Cataclysms on the Columbia

The Great Missoula Floods

John Eliot Allen, Marjorie Burns, Scott Burns

• Verlag: Ooligan Press
• Jahr: 2019
• ISBN:
  9781932010466
• Auflage: 2
• Thema: Scienze fisiche
• Thema: Geologia e scienze della terra

Cataclysms on the Columbia tells two stories. One follows geological research that challenged the scientific paradigm of the early 20th century, and the other chronicles the result of that research: the discovery of powerful prehistoric floods that shaped the Pacific Northwest. The cataclysms at the end of the last Ice Age left a scabland of buttes, dry falls, and rocky gorges, but it took the detective work of geologist J Harlen Bretz to prove it to the world. His lifetime of research and unshakeable belief changed geology forever.

PART I:

THE WORLD OF GEOLOGY

1

THE LIVING, CHANGING EARTH

A word is not a crystal, transparent and unchanged, it is the skin of a living thought and may vary greatly in color and content according to the circumstances and the time in which it is used.

—Justice O. W. Holmes

Why should anyone care for geology? There’s no life in it, just rocks, things that stay put for the most part. Only a landslide, a sloughing of mud, or a river swelling beyond its banks and rolling a rock here or there can make much of a difference. Well, admittedly, there are volcanoes, flows of lava, earthquakes. These do shift the landscape around a bit, but for most of us such events seem more than a little improbable, like dragon sightings in the county next door. Even for people in the Northwest, the eruption of Mount St. Helens all too easily became something we saw for a while on TV. So when we meet a rock, we don’t usually think much of it. It’s a leftover, a fragment, a chunk of something else, the rubble and scrap of bigger rocks.

We joke about rocks. Some years back pet rocks were in vogue: “easy on the furniture, non-shedding, guaranteed housebroken, may be fed on milk (it comes in quartz),” and so on. And this joking is understandable. Rocks as symbols of affection are amusing; and the prototype of the rock-lover, the rock hound, is—well, let’s admit it—faintly comical.

But perhaps we’re being unfair. Rock hounds are only the hangers-on, the groupies to the profession. What about the trained geologist? What about the degreed and practiced geological specialist? Surely some greater aura surrounds the professional, not perhaps an aura of romance and awe-inspiring wisdom but some quality of expertise, something that commands our respect, if not our emulation. And, yes, there is a special quality to the geologist. There’s a lean, sun-parched leatheriness to most that sets them apart from other professionals. Even in the tweediness of an academic setting, the geologists are the ones with field boots disrupting the set of their cuffs.

Look closer at those boots. Therein lies (literally and figuratively) the understanding of the geologist. The geologist has roots in the earth; the geologist admits the clay in human beginnings. The geologist is a watchdog with an eye to earthly hazards as well as an explorer, a seeker of oil or water or metals; but the story of geology is as much a story of intrigue and polemic dispute as it is of boot-paced exploration and practicality. Geology looks for the plot, the unfolding; it’s the epic of sciences, the grand story of it all, the moving picture of the earth’s history. Geology is not just a rock sitting still. It’s process; it’s change; it’s transmutation. But we poor, quick-lived individuals—the drudges of the day—can’t see that the tale is going on at this moment, that we’re living within it. Like seasons to a mayfly, geological changes are outside our timeframe and virtually outside our comprehension.

“Well,” you say, “that still doesn’t make it much of a bestseller, does it? Process isn’t much of an audience-grabber. Where’s the sex and violence?”

Sex and violence? It’s there, bigger and more screen-filling than ever you imagined. Doubters, skeptics! We’re living, breathing, and walking around on a vast, changing, growing mass whose story—like the mating, birthing, and death of giants—makes our own small lives look puny indeed.

Our ancestors knew; they saw passion in the birth and death of rivers and mountains, oceans and worlds. They gave us the gods: gods-as-stars, and gods-as-planets, and gods of chaos, forces, and elements. “In the beginning” (said the Pelasgians in the third century BC), “Eurynome, the Goddess of All Things, rose naked from Chaos. … She danced toward the south, and the wind set in motion behind her seemed something new and apart. …Wheeling about, she caught hold of this north wind, rubbed it between her hands, and behold! the great serpent Ophion.” She danced “wildly and more wildly, until Ophion, grown lustful, coiled about those divine limbs and was moved to couple with her.” From this union came the sun, moon, and stars, the earth with all its complexities, and the distant planets, each to be ruled by a Titan and a Titaness.

