Just give me one thing I can play for.
Disco boys on bicycles.
So what if too many times we have been here, both
Poetic Retrospective
The Weather votes for Kelly Clarkson.Like other tombs, this one is quiet, except for the living; a group of serious geology students out of the University of Washington. The class taught here today is named Volcanos and Glaciers of the Pacific Northwest: Geology 312, but, officially, in the University's course catalogue, it is listed as Geochemistry, a term that would take all the fun out it.
The class is taught by Dr. Tony Irving, a ready-looking naturalized Australian of about fifty. He is handsome, like Australians tend to be, and endowed with a salt-and-pepper-well-trimmed mustache and a penchant for jokes aimed at New Zealanders. His assistant -- a chiseled, Gen "X", rock climbing graduate student named Erik Reiner (who a few of us have begun calling "E-Rock") is along for the trip as well.
We are on a plateau, long since populated by farmers, studying the violence of one of one of modern history's most massive displays of destruction: the notorious Osceola Mudflow.
Walking through the valley, I am none the wiser of its recent fury -- the only evidence is buried beneath our feet. Sultry Mt. Rainier lurks behind us, a drape of a high cirrostratus cloud obscuring her peak.
If you are the type of person interested in killer mudflows, or "lahars" (the Malaysian term that has come to mean volcanic landslides) then you are no doubt familiar with the recent catastrophic event caused by Nevado del Ruiz -- a so called stratovolcano in Columbia, South America where more than 23,000 lives were swept away in an instant, crushed and drowned. If you are not the sort of person interested in mudflows and you are currently a resident living in the drainage basins of Mt. Rainer, perhaps it is time to become more familiar with this tragic event.
Colombia's highest peak, Nevado del Ruiz is located in the northern most tip of the Andes with a summit elevation reaching 17,680 feet. Amazingly, even though it is located only 300 miles from the Earth's equator, at the time of the event it was covered with 92 miles of snow and ice. Ice and snow are the fuel of a lahar, mixing with loose soil and sediment to set the landscape aflame in mud, splinters, and sometimes, if the conditions are just right, hot volcanic ash.
The professor asks us to recall the facts.
On November 13, 1985, at 9:08 p.m. an explosive eruption from Nevado del Ruizs crater generated a column of ash which sent a series of hot pyroclastic flows across the volcanos broad ice-covered summit. A pyroclastic flow is a fluidized mass of rock fragments and gases that move rapidly down a volcano -- like hot batter down the sides of a waffle iron. Yet, up to this point, there is no immediate danger, not in the classic way we tend to think of volcanoes. Even with scorching volcanic rock pouring down the slopes of Nevado del Ruiz, the eruption so far is common with the behavior of an active volcano; no big deal, the professor explains, at least not yet.
The debris being thrown from the volcano can only land safely in the vicinity of the crater and not as far away as the soon-to-be-doomed town of Armero along the Rio Lagunillas nearly 62 miles away. However, it is here that the catastrophe finds its genesis: 26 feet of pumice and ash melt the glacier and send a virtual tidal wave of mud and ash down the mountain. They may even have heard the ruckus that Nevado del Ruiz's made that night -- a distant rumble, miles away. It may have startled them and then, once the noise had faded and the real danger was on its way -- flooding through the valley, pealing back its skin, harvesting boulders, trees, logs, and assimilating them into a deadly brew -- the residents shrugged and lay again where they slept, or put away a dish or let in the family pet.... It is said that one in three people from town perished in the violent flood. As I look around the group, time and imagination keeps us at asafe a distance, but I still cannot fathom what that number must mean to the people of Armero. Many of the residents did not have time to run. They were buried alive in the room of their last chore, or in the beds that they last slept.
How I came to study geology with these students is a long story that can be compressed into the next sentence. I am a teacher myself and hope to learn more than cursory information about the tectonic history of my native state of Washington. At age thirty-six, if not for the professor, I am the oldest person on this trip. (There is one older gentleman who is a no-show today, a professor I think, who sits in the back of the room during lectures with a dour expression, raising his hand every-once-in-a-while to ask questions I never understand.)
Standing in the field, we are eager to learn form the geological duo -- the professor and his sidekick -- but, at the moment, the espressos and double-frosted cinnamon rolls we picked up in a town named Black Diamond need a bit more time to diffuse into our bloodstream. "Some of them held on to branches, or broken pieces of houses as they were carried away in mud with the constancy of concrete," the professor tells us. "This event caused volcanologist sto search their souls. If such a catastrophe can't be predicted, or at the very least, adequate warnings can't be given, then why are universities and government agencies like the United States Geological Survey in the business of studying volcanoes?"
