather perfectly describe Mr. Gale and his ilk.

Interlude: “To Paradise With Pleasure Haunted With Fear”

A serene terror loomed outside my schoolroom windows.

Mount Elden from a classroom window at Christensen Elementary School, Flagstaff, Arizona. Image courtesy Rocky Chrysler.

Mount Elden from a classroom window at Christensen Elementary School, Flagstaff, Arizona. You have no idea how delighted I was to find someone else who enjoyed the same view. Image courtesy Rocky Chrysler.

I went to school at the foot of a mountain made of dacite, the same kind of magma that blew Mount St. Helens apart. If I’d known that then, I probably would have had to change schools. I’d seen the eruption on television and read about the destruction in Marian T. Place’s excellent book. I already spent an inordinate amount of classroom time watching Elden for the slightest sign of steam, and that was back when I thought it was a shield volcano and the school would merely be buried in streams of red flowing lava, just like unfortunate structures in Iceland or Hawaii. I’d probably have come undone if I’d thought it would explode. I had a volcano phobia.

But I adored what I feared. I might go to school believing Mount Elden would suddenly awaken and kill us all, but I loved it. When we hiked to the top of it in sixth grade, I loved touching its boulders. When we drove past its crags on the way to the mall, I’d stare into them and look for the eagles living amongst the cliffs. And I only really feared that great lump when we watched videos of erupting basaltic volcanoes; the rest of the time, it was my quiet companion, and while it might turn deadly at any second (so I believed – after Mount St. Helens, I never believed people when they said something was extinct), it wasn’t any worse than the horses we owned, who were, after all, just as lovable and threatening.

Mount Elden, Flagstaff, AZ. Image credit Cujo359.

A wee panorama of childhood volcanoes. Mount Elden dominates the picture, a large exogenous dacite dome. One of the younger cinder cones of the San Francisco Volcanic field is being quarried in the foreground. The San Francisco Peaks peek out from behind Elden at the right. Image courtesy Cujo359.

Mount Elden was a mild sort of fear; I indulged fantasies of it destroying us all more from boredom than conviction. The mountain that truly frightened me was the stratovolcano that loomed behind it.

San Francisco Peaks seen from Bonito Park, Sunset Crater Volcano National Monument.

San Francisco Peaks seen from Bonito Park, Sunset Crater Volcano National Monument.

In this view, we’re standing on lahar deposits from that very mountain. It looks like a range of peaks, with the highest, Humphreys, reaching 12,633 feet (3,851 m) into the sky. But that is a single massive mountain, one stratovolcano, which lost an enormous chunk. Glaciers? Explosion? Sector collapse? I’ve just obtained a paper that promises to answer that question. But I remember the day I stood at Bonito reading the sign that said the meadow was a lahar from the Peaks, and turning around to look into the caldera, and feeling a chill run right through me as its resemblance to Mount St. Helens became clear.

I’d been terrified of it since learning it was a stratovolcano as a child. When you first learn what a stratovolcano is by seeing one explode all over the place on teevee, you tend to look a bit askance at the one visible from your backyard. But I grew up with that vista, volcanoes framed in the sliding glass doors. I camped on those peaks (watching for imminent signs of doom all the while). I’d have repeated dreams of them erupting, of fleeing for my life as pyroclastic flows roared down the mountain, of fires started by blazing hot ejecta. Then I’d wake up and go stand in the doors, drinking them in. They were the most beautiful peaks in the world to me. When we moved away from Flagstaff, I felt relieved we wouldn’t have to evacuate due to an eruption – and bereft, horribly homesick for my peaks. When we drove into Flagstaff, I’d have my eyes fixed on the horizon, waiting for the first glimpse. “Hello, ‘Frisco,” I’d whisper. “I’ve missed you.” It’s a ritual I still repeat when I return home.

You learn to live with the fear. You learn to enjoy the beauty while you can. You can firmly believe, in the same moment, that there is no more perfect place to be than at the foot of this magnificent mountain, and that you should be anywhere but here. You make fretful plans for escape, you watch for the slightest sign of activity, you run disaster scenarios in your mind – and you drive up to the top on a day when you need peace and calm restored. You go there to renew your soul and learn to accept your inevitable meeting with Death. You tell your family that you’re so outta that city the instant the volcano wakes up. You explain to them the difference between dormant and extinct, and you describe with relish all of the terrible ways to die in an eruption. You assure everyone around you that you will never in a million billion trillion years set foot on an active volcano. This is what you do when you have a mild volcano phobia, but have grown up in the shadow of the Peaks.