Human beings, however, have never agreed upon any one version of the truth. Others say it was Uranus who fathered the Titans upon Mother Earth and that she, in anger, persuaded them to attack their father. Led by Cronus (who became “Chronus” or “time” for the Greeks) they did so; and coming upon Uranus as he lay sleeping, they castrated him with a sickle.

This sense of passion and violence in the creation and shaping of the heavens and earth is not merely a peculiarity of our ancestors. Even today, geologists tend to write about their subject as though it were, somehow, made up of living, changing, and at times even willful beings bestowed with emotions, purpose, and human features. The geologist’s descriptive vocabulary is fraught with terms of violence, invasion, and resistance. Or it borrows from human physiology or from structures and buildings and common household items.

Glaciation “invades,” “destroys,” or “dominates.” Floods, unable to “tolerate” normal water courses, “vigorously attack” or “overwhelm.” Landscapes are “gashed,” “broken,” “sacrificed,” or “overthrown,” as though injuries were deliberately inflicted. Topography can be “plucked,” “scoured,” and “scarred.” Hills are “unyielding,” and ridges “strongly expressed.” Rivers are “fed” or “starved.” Mountains, waterways, and other landforms have “heads,” “mouths,” “lips,” and “skin”; “arms,” “flanks,” “feet,” and “toes”; and those of you who have not checked the meaning of the Grand Tetons should do so. There are “floors,” “benches,” “basins,” “entrances,” “walls,” “beds,” “pillows,” and “blankets.” Even a gravel fill can be “intimately related” to a geological process, and all of it can be spoken of in terms of “birth,” “maturity,” and “decay.”

What we get, then, if we pay attention to geological terminology, is a scrambling of human-related words and a sense (subliminal but effective) that the earth is in some ways alive. To feel this, to see the earth in this light, is to give ourselves the vantage point of gods (or geologists), to step beyond the limits of our years and sense the quickening rhythms of a world.

2

DETECTING THE CLUES TO THE PAST

… every geological phenomenon is determined by an almost immeasurable number of variables, horrifying in their complexity and in the number of their interrelations. Every formula that uses a limited number of variables is therefore but an extreme simplification.

—Martin Gerard Rutten, 1955

This is a story staged in two time periods. In more than one sense, it’s a detective story involving the reconstruction of an event that occurred over 15,000 years ago and “one man’s effort to change the verdict” in our own time. There is no human crime involved, no plotted and executed murder. Nonetheless, the key events of this drama are based on catastrophes of such magnitude that understanding the mystery continues to be a prime concern for those who come upon the scene today.

It is not unusual to think of geology in terms of detective work. To a large extent, geology is routinely a matter of investigation and testing of hypotheses. This in itself does not make geology different from most other sciences; but like criminal investigation, geology deals with events that have already taken place and works to reconstruct the order and cause of these events, using methods more speculative than testable. Physicists, chemists, and biologists can rely heavily upon laboratory experiments; astronomers and geologists, for obvious reasons, cannot. Beyond the analysis of moon dust or other more earthly rocks, there is less of their subjects that will slip neatly into a Petri dish.

Though, ideally, geological discovery is a continual play-off between speculation and proof, between the ivory tower and the field, ultimately the site itself must serve as the final check. This means getting out and clambering around on the earth (or the moon!). Like the detective, then, the geologist must sooner or later turn from laboratory interpretation (or from sweeping overviews and armchair speculation) to examine once more the “scene of the crime.” A rock proven by lab tests to contain gold or oil does not necessarily mean that the area it came from is rich in these materials, any more than a trace of arsenic in a corpse is proof that the host at last night’s dinner party ought to be arrested. It’s a matter of puzzle work, of using all available techniques to rebuild the scenario. Think of the paleontologist confronted by a scattering of bones. From these incomplete bits and pieces and disconnected parts, an animal is to be reconstructed. There’s no stomach, no flesh, no hair; and yet—from knowledge of how present-day animal species work—a handful of ancient remains, filled in with a generous supply of plaster, can lead to a skillfully conjectured and convincing specimen.