A lahar on sultry Mt, Rainier could arrive with little or no warning. It would flood into a valley populated with nearly 150,000 people, an event that could make the 23,000 deaths caused by Nevado del Ruizs pale in comparison.
In fact, Science writer Blaine Harden reports that geologists have found an abundance of evidence to support that over the past 5000 years, many lahars have reached as far away as the Duwamish river in Seattle, nearly 75 miles away. A killer lahar would give residents little time to gather family into a car and head toward civil-emergency evacuation routes. Traveling at nearly 60 mph, a large lahar would bury the small town of Orting in nearly fifty feet of mud in less than an hour and then continue bowling down the Puyallup River Valley, suffocating, blasting though trees, zeroing in on the more densely populated areas of Sumner, Ashford, Elbe, Packwood, Randle, Greenwater, and Puyallup. All of these towns are in jeopardy.
Assuming that all hear the lahar alarm, residents could make it up hill quickly enough to avoid the mudflows. If all goes well, like it did at Maple Lawn Elementary School during a recent drill, then the children would make their 1.7-mile trek up the valley slope in 36 minutes. However reassuring a successful drill might be, our professor tells us dryly that the estimates of larhar times are as inexact as they are political -- just as disturbing, he explained, as a New Zealander counting sheep; winking, waving, and blowing kisses to each animal as he goes along.
Indeed, decisions regarding evacuation usually rest with local government officials, emergency managers or civil defense personnel -- decisions that carry enormous social and economic costs. Sadly, these issues are often resisted by the local community. Compounding the problem is a lack of productive communication between scientists, who attempt to predict a disaster, and pragmatic decision makers who must balance time and resources against danger. Repeatedly, volcanologists must assume the difficult role of explaining uncertainties about volcanic hazards to a public unfamiliar with its nuances. The process often leads to confusion, misunderstandings and strained relations between scientists and those responsible for public welfare.
"Go out and tell the world what youve learned," the professor laments and jests at once. "People dont take mudflows serious! They would prefer to die in burning lava! Exploding rock! Not some sissy mudflow!" He is right, of course, death by mud is not a very proud, sexy demise, though, you would be just as dead as dead.
A femme fatal, Mt. Rainier has a deadly secret. Or at the very least a surreptitious verity that could, similar to Nevado del Ruiz, lead to the deaths of many thousands. We learn more of her secrets after moving off the plateau, sticky fingers from the cinnamon rolls.
Off State Highway 410, a picturesque road traversing the White River, we stop at a vista and climb out of our vans. Amongst a gaggle of picture-snapping tourists, the professor unfolds a map the size of my son's blanket. "Look there," he says as cool as Australians do when they are bragging about the sting of one of their spiders. "That's where it began!" I follow his finger and find a white glacier, winking furtively. All across its massive, crumbling surface are blue crevasses, fragments of rotting rock and boulders the size of VW Bugs. At its base, it runs three hundred yards in both directions -- dwarfing the tourists and their cars. In the distance, the snow and ice tapers up the slope, ending in a single point near the rocky summit. "And it was here," he says loud enough for the tourists to hear, "without fire or molten earth, that the Osceola came rumbling down in an explosive fury."
I must admit, even after being dwarfed by this massing sheet of ice, I still felt quite safe. The very idea that something so enormous could move so suddenly transcended any point of reference that I had. Perhaps, if I stretched my imagination, I could conjure up the physical circumstance required to trigger such a catastrophe, but short of physics, I was left only an act of god. Such lack of imagination is dangerous, I know. The misperception that a something as powerful as a volcanic eruption is needed to activate a lahar is a famous and common error, one that drives volcanologists mad. They will tell you, happily, that in fact, there are three ways a lahar can be triggered, two of which happen without fire.
First, as in the case of Navado del Ruiz, hot tepha (scarring rock blasted from the throat of a volcano) caused unstable ice and ash to melt and then flood down the mountain's side. This is the more classic definition of a volcanic mudslide, and unfortunately the cause of much confusion. Since the other two do not involve heat in any way, many policy makers are complacent and the uninformed remain uninformed. The second type of event that can cause a lahar is an earthquake, which, consequently, may or may not be related to an active volcano. An earthquake makes intuitive sense: the earth trembles and sets loose tons of unstable deposits that cling precariously to the volcanos sides. The triggered landslide would, like a set of dominoes, carry with it whatever gravity has a predilection to carry: ice from glaciers, trees, rock, and soil. The third, and most common, is simply sparked by intense rainfall (during or after an eruption). Some of the largest lahars first began as a storm, setting loose tons of saturated hydrothermally altered rock.
