Relive Important Archive Articles

A large number of important articles get buried over time as new articles are added to our website, so here’s a chance to review and relive some of our most important articles. We think you might enjoy reviewing these timeless features.

The Great Blade – Bruce Bjornstad Video

“…there were a few double falls each member of which receded at approximately the same rate, so that the island in mid-channel became very much elongated, like a great blade, as the falls receded and the canyons lengthened.” J Harlen Bretz (1928) A tall, narrow basalt ridge, coined “The Great Blade” by J Harlen Bretz, parallels Lower Grand Coulee east of Lake Lenore. The blade is the product of Ice Age floods that repeatedly rampaged Grand Coulee as recently as 15,000 years ago. Most of the floods appear to have come from sudden outbursts from glacial Lake Missoula. During flooding the coulees on either side of the Great Blade were filled with up to 800 ft turbid water. The largest floods also overtopped the Great Blade, submerging the site under at least another 100 ft of floodwater. On the west side of the blade, where Lake Lenore is located, lies the Lower Grand Coulee, which ultimately migrated 10 miles northward – all the way to Dry Falls. On the east side of the blade is the higher East Lenore Coulee, which migrated a shorter distance (~3 mi) to Dry Coulee. Like a gigantic rib the Great Blade is tallest and narrowest at its south end, widening to the north. The blade extends for almost four miles from where the head of East Lenore Coulee intersects Dry Coulee. In places the blade narrows to as little as 800 ft wide. Video produced by Bruce Bjornstad for Ice Age Floodscapes

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DECIPHERING THE CHANNELED SCABLANDS FIELD WORK CONTINUES

In August, Scott David, a postdoctoral researcher and Karin Lehnigk, a 2nd year PhD candidate from the University of Massachusetts visited the scablands for a week to do field studies. Karin was in search of granite erratics. Samples of these were taken to be processed for Beryllium-10 exposure dating, a robust geochemical technique which enables researchers to determine how long the object sampled has been sitting on the surface of the Earth. This information combined with computer simulations of a range of flood sizes is to test the hypothesis that the earliest floods through the Cheney-Palouse Scabland Tract were also the largest. Scott was in search of potholes. Measuring the geometry of potholes and the rocks that comprise them in a variety of locations, he is using these measurements in numerical and physical modeling experiments to explore what erosion mechanisms could generate these massive features. Were they produced by retreating waterfalls, rocks circulating at the base of the flow, large scale turbulence, or some combination of these mechanisms? The results of the study should provide insight into how the remarkable canyons that comprise the Channeled Scablands formed. On a Friday afternoon, I met up with them in Ritzville and proceeded to some granite erratics near Cow Creek southeast of town to take samples. They spent the night at our house in Washtucna and were thrilled to have hot showers, a home-cooked meal and soft beds. The days before they slept in tents on a gravel parking lot. The next morning, Chad Pritchard from EWU joined us as we took measurements from four pot-holes along the south side of Washtucna Coulee between Washtucna and Hooper. They also took granite samples from the Midcanyon Bar near Lyons Ferry before returning to the Grand Coulee area. The results of their studies were not available at time of printing. Article by Lloyd Stoess in The Scablander

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Waning Pleistocene Ice Sheet Affected Megaflood Paths and Local Shorelines

