The Blind Men and the Elephant, as Told by Geologists: The Channeled Scablands of Washington

A dry channel in basalt on the Columbia Plateau in central Washington (photo by Mrs. Geotripper)

I'm sure most are familiar with the parable of the blind men and the elephant. Several men investigate an elephant, but each touches a different part, so one describes it as being like a snake (the trunk), and others as a wall (the body), a rope (the tail), a fan (the ear), or a tree (the leg). The story of the Spokane Floods and Channeled Scablands of Washington is pretty much the Blind Men and the Elephant as told by a Geologist. In this retelling, the geologist is just as blind as the others, but hearing the arguments among the others, decides to investigate further. He goes back, touches the trunk, the body, the tail, the leg, and ear, mulls on it for awhile, goes back to the arguing men and says "You aren't gonna believe this guys...".

Channeled Scablands and Palouse Soils near Davenport, Washington (photo by Mrs. Geotripper)

J Harlan Bretz was a Seattle-area high school science teacher in the early 1900s, and after receiving his doctorate in 1913 he became a professor at the University of Washington and later at the University of Chicago. He was interested in glacial features of the Puget Sound, but eventually started to explore the strange landscapes of the Columbia Plateau east of the Cascades. The plateau was volcanic (horizontal basalt flows), but it was covered by a fertile silty sediment called the Palouse Soil. The soils have been used for growing vast amounts of wheat over the years.

But the soils weren't everywhere. In many places they had been stripped away, leaving barren rugged channels across the prairie. Most of the channels could not be directly related to modern rivers, but geologists used the Pleistocene ice ages as an explanation. The vast ice sheets covered and changed the landscape, and river drainages would have been altered. The outwash from the melting glaciers could account for the apparently high volumes of river flow required to form the channels.

But to Bretz, these facts weren't adding up. As topographic maps were finally becoming available for the region, he was starting to see the bigger picture of where these channels were found. He was, as it were, becoming a bit less blind. A startling hypothesis was beginning to form in his mind, an idea that would eventually transform our perception of one of the central underlying assumptions of geology.

Geology made a giant leap forward in the early 1800s when James Hutton first articulated the principle of uniformitarianism, the idea that we can use our understanding of present-day processes to interpret what has happened on the Earth in the past. The idea that things happened according to the laws of nature in the past as they do today was a powerful model for understanding how rocks and structures came to be. As the science developed over the next century, the principle hardened into a sort of orthodoxy that all geological processes were constant, and generally slow. This was in part a response to the idea of catastrophism, a model that suggested that some geologic phenomena could be explained by unusual and violent events. To many geologists this smacked of religious explanations like global floods.

Boulder field near Moses Lake (photo by Mrs. Geotripper)

The more Bretz explored the region, the more he was convinced that something extraordinary had happened here. He documented the braided pattern of the dry watercourses, eventually referring to the rugged landscape as the "Channeled Scablands". He discovered gigantic ripplemarks in some of the channels. His research led him to suggest that a series of huge floods had affected the region, floods without precedent in the modern day. His hypothesis seemed to run counter to the principle of uniformitarianism and his proposal met with fierce opposition in the geological community.

Among the weaknesses of his proposal was the source. Where had so much water (an estimated 500 cubic miles) come from? Bretz didn't have a good answer. At first.

Gigantic ripplemarks on the Camas Prairie of Montana

There were really two "blind" geologists looking at the Scablands problem. At the same time that Bretz was working on the Columbia Plateau, J.T. Pardee of the U.S. Geologic Survey was documenting evidence for a huge ice age lake that flooded canyons and plains in western Montana. It is said that he leaned over during a conference in the 1920s where geologists were eviscerating Bretz's hypothesis, and told his colleague "I know where the water came from". It was a number of years before the two put their ideas together as a comprehensive model, and it took even longer before the hypothesis gained widespread acceptance in the geological community. 