Then you take it into your head to move to Seattle.

Mount Rainier, seen from near Federal Way, south of Seattle, Washington.

Mount Rainier, seen from near Federal Way, south of Seattle, Washington.

Well, sure, the city’s surrounded by active volcanoes, but hey – they’re monitored! We’ll have plenty of warning before they blow! And I’m renting, not buying, so I can flee any old time I like. I can be back in the Valley like that. Stepmom and Dad have a spare bedroom.

And it’s not like I’m going to actually traipse around one of them while they’re erupting, right? Not me. I’d never do that. Except, you know, we went to Mount St. Helens that one time when it was actually in the middle of an eruptive phase, only we didn’t know, and I looked into the caldera and saw steam rising from the dome. I saw the parking lot filled with little burn marks from hot ejecta. I saw ash-covered slopes.

And I wasn’t afraid.

Mount St. Helens seen from the Hummocks Trail.

Mount St. Helens seen from the Hummocks Trail. All of this lumpy terrain is from the debris avalanche: we’re standing on what used to be the top of the mountain.

Fear became fascination. I still harbor a healthy respect for what these fire mountains are capable of, and I’m still in my parents’ spare bedroom in half a heartbeat with the cat and whatever possessions I could throw in the car at five minutes’ notice if Seattle looks to be targeted for annihilation, but I’ve learned enough now not to panic. Knowing these volcanoes intimately doesn’t make them feel any safer. It just makes me feel more capable of assessing their threat, and more accepting of the fact that I might be wrong. I’m willing to take that risk now. As long as it’s not Glacier Peak waking up, I’d like to stay for the show.

I love my fire mountains too much to leave them.

Three Sisters as seen from the Lava River Trail, Dee Wright Observatory, Oregon.

Three Sisters as seen from the Lava River Trail, Dee Wright Observatory, Oregon.

I’ve walked flows five hundred years younger than the ones at Sunset Crater, which at less than a thousand years old were uncomfortably recent to my childhood mind. The stratovolcanoes visible from there are far younger and much more restless than my quiet old Peaks.

I’ve stood on the rim of a volcano that blew far more catastrophically than Mount St. Helens.

Crater Lake from the Phantom Ship Overlook, near sunset. 7,700 years ago, Mount Mazama emptied its magma chamber in a humongous eruption (that's an official scientific classification), and collapsed into itself, leaving a hole in its heart that filled with a lake that is the bluest blue you've ever seen.

Crater Lake from the Phantom Ship Overlook, near sunset. 7,700 years ago, Mount Mazama emptied its magma chamber in a humongous eruption (that’s an official scientific descpription), and collapsed into itself, leaving a hole in its heart that filled with a lake that is the bluest blue you’ve ever seen.

I’ve walked the basalt flows of a cinder cone that’s virtually the twin of the one I grew up with, although it’s six thousand years its senior.

Lava Butte, Oregon, and its associated lava flow.

Lava Butte, Oregon, and its associated lava flow.

I’ve stood at timberline on a volcano that seems made of nothing but rubble and hydrothermally altered rock.

Mount Hood from near the Timberline Lodge. It's very, very unconsolidated, and has a horrible habit of having major bits wash down and wipe out roads. But it's pretty!

Mount Hood from near the Timberline Lodge. It’s very, very unconsolidated, and has a horrible habit of having major bits wash down and wipe out roads. But it’s pretty!

I know them intimately now. I know their greatest danger doesn’t always come from their eruptions, but by bits of them failing catastrophically. Sector collapses can happen without eruptions; lahars can wash down slopes with no warning, since it’s not just eruptions that cause them. When you’re near a volcano, you’re always seconds from catastrophe.

I find them irresistibly beautiful. “Yet do I fear thy nature,” as Lady Macbeth said. My paradises have always contained that element of danger that demands respect. Maybe I love them so much because I can’t take them for granted: what they are today is not what they will be tomorrow. It’s in their nature to blow up, to fall down, to intersperse long periods of serene beauty with utter disaster. It’s wise to approach them with a measure of awe and a dash of respectful fear.

Moi atop Paulina Peak, Newberry Crater, Oregon. This is a high, craggy bit of a long and low shield volcano that contains one of the greatest obsidian flows ever. I'm also surrounded by stratovolcanoes up here. It's outstanding.

Moi atop Paulina Peak, Newberry Crater, Oregon. This is a high, craggy bit of a long and low shield volcano that contains one of the greatest obsidian flows ever. I’m also surrounded by stratovolcanoes up here. It’s outstanding.