When geologists attempt to reconstruct the history of the earth, they too work this way, with random parts and puzzle pieces glued together by an understanding of geological process. It requires a sharp eye for unusual or easily overlooked clues and a sharp mind that can imaginatively and intelligently conceive of how the formation under study might have come about. (To this, add sturdy legs and boots.)

And there’s more. Like any good detective, the geologist must not allow love of a particular pet theory to override other working hypotheses. The geologist must consider multiple possibilities and then work to disprove them, one by one. The simplest explanation that holds up under repeated attempts to discredit it is the theory favored. (In the trade, this is known as “Occam’s razor” or “the principle of parsimony.”)

Notice too that the term “hypothesis” is used more often than “fact.” Though there are certain well-established facts known to the science, geology by its nature must remain full of mysteries. It’s hard enough to make a criminal confess all the details and impossible to make a landform do so. Conceptions are therefore likely to be more a matter of wise conjecture than of mathematical certainty, and verdicts are mostly reached by consensus. In geological matters, this nearly always means publication, so that other responsible scientists, operating much like a jury, can work toward some form of agreement. At times, however, dispute becomes hot and lengthy, and continual “retrial” begins to seem all too inevitable. It is then that courtroom-like hostility and Perry Mason theatrics creep in. Unpopular theories may be discredited without fair consideration; pertinent information may be withheld in order to maintain a preferred line of reasoning; and thinly disguised methods of personal attack may well infest the proceedings. It happened with plate tectonics, and it happened with the Missoula Floods.

PART II:

THE BRETZ SAGA

3

EARLY DAYS

We crack the rocks and make them ring,

And many a heavy pack we sling;

And run our lines and tie them in,

We measure strata thick and thin,

And Sunday work is never sin,

By thought and dint of hammering.

—A. C. Lawson, “Mente et malleo,” 1888

The geological detective tale that developed over Bretz’s Flood Controversy is a tale of such sustained intrigue and epic proportions that its unfolding makes most fictional mystery plots seem trite in comparison. The two parts, both “crime” and “trial” (both the floods themselves and their interpretation over 15,000 years later) are impressive in their own right. They merge, however, into one storyline through the work of J Harlen Bretz, the man who made their study a main focus of his early work and discovered the existence of what he called the Spokane Floods. In our mystery novel analogy, it is Bretz who plays the role of the dissenting but ingenious detective, the man who continues his pursuit of truth virtually unassisted and against all odds.

J Harlen Bretz (Figure 3-1) spent over four decades defending his theories on what are now known as the Missoula Floods before they were generally accepted by the scientific community. By then he was over 80 years old and, though limited in his ability to do field work, still mentally active. (He remained alert and productive until his death in 1981 at the age of 98.) His gift was the ability to take information and see it in a new light and then to check and recheck again and again to assure himself that his conclusions were correct. Bretz was above all a questioner and a thinker. And this, says his daughter, explains his reputation for rarely smiling. It was not from lack of warmth or humor, but simply that Bretz’s mind was likely to be elsewhere.

Figure 3-1. J Harlen Bretz, in a photo taken around 1910.

The early details of J Harlen Bretz’s life are relatively simple, but somewhere in those early years he gained the insatiable curiosity and enduring stubbornness that later made him the man to recognize and document the Spokane Floods. He was born in Saranac, Michigan, in 1882, the eldest of five children. “In my line, all had been farmers for a time at least,” Bretz wrote about his boyhood. “As I grew older, my father Oliver thought that I might make a good stock farmer. I never agreed, went care-free through early boyhood and first encountered something far better, a small school library open only on Saturday afternoons.”

From this came Bretz’s first scientific fascination: astronomy. He built an observation platform around the central chimney of his “father’s big two-storied red barn” and set himself to learning the names of stars, identifying constellations, and keeping observation notes. “But my first real discovery,” Bretz claims, “was that I never could master the mathematics in astronomy.” This shortcoming, the inability to work well with figures, was one that remained with Bretz throughout his life and one that he jokingly liked to blame on an early head injury received from falling out of bed as a young child.

However much his father may have wished him to become a farmer, it is nonetheless clear that learning was encouraged in Bretz’s family. Not only were his parents supportive of his astronomical hobby, but shortly after Bretz h...