Our understanding of uniformitarianism had to change first. There was actually no logical reason to insist that geological rates were constant, slow, and unchanging. The current understanding of the principle is that the natural laws that govern any phenomena are the constant. If it looked like a river had transported boulders, then if channels existed with much larger boulders, then a much larger river was required, even if no such river exists in the present day. If a "small" crater like Meteor Crater in Arizona was produced by a fifty-foot wide meteorite, then a 130 mile wide crater like the one in the Gulf of Mexico would be produced by a much larger rock, maybe ten miles wide. Such a collision with the Earth would surely be catastrophic, and the available evidence suggests strongly that this one destroyed the dinosaurs and many other species on the planet. Catastrophism can be an acceptable explanation if it doesn't disobey the laws of physics and chemistry.

Bretz and Pardee had put together an amazing geological story: during the ice ages about 15,000 years ago, a massive glacier had blocked river drainages in Montana, producing a lake of 3,000 square miles and 500 cubic miles. In places it would have been 2,000 feet deep. On a number of occasions the dam had collapsed and the water rushed out in a catastrophic flood with a flow ten times that of the Amazon River. The floodwaters rushed across the Palouse prairie, carving the Channeled Scablands during the headlong rush to the sea. No modern historical flood comes close

Ripplemarks on the Camas Prairie in western Montana

We were on the last stages of our exploration of Canada and the Pacific Northwest, making our way back to Seattle via the Camas Prairie in western Montana and across the Channeled Scablands in central Washington. Our first stop found us on the Camas Prairie at Markle Pass.

The Camas Prairie was one of the spots where J.T. Pardee was able to document the existence of glacial Lake Missoula. Not only were there shoreline terraces carved into hillsides (below), but ripplemarks covered the valley floor. These were no normal ripples. They were as much as 30 feet high with wavelengths of 200-300 feet. The hydraulics suggest that the lake was draining fast enough to produce currents of 45 mph on the valley floor.

Ripplemarks and wavecut shorelines on the Camas Prairie in Montana

We left the Camas Prairie and drove west through canyons that had once contained a lake 2,000 feet deep. At Coeur d'Alene and Spokane we broke out into the plains of the Columbia Plateau, and our route passed through hills of Palouse Soil interspersed with jagged channels of basalt. In the afternoon we arrived at one of the most astounding results of the flood, the Dry Falls at Sun Lakes-Dry Falls State Park.

Dry Falls State Park in Washington

The park preserves a 400 foot deep valley that was carved in a matter of days by the flood that was probably 300 feet deep at this point. The waterfall was 3.5 miles wide. It is one of the most astounding pieces of evidence for the gigantic floods. I can only imagine what the scene would have been like on one of those days 15,000 years ago. A day like any other except for the rising fog in the distance and the dull roar of the coming waters.  What a sight it would have been.

Dry Falls State Park in Washington

In the early years of his research, Bretz did not have the benefit of maps or aerial photographs. Today hundreds of thousands of airline passengers pass over the Scablands yearly, often without looking out the plane window. It's quite a sight when you realize what you are seeing. I took a couple of shots a few years ago.The Palouse Soils show clearly in the upper part of the photo, while the dark basalts of the Scablands dominate the lower part. Note the small village on the lower right for a sense of scale.

Even the view from a plane fails to communicate the full size of the flood. Satellite images are the only ones that can reveal the true scale of one of the world's great catastrophic events.

Palouse Soils and Scablands Channel in central Washington

One can say that the flood seems obvious when seeing the satellite view, but Bretz and Pardee had only the ground perspective to work with, and their years of detailed research and careful documentation. They were the blind men touching the different parts of the giant elephant, but they had the insight and evidence to put the whole story together. Decades passed before their model was accepted by the geological community, but they did receive recognition in the end, and the science benefited from a new perspective on the principle of uniformitarianism. It is one of the great stories of geology.

Source: http://www.cr.nps.gov/history/online_books/geology/publications/inf/72-2/sec5.htm

We pulled into our motel at Moses Lake for the final night of our Northern Convergence tour of Canada and the Pacific Northwest. We still had some incredible sights ahead on our last day on the road.

