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The Joy of High Tech

by

Rodford Edmiston

Being the occasionally interesting ramblings of a major-league technophile.

Please note that while I am an engineer (BSCE) and do my research, I am not a professional in this field. Do not take anything here as gospel; check the facts I give. And if you find a mistake, please let me know about it.

Science is a Process

Critics of science fall into three groups: Those who claim it is too rigid and resistant to new ideas (mostly the crackpots); those who claim it is too eagerly accepting of any new idea which comes along and ignores "traditional wisdom" (generally the fundamentalists); and those who use both arguments (usually politicians). What all three groups ignore is that true science - that is, modern analysis and description of nature through the scientific method - is a process, not a dogma. It is designed to be self-correcting, to encourage the questioning of precepts, but in a controlled, measured manner which rejects unsupported claims while accepting evidence contradicting long-held positions as long as it is presented properly. Ideally, personalities should play no part in this process, though unfortunately they often do. A good example of how the process works comes from the study of a particularly interesting bit of geography.

The Channeled Scablands are a region in the northwestern United States (primarily eastern Washington State, though related features extend into other states, and the prehistoric Lake Missoula, in Montana, turned out to be vitally important in understanding the Scablands) which possesses some astounding features. There are mammoth waterfalls with only a trickle of water going over them, down into deep pools with only a relatively small amount of debris in their bottoms. There are deep, wide channels with rectangular cross-sections (rivers normally cut V-shaped cross-sections and glaciers U-shaped ones). There are erratic boulders larger than most houses carried miles from their native rock and tossed like marbles by a petulant child to well outside streambeds. And many other features which resemble those left by a small stream in hard soil after a Spring flood. Only on a titanic scale...

There are ripples in silt which in such a stream as is described above would be at most a few centimeters high, but which here stand several meters from trough to peak. Scars high on the walls of deep channels are scour marks left by water. Such features could have been produced only by flow volumes and velocities associated with truly catastrophic discharges, and not by the slow erosion more common in places such as the Grand Canyon.

In the early Twentieth Century many geologists were aware of the Channeled Scablands but few even dared to put forward suggestions as to how they might have come about. This was a time when geology had only just gotten away from Bible-inspired catastrophism, instead espousing Uniformitarianism, a steady-state model in which things had always proceeded in the same way as we see now. But some features of our world require catastrophes to exist, and some of those catastrophes are very uncommon situations.

J. T. Pardee was one of the earliest modern geologists to explore the Scablands and write of it in professional journals. He was as puzzled as anyone else as to the cause of the features he discovered, venturing that some of them may have been due to ice-age glacial action. Even he admitted that this could not explain everything he saw.

It is worth going into these features in some detail, if only to exercise one's sense of wonder - not to mention one's sense of scale. The canyons have steep, terraced sides. (Note that these descriptions generally ignore the loose rubble which has accumulated since the features were formed.) The streams which flow in them seem to have little relationship to the canyons themselves, being far too small to fill even the floors of these channels. Normal erosion was out of the question, especially given the relatively young age (post-ice age) of the features. A map of the Channeled Scablands seems to indicate that the water entered from one or a few narrow points to the northeast and drained to the southwest. However, the volume of flow is such that it spread out over the Columbia Basin like water quickly poured from a gigantic bucket. The branching channels in this area are described as braided or "anastomosing" channels. Another feature of the Scablands is "hanging" valleys, where the flood cut across existing - and much shallower - stream channels, producing a deep gorge with shallow cuts on each side. These lead to waterfalls (Multnomah is a good example) which emerge high on the side of the larger valley and fall to the floor. (These can also be features of glacial erosion, but here the shape of the deeper channels is wrong for that, as mentioned above.)

The features of Dry Falls are a case in point. This feature is immense. The rim of the falls extends for nearly six and a half kilometers. There are plunge pools the size of small lakes along the base of the falls. Had glacial erosion made this feature, the precipice of falls would have been ground away to form a smooth slope, and there would have been no plunge pools formed by falling water. This leaves liquid, flowing water erosion as the formative agent for Dry Falls, but there is no obvious source for enough water to make such an immense waterfall.

Moreover, given the violence of the activity it was certain that it had not lasted long. Which led to an additional problem. Proposing massive quantities of water flowing through land which the geologic record showed had never had huge amounts of rainfall was one thing. But to form these features would also require this water to flow through in a matter of only weeks, perhaps days. Not hundreds of thousands of years.

In a series of papers beginning in 1923, J. Harlen Bretz proposed - then argued in support of - the hypothesis that the Channeled Scablands and its attributes were caused by a stupendous flood, which he called the "Spokane Flood" (Bretz, 1923b, 1925, 1928a, 1928b, 1928c, 1929, 1930b, 1932). These works sparked a famous and spirted controversy, as well as encouraging other people to finally try and explain the bizarre features. Several rival ideas intended to account for the scablands by means other than giant floods appeared in the 1920s through 1940s. There were also major formal critiques of Bretz' proposal, all of them stating that he had not accounted for the origin of the water or how it flowed so suddenly. However, the concept answered so many questions about the Scablands that many were willing to consider it. Even the ultra-conservative Pleistocene geologist Dr. Alden wrote that the phenomena described above appeared to be river work "if you could only show where all the water came from in so short a time."