Tell me about the geologic processes you love and fear.

Credits:

The title of this post is from the song “She is My Sin” by Nightwish. Larger versions of most of these volcanoes are available in my Flickr set; the Mount Elden schoolroom photo is here.

 

Previously published at Scientific American/Rosetta Stones.

Interlude: “Lateral Blasts of Great Force”

One of the most surprising aspects of the May 18th eruption of Mount St. Helens was the devastating lateral blast that ravaged such a large area. We’ll be spending the next few posts on that subject. It’s a complicated aspect of a very complex eruption, so before we dive in, let’s have a look at historic lateral blasts, what we knew before the whole side of Mount St. Helens blew out, and some of what we learned from her.

Lateral blasts weren’t completely unknown before 1980. In 1888, Bandai-san in Japan experienced a catastrophic eruption that removed 1.5 cubic kilometers (.36 cubic miles) of its summit. Its former Fuji-like summit was reduced to a shattered remnant – much like another volcano we’ve become intimate with. Imperial University of Tokyo geologists Seikei Sekiya and Y. Kikuchi thought the deposits left at base of Bandai-san’s north slope were the result of a landslide; Soviet volcanologist G. S. Gorshkov put them down to a directed blast. Could it have been both? Mount St. Helens tipped us off to the possibility that such blasts were very much related to landsliding: an earthquake knocks an unstable slope loose, the resulting landslide depressurizes a magma chamber (and/or hydrothermal system?) beneath, and boom.

Ukiyoe depicting 1888 Eruption of Mount Bandai, Japan.

Ukiyoe depicting 1888 Eruption of Mount Bandai, Japan. Image courtesy Wikipedia.

In 1956, Bezymianny volcano on the Kamchatka Peninsula exploded in 1956 – an eruption Gorshkov classified as “really gigantic.” And it was – the eruption destroyed a large part of the volcano. Gorshkov’s Figure 16 shows the pre-eruption outline superposed over the post-eruption edifice. Fans of the Mount St. Helens series should find this eerily familiar.

Bezymianny volcano, Kamchatka, current and former summit

Bezymianny volcano after the explosion of March 30, 1956 (photograph taken in April, 1956) – black line shows outlines of the volcano before the eruption. Fig. 16 from Gorshkov’s “Gigantic eruption of the Volcano Bezymianny.”

After May 18th, 1980, volcanologists looked back on Bezymianny and found the destruction there making a certain amount of sense.

Shiveluch, also in Kamchatka, erupted violently in 1964. Gorshkov wrote a seminal paper on the blast entitled “Gigantic Directed Blast at Shiveluch Volcano (Kamchatka),” referenced often by USGS geologists as they worked to make sense of the events at Mount St. Helens. The lateral (directed) blast here removed several domes painstakingly built by the mountain in previous eruptive periods and left a shell.

Shiveluch volcano before and after

Gorshkov’s Figure 6 from “Gigantic Directed Blast at Shiveluch Volcano (Kamchatka)”. A – Domes of Crater top before the eruption (in 1949), B – crater of 1964. Both pictures are made from the same point. Main top on background.

“It is necessary to add,” Gorshkov wrote, “that the formerly picturesque volcano foot having been rich in animals and vegetation, turned into a barren stony desert, covered with thousands of large and small hills.” He could have been describing the devastated area at Mount St. Helens.

The two lateral blasts, happening within less than a decade of each other on the same peninsula, led Gorshkov and his fellow geologists to define directed blasts as a new kind of eruption, and caused volcanologists to take a closer look at previous eruptions that hadn’t been formerly understood as lateral eruptions.

Geologists even found evidence of previous lateral eruptions at Mount St. Helens. Crandell and Mullineaux noted in their hazard assessment that “such blasts often are associated with the formation of a volcanic dome, and they generally only affect the side of the volcano on which the dome is being erupted.” They advised that lateral blasts could affect areas out to at least 10 kilometers (6.2 miles). They were very aware that Mount St. Helens was capable of producing a directed blast, perhaps even a sizable one – but no one predicted the scale of what she ultimately unleashed. The only confirmed lateral blasts she’d been responsible for previously had happened just over 1,000 years previously, and those were just two piddly things not even a tenth of the size of her May 18th extravaganza.