A Convergence of Wonders: A Compilation

The trip I called the Convergence of Wonders was a combined geology and archaeology course that we conducted on June 15-30, 2011, in which we explored the Pacific Northwest and Northern Rocky Mountains. Our students and volunteers traveled more than 4,500 miles through regions that have been influenced by convergence along the Cascadia and related subduction zones, as well as a hot spot and continental divergence. Each day revealed stunning geological features and insights into the human occupation of the region over the last 13,000 years or more. This is a compilation of all of the blog entries I posted about the trip.



"Journeys in the Pacific Northwest" was the introductory post about the series, and provided some background about why we did the trip we did, and what our goals were. 





"Journeys in the Pacific Northwest, Day 1" was the story of the trip from home to our first camp at Lava Beds National Monument on the night of the full moon. En route, we explored the flanks of Mt. Shasta, the largest stratovolcano in the Cascades, and found out that a record snowpack and late spring was going to be a problem on this trip.

"Day 2, Lava Beds and Newberry Caldera" includes our exploration of Lava Beds National Monument, including the extensive lava tube system, an incredible panel of petroglyphs, and the site of the last war between the federal government and Native Americans in California. Late in the day, we visited an obsidian dome in Newberry caldera.

"Day 3, Crossing the Subduction Zone" chronicled our passage across the Cascades to the Washington coast at the mouth of the Columbia River at Cape Disappointment State Park. Smith Rock State Park in Oregon was an incredibly scenic view into the heart of a rhyolite caldera eruption, and our day ended looking pillow basalts from the floor of the Pacific Ocean floor. In between, we checked out an excavation taking place at Fort Vancouver.

"Day 4: Cape Disappointment and Real Disappointments" was the story of weather-related disappointments. The skies opened up throughout the day, including along the flanks of Mt. St. Helens, which was to be the centerpiece of our exploration. The mountain remained invisible in the clouds. The sun emerged, of course, but not until we were far beyond the crest of the Cascades and almost to our camp in Yakima.

"Day 5: In the Land of the Great Flood" was a narrative of our passage across the wastelands produced by a series of catastrophic floods that defy human imagination. At Dry Falls, we looked at canyons (the coulees) that were carved in a few days or weeks of remarkable "river" flows hundreds of feet deep. We also had a chance to see the Wenas Creek Mammoth at Central Washington University.

"Day 6: In the Land of the Great Draining" was an exploration of the lands where the floodwaters originated: glacial Lake Missoula. We traversed a barren valley (the Camas Prairie) where ripplemarks thirty feet high convinced many geologists of the occurrence of the Spokane Floods. We arrived in beautiful Glacier National Park at the end of the day, and were greeted with an incredible rainbow.

"Day 7: Of Time and Pressure in Glacier National Park" found us at the Canadian border where we started an exploration of Glacier National Park, at least the parts that were not still snowbound. We checked out the Lewis Overthrust, and examined the Proterozoic sedimentary rocks that make up much of the park.

"Day 8: Of Time, Pressure, and the Plain Truth" found us out on the Great Plains east of Glacier. We toured the Museum of the Plains Indians in Browning, and worked our way past numerous thrust sheets in Sun Canyon, where convergence pushed numerous fault slices over one another. We also checked out some exhibits on some of the most famous discoveries concerning dinosaurs at Choteau, Montana.

"Day 9: Into the Depths of the Crust, and of Time" discusses one of the most spectacular roads in America, the Beartooth Highway from Red Lodge to Yellowstone National Park. We also checked out the Stillwater Mine, where platinum and other rare minerals are produced. The outcrops we were traversing including some of the most ancient rocks on the continent.

"Day 10: Explorations of a Real Hot Spot" was just that...a tour of Yellowstone National Park, one of the crown jewels of the National Park System. We explored Yellowstone Falls, the Grand Canyon of the Yellowstone, Mammoth Hot Springs, and Norris Geyser Basin. The highlight for many of us was the witnessing of a wolf competing with a raven at a kill site.