As a matter of fact, it was as little as 500 years ago that Rainier last let loose a part of its rotting shoulder, sending mud roaring down the valley, killing, squashing, pulverizing. The rot near the summit is caused by gas inside the volcano, which degrades rock and turns it into more fragile, unstable clay.
Perhaps more counterintuitive than understanding the geophysics of lahars is attempting to grasp the only method of escaping them: NOT RUNNING AWAY FROM THEM! No, this does not mean that it is a good idea to sit down and let it overcome you in an existential reckoning -- rather, run! but be sure to move up the valley walls. This is essential in understanding how escape routes and emergency planning are formed. To use the bowling ball analogy; if one is caught in the gutter, to avoid being crushed, they can attempt to out run an encroaching ball (which is highly unlikely since, remember, lahars have been tracked at nearly 50 mph) or they can scramble up the sides of the gutter and move safely out of its path. No existential reckoning required, and survival preserved.
Lahars caused from an eruption can be predicted, but since lahars can also occur without warning, the challenge lies in knowing where to expect one and which roads will take you up the valley slopes and not further along its gutter. If people are informed of lahar activity in enough time, it is possible to escape physical harm by promptly climbing or driving to higher ground. In this picturesque and bucolic landscape, all along Rainers basins there are somber, modern looking signs which point to roads bisecting the valley: "Evacuation Route", they read, and all of them have arrows pointing out of the basin's gutter.
Which brings us back to the Osceola...
Following an eruption event 5,000 years ago, the Osceola mudflow (named after a Seminole Indian chief) was endowed by the near total collapse the mountain. Amazingly, Rainer was lowered nearly 9, 800 feet and the ensuing flood was so large that it raced at highway speed through White River Canyon, filled it with 600 feet of mud and then spread out to cover Enumclaw, where our trip began. Indeed, the Osceola mudflow created a mausoleum so large that even Egyptian tomb robbers would respectfully avoid it. Only the will power of Puget Sound, backed by its big brother the Pacific, stopped the monstrous flood. If another mudflow approaching this magnitude should hit again, it would dwarf the disaster in Nevado del Ruiz. Not just geographically -- but also in the amount of souls lost and buried in its crypt.
Like grave robbers, geologists are interested in the stratified layers beneath the surface. What they have learned is that since the Osceola mudflow, five additional eruptions have been recorded. And most recently, the "Electron Mudflow" (so named because of a nearby town situated near a hydro-electric dam) covered Orting (population 4,600) only 500 years ago. The layers are a reminder, tattooed into the landscape. When will the mountain again flex its muscle?
"This mountain is the most dangerous type of volcano," the professor barks, "it is a dormant volcano."
Once again we climb into the vans. My van is driven by E-Rock, who is telling another student that if he ever meets his Judeo-Christian God, he will ask him to explain the geology of the earth. A fair question, I think, if not a bit blasphemous. He releases the hand break and we catch up to the other van. A half-hour later we stop at a place on the itinerary labeled: "The Kautz Creek Mudflow".
Once again we are surrounded by tourists. Who could blame them? Behind us is a spectacular view of the Nisqually glacier. The cragged terminis of the lake-sized sheet of ice dips into an alpine valley. We, however, are faced the other direction, peering into a thicket of dead trees.
"What killed these trees?" the professor asks.
"Mudflows!" I shout.
"Yes, very good Antonio." He grins a little, "How?"
E-rock offers a clue.
"All these trees are upright," he says over the rush of a milk-colored stream, "attached by the roots." They were all dead, brown and long since drained of life.
"Compaction!" someone yells.
"Bingo!" the professor yells back.
In October of 1947 a small glacial outburst, caused by water stored up under the glacier was released by a torrential rain storm. Biblically, the water flooded out, gathered stones and other solids, mixed them into thick mud and eventually settled with a heavy sigh. I have seen trucks and other heavy equipment do the same thing to trees in my neighborhood, carelessly driving too close; compacting the soil, cutting off their ability to take in nutrients and water through fine root hairs. Here lay a forest, killed all at once. And this was a small mudflow?
We head back to Seattle, tired, crashing from the rollercoaster sugar high of Black Diamond cinnamon rolls. As we drive home through towns populating the valley, some of us poke fun at the people who would choose to live under such impending doom. It would seem that the human capacity to forgive and forget is often used on geologic threats. Perhaps E-Rock can ask his Judeo-Christian God why this is so.