Bretz essentially proposed a catastrophe - a flood in which the sudden release of a volume of water much larger than that which now annually flows through the area produced the very large scale erosion. This was the direct antithesis of Uniformitarianism. In many ways his idea was a geological precursor to Punctuated Equilibrium in evolutionary theory. As we might expect, the concept was resisted by most geologists. The Channeled Scablands were instead generally attributed to glacial erosion through much of the Twentieth Century. Bretz kept on with his field work, looking for further evidence which would help settle the matter.

Bretz was not the first proponent of the idea. McMacken (1937) attributed a "Flood Theory" to a teacher at Lewis and Clark High School, Alonzo P. Troth, who apparently never published his work. Details are not known, so how well the teacher's ideas fit the actual features of the Scablands and how close they were to Bretz' can't be evaluated. Additional support came from others. J. T. Pardeemay had been wrong in his 1922 interpretation of Scabland flood bars, but his 1940 description of giant current ripples (the "ripples" mentioned above) proved to be the key point for convincing skeptics of the cataclysmic flood hypothesis.

Still, Bretz was faced with two challenges: 1) Finding a mechanism for producing the huge volumes of water necessary, and 2) Providing evidence that excluded other possible interpretations to the satisfaction of most geologists.

Evidence gathered through the decades strengthened Bretz' case, but left many geologists unconvinced. What was missing was evidence for the large body of water and its sudden drainage. In part this was found in "beaches" on the mountainsides above Missoula, Montana. These lines can be followed for miles and allow outlining a lake which extended over much of western Montana.

Not long after these speculations began to appear, J. T. Pardee wrote Bretz (3 June 1925) inquiring "whether you have considered the possibility of the sudden draining of a glacial lake" to produce the water required for an enormous "Spokane Flood?" Eventually, starting in 1940, Pardee himself began to answer the question he posed to Bretz 15 years earlier. He reported evidence such as giant water-current dunes (there they are again) indicating that there had been a colossal discharge from glacial Lake Missoula; a gigantic flood aimed straight for Bretz's Channeled Scablands. Moreover, remnants of a glacial dam have been located at the east end of Lake Pend Oreille in the Clark Fork River valley. Bretz's final field season in 1952 uncovered new evidence supporting a series of giant floods in the area, including more giant current dunes (Bretz and others, 1956). The resulting report completely vindicated Bretz and his great-flood theory and ended effective opposition. Much later, in the Seventies, hydrological analysis showed that Bretz's extensive qualitative observations were generally consistent with principles of open-channel hydraulics, giving Bretz' once-heretical theory quantitative support.

More support came from studying where all that water could go in a such short time. The Columbia Gorge drained away some of this water and was eroded significantly in the process, but much would have backed up into the Yakima and Snake River valleys. Exploration of these features found that the flood left sandbars as the water slowed and its load of rock and sand settled out. These sandbars are unusual in two respects. First they point upstream relative to the current flow of the river. Second, they are often high on the valley side, suggesting that the water was very high when they were deposited. In most such bars there are many layers, suggesting that many floods, up to as many as seventy.

It is now generally agreed that between 15,000 and 12,800 years ago a series of more than 40 tremendous deluges poured across large parts of the Columbia River drainage. They were the greatest scientifically documented floods known to have occurred in North America. Over 41,000 square kilometers were inundated to depths of hundreds of meters. Swollen by the flood waters, the Columbia grew to contain ten times the flow of all the rivers in the world today. The final concept describes the formation of a dam (probably remnant glacial ice) which would hold back the normal rainfall and snowmelt for many years, and then suddenly break, releasing this water over a period of days or weeks. If a glacier blocked a stream valley, water would rise behind it. If it failed, it would do so catastrophically since ice is brittle and as it began to break up, blocks of ice would float away on the flood. This sequence would provide the large volumes of water needed to explain erosional features such as Dry Falls and explain why these features don't conform to the more common characteristics of stream erosion or glacial erosion. And this damming and collapse would have happened many times, as the ice advanced and retreated. Since the floods appeared to originate in the Spokane area, Bretz termed them the Spokane Floods.

One of the most vocal critics of Bretz' concept to explain the Channeled Scablands was a prominent geologist named James Gilluly. After years of often bitter debate, and growing evidence in favor of the floods, he finally went to see for himself. He took one look at Palouse Falls, threw his arms wide and exclaimed "How could anyone have been so wrong?" Like many of those who disputed Bretz, he had never visited the Channeled Scablands before this, so the obvious disparity between the small stream and the big canyon and plunge pool at Palouse Falls had not hit him. To not only admit he was wrong, but to do so in such a manner showed just how accepting real scientists can be of new ideas, if they can be properly supported.

Bretz was awarded the Penrose Medal (the American Geological Society's highest award) in 1979 at age 96.