"Day 11: The Orange Steam is OK, but the Blue Stuff Will Kill You" was a further exploration of Yellowstone, with visits to Grand Prismatic Hot Spring, and the famous geysers in Upper Basin (yeah, Old Faithful was spouting off, but I was watching Beehive). We ended the day in Grand Teton National Park.

"Day 12: A Richness of Geological Drama at Grand Teton (and Pelicans)" was a beautiful day of exploration in the Grand Tetons. We also checked out the Gros Ventre Slide, one of the most famous slope failures in the United States.

"Day 13: Hidden Treasures and Hazards on the Road in Western Wyoming" saw us beginning the long journey home. We checked out the Game Creek Archaeological Site and Fossil Butte National Monument, and saw a lot of sagebrush as we made our way south into Utah...

"Day 14: Treasures Discovered and Lost in Nine Mile Canyon" chronicles an expedition through seventy-mile long Nine Mile Canyon, a showcase of Fremont Culture artwork and archaeological sites. The canyon is also a site of controversy, as heavy industry is mining natural gas in the area, with profound effects in the canyon itself. Later in the day, we saw the Dinosaur Museum in Price, and ended the day searching for Topaz crystals in the western Utah desert.

"Day 15: We Go Underground in Great Basin" saw us making a 500 mile journey across the Basin and Range Province, with a stop at Great Basin National Park for a tour of Lehman Cave, and a stop at Garnet Hill, for, eh, garnets. A motorcycle accident caused us to arrive in a spooky camp at 11:00 PM.

"Day 16: Our Home Mountains, Giant Swimming Reptiles, and a Bunny" was our last day on the road. We checked out the bizarre Mesozoic creatures at Berlin-Ichthyosaur State Park in Nevada, Mono Lake in eastern California, and Yosemite National Park in our backyard before arriving at the end our journey.

A Convergence of Wonders: Day 5, In the Land of the Great Flood

In the movie "A River Runs Through It", the narrator ends with the following, one of my favorite quotes in any movie...

Then in the Arctic half-light of the canyon, all existence fades to a being with my soul and memories and the sounds of the Big Blackfoot River and a four-count rhythm and the hope that a fish will rise. Eventually, all things merge into one, and a river runs through it. The river was cut by the world's great flood and runs over rocks from the basement of time. On some of those rocks are timeless raindrops. Under the rocks are the words, and some of the words are theirs. I am haunted by waters.

Because Norman Maclean's father was a Presbyterian minister in the 1920s, and his preaching and teaching was one of the ongoing themes in the book and movie, I assumed the referred-to flood was Noah's, but when I picked up the book, I was surprised to find that he was actually speaking about the Spokane Floods. My appreciation and respect for Norman Maclean jumped up many notches.

Geology, a science that embraces change more than any other, was caught in a form of stasis at the beginning of the 1900s. Geologists embraced the principle of uniformitarianism, the idea that we can learn of past processes by looking at those that are active today. It is in fact the founding principle of the science, but a hundred years after adopting it, geologists were trapped into a mental construction that required that all processes were the same, and that they operated at the same rate as they do today.

J Harlan Bretz was a high school science teacher in Washington state (later a professor in Chicago). He was mystified by elements of the landscape across the drainage of the Columbia River, especially a region that he called the Channeled Scablands. Numerous dry river channels and small depressions cross the high plateaus of basalt, carving up the windblown silt prairies into islands of fertile soils (the Palouse Soils). I posted an aerial photo of some of these silt islands here.  In places, the dry channels were in deep canyons separated by long-dry waterfalls (the Coulees).

Bretz wanted  to know how this landscape...

...became this one...