There were other directed blasts at other volcanoes – Lassen Peak in California in 1915, for instance, where a lateral blast destroyed a large swath of the northeast slope, and Mount Lamington in Papua New Guinea, where an eruption similar in type but smaller in size to Mount St. Helens occurred in 1951 – but they all had something else in common: their directed blasts, for various reasons, weren’t nearly as well observed. Mount St. Helens, however, was crawling with geologists, bristling with sophisticated equipment, and festooned with photographers. Her eruption happened on a sunny morning on a clear day near a populated area. And that lateral blast became perhaps the best-documented, most closely-studied directed blast in history.

This twisted stump is all that remains of a 100-foot-tall red fir tree snapped off in Lassen Peak’s May 1915 eruptions. During the eruptions, high-speed avalanches of hot ash, rock fragments, and gas (pyroclastic flows) and huge mudflows of volcanic materials and melted snow (lahars) swept down the northeast flank of the volcano, flattening many acres of mature forest (see photo on left by Benjamin Loomis; courtesy National Park Service). Some of the lahars traveled more than 12 miles from the volcano, destroying homes along Hat Creek.

This twisted stump is all that remains of a 100-foot-tall red fir tree snapped off in Lassen Peak’s May 1915 eruptions. During the eruptions, high-speed avalanches of hot ash, rock fragments, and gas (pyroclastic flows) and huge mudflows of volcanic materials and melted snow (lahars) swept down the northeast flank of the volcano, flattening many acres of mature forest (see photo on left by Benjamin Loomis; courtesy National Park Service). Some of the lahars traveled more than 12 miles from the volcano, destroying homes along Hat Creek. Image courtesy USGS.

Geologists were overflying the mountain the instant it erupted, were photographing and flying around it throughout the eruption, and were on the ground before the ash had a chance to settle. They dug into the fresh deposits, documented and sampled and measured, took eyewitness statements, studied their photographs, and collected readings from a variety of instruments that had recorded the whole event. They could follow the whole sequence in series of photographs, correlate those photos to observations on the ground, and figure out just what causes volcanoes to sometimes blow out laterally.

Mount St. Helens also provided a laboratory where we learned how to recognize the eruptive products of directed blasts. One of the major axioms of geology is “the present is the key to the past.” When it comes to volcanoes, the past is also the key to the future. But you have to know what you’re looking at in order to decipher what those deposits are trying to tell you. The May 18th directed blast left plenty of deposits for geologists to study. They provided a nice compare-and-contrast that helped geologists understand the difference between classic pyroclastic surges and this bizarre horizontal eruptive style. Knowing what to look for would help geologists recognize similar landslides, now called sector collapses, at hundreds of other volcanoes.

Mount St. Helens blast-deposit section showing four units: a, basal; b, surge; c, pyroclastic flow; and d, accretionary lapilli. Section located north of Elk Rock about half way to Hoffstadt Creek. Shovel for scale. Cowlitz County, Washington. 1980. Figure 227, U.S. Geological Survey Professional paper 1250.

Mount St. Helens blast-deposit section showing four units: a, basal; b, surge; c, pyroclastic flow; and d, accretionary lapilli. Section located north of Elk Rock about half way to Hoffstadt Creek. Shovel for scale. Cowlitz County, Washington. 1980. Figure 227, U.S. Geological Survey Professional paper 1250. Image courtesy USGS.

We’re now far more aware that those big, beautiful stratovolcanoes have a distressing tendency to fall down in major ways, and don’t always blow up so much as blow out. This helps us understand the hazards we face as more people live and play near and on these dangerous but captivating mountains. The lessons we learned from Mount St. Helens help us save lives.

Previous: The Cataclysm: “One of the Most Dramatic Mass-Movement Events of Historic Time.”

Next: The Cataclysm: “A Sudden Exposure of Volatile Material.”

References:

Crandell, D. R., and Mullineaux, D. R., 1978: Potential hazards from future eruptions of Mount St. Helens, Washington. U.S. Geological Survey Bulletin 1383-C.

Gorshkov, G.S. (1959): Gigantic eruption of the volcano Bezymianny. Bulletin Volcanologique, ser. 2, v. 20, p. 77-109.

Gorshkov, G.S. and Dubik, Y.M. (1970): Gigantic Directed Blast at Shiveluch Volcano (Kamchatka). Bulletin Volcanologique, v. 34, p. 261-268.

Lipman, Peter W., and Mullineaux, Donal R., Editors (1981): The 1980 Eruptions of Mount St. Helens, Washington. U.S. Geological Survey Professional Paper 1250.

 

Previously published at Scientific American/Rosetta Stones.