Conventional geology explained the dry river channels as having formed as a result of erosion by rivers draining off the melting glaciers of the last ice age, since the vast continent-size glaciers had terminated only a short distance north and east of the region. But the river hypothesis couldn't explain the ponds among other things; rivers don't normally form isolated lakes, except in cutoff oxbows. Bretz began to study the strange landscape, operating without the benefit of aerial or satellite photography. He developed a startling hypothesis: the channels and scablands had formed during a giant flood or series of floods of short duration.

When he published papers on the subject in the 1920s, geologists were aghast. Giant floods covering the landscape to a depth of hundreds of feet were not a part of normal geologic thinking. It smacked more of religious catastrophism. And Bretz couldn't say where the floods had come from. But the evidence accumulated, and after only a few decades, geologists came to accept the model. Luckily, Bretz lived long enough to see his ideas accepted, and he was ultimately given geology's highest from of recognition, the Penrose Medal (geologists don't get Nobels). Other geologists even found the source of the flood, a gigantic lake in Montana (Lake Missoula) that formed as the tongue of a glacier blocked a river drainage. The floods occurred when the unstable dam collapsed, unleashing cubic miles of water across the Washington landscape.
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That's where we were headed on the fifth day of our journey in the Pacific Northwest.

The rains of the previous day were gone and forgotten. The day was bright and clear as we headed north out of Yakima. Our first stop was Central Washington University in Ellensburg where we talked with the archaeologists who have been studying dating of human teeth, and who have been excavating the Wenas Creek Mammoth Site. Pat Lubinski took us on a tour of the lab where the fossil specimens have been laid out (the giant femur in Dr. Lubinski's arms is a lightweight cast, in case you were wondering).

In case you wonder about how we keep our army of students moving and fed, here is a shot of our shopping trip at the big grocery store in Ellensburg. There was a Starbucks, so the students were content.

At Vantage, we had a chance to see some pillow basalts and palagonite clay that formed when some of the plateau basalts flowed into a lake or swamp around 15-16 million years ago. The quartz-rich sands at our feet were deposited by swirling eddies during the Spokane Floods. Quartz is rarely seen in basalt; it was carried to the area from elsewhere.

Vantage also provided us a nice cross-section of the basalts that underlie the Columbia Plateau. The vast outpouring of lava covered tens of thousands of square miles of eastern Washington, Oregon, and northeastern California. Some of the flows traveled several hundred miles from vents near Spokane all the way to the Pacific Coast.

 At Lenore Lakes there were cliffs and deep valleys, but no river, just groundwater-fed lakes.

There were also some beautiful flowers! Does anyone want to identify it for me? It reminded me a bit of our Mariposa Lilies back in the Sierra Nevada.

We were in one of the coulees, the rapidly eroded canyons that formed in the Spokane floods. Eddies in the flood scoured out the columns, but not the overlying entablature rocks, forming deep alcoves. The alcoves have been used for thousands of years by humans as temporary shelters. In the 1930s, a hollow in the cliff nearby proved to be the mold of a rhino-like mammal that had died and then was covered by flowing lavas.

Dry Falls State Park is one of the most spectacular monuments to the vast floods that crossed Washington on the headlong rush to the sea. There was a 300 foot high waterfall here, miles across, which would have been nearly invisible in the deep waters (the photo at the beginning of the post is the main view of the falls). The scale of the event is nearly unimaginable.

Just upstream is the Grand Coulee, an even deeper channel cut by the floodwaters. Dam(n) engineers realized the potential for water storage, and constructed Banks Lake to fill it. The road is spectacular.

We made a brief stop at Grand Coulee Dam ("Roll on, Columbia roll on" - did anyone else sing the Woody Guthrie song in grade school?). I seem to recall reading that this is the biggest chunk of concrete anywhere in the world. I haven't fact-checked this claim.

Then it was a run across the scablands and the Palouse prairie to Spokane and our camp at Bowl and Pitcher State Park along the nearly flooding Spokane River. It was a very nice grassy campsite, and a comfortable night. Tomorrow we would be seeking the source of the floods in Montana. And the glaciers of Glacier National Park.