Have you ever thought about the how the weight of the ice-age Cordilleran ice sheet might affect the underlying Earth’s crust. There is strong evidence that the crust was depressed hundreds of feet beneath the ice, and since the crust is relatively thin and rigid over a plastic aesthenosphere, that also caused the crust for some distance beyond the ice margins to tilt toward the ice sheet. A new modeling study explored how changes in topography due to the solid Earth’s response to ice sheet loading and unloading might have influenced successive megaflood routes over the Channeled Scablands between 18 and 15.5 thousand years ago. The modeling found that deformation of Earth’s crust may played an important role in directing the erosion of the Channeled Scabland. Results showed that near 18 thousand year old floods could have traversed and eroded parts of two major Channeled Scabland tracts—Telford-Crab Creek and Cheney-Palouse. However, as the ice-age waned and the ice sheet diminished 15.5 thousand years ago, crustal isostatic rebound may have limited megaflood flow into the Cheney–Palouse tract. This tilt dependent difference in flow between tracts was governed by tilting of the landscape, which also affected the filling and overspill of glacial Lake Columbia directly upstream of the tracts. These results highlight one impact of crustal isostatic adjustment on megaflood routes and landscape evolution. Other studies have shown that relative ice-age sea levels were over 300 feet lower worldwide due to the volume of water locked up in ice sheets. Typical depictions of the shoreface extent are generally based on a 300 ft. depth contour, but there is strong evidence that shorelines were up to 200+ ft. higher than present day in marine areas adjacent to ice sheets, again because the crust was depressed by the weight of the ice sheer. A more accurate representation might show a much narrower shoreface in ice-free areas nearer to the ice sheet margin. However, in the Haida Gwaii Strait at the margin of the ice sheet the lower thickness of the ice sheet meant that local shorelines were as much as 550 feet lower than they are today. This was because the much greater thickness of the center of the ice sheet served to push upwards areas at the edge of the continental shelf in a crustal forebulge. It is now widely thought that these emergent ice-free land areas might have provided a viable coastal migration corridor for early peoples making their way to the Americas from Asia during the Pleistocene.

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Ice Age Floods: A Journey of Awakening – Susan Langsley

Do you ever hear the Led Zepplin song “Kashmir”  in your head when contemplating the Ice Age Floods? “I am a traveler of both time and space. To be where I have been” –Robert Plant, Led Zepplin’s Kashmir My 11-year old daughter and I are on a 5-day, 4-night raft trip on the Lower Salmon river and we are having the time of our lives!   Sun, sand, water, lovely food, games and some of the finest nicest Eastern Oregonians we have ever met. One of the guides is a sensitive and strapping young man who is a student at U of Oregon. He’s both an English major and a Geology major. What do you with that? You write about the soul of the earth, true love and adventure, river stories, deep thoughts that cross scientific paradigms. I see him becoming a teacher someday, maybe a science teacher like his Dad. And he’s a kayaker like me. What is so amazing about the Eastern Oregon guides is their familiarity with, connection to, and love of the river and land. They don’t fight traffic or get on the morning commute treadmill every day. There are no stoplights in the whole of Wallowa County, and the only food franchise is a Subway sandwich shop, no Costco or Walmart. Sure, they have school and work, but they are connected to and love the land they live on in deeper ways that us city folks miss. They are here to tell us about the land. They are guides. The 4th day on the river we pass a group of pillar-like rocks with beautiful symmetry.  “That’s columnar basalt” my guide says, “The geologist who figured out the floods and travelled around these parts was J Harlan Bretz”.  “J Harlan Bretz” I repeat, carefully, committing to memory. When I returned home to talk to my friend (who was a geology major at Wesleyan) about the trip, she replies “’J Harlan Bretz,’ Oh yes, I have all his books!” An Amazon search and I begin by reading a biography of J Harlan Bretz, “Bretz’s Flood” by John Soennichsen- (some guy from Eastern Washington… hmmm). And guess what: It’s so well-written, I can’t put it down!  I am enthralled cover-to-cover with the character of J Harlan Bretz, his teaching method of taking students to the field (and floating them downstream on large Sequoia logs, upon occasion), his love of life, the serendipity of his study of the USGS Quincy Basin topo map when it first published, many summers spent driving around and measuring the Channeled Scablands,  presenting his field evidence and theories at the Cosmos Club in Washington DC, and most of all his ability to KNOW he was RIGHT when all his colleagues scoffed and dismissed his theories.  Now THAT man was a pillar of strength. Perhaps like a column of basalt? If he were alive today, Harlan Bretz could stand up to money-motivated physicians – the bad kind, nepotism in the school district, gossipers and bullies, and other types of corruption, all of which I have had to do to defend my younger child against since. J Harlan Bretz helped me to do this. He was a GREAT man! “All I see turns to brown.. And fills my eyes with sand as I try not see the wasted land” – Kashmir by Led Zepplin What was it about those floods, biblical in nature, that left behind a story of such jaw-dropping inspiration? Who are these people who live in Eastern Oregon and Washington and are so inspired by the landscapes there they are called to find new ways to study it, publish, write fantastic biographies? I continued my search to find other scholars of the Ice Age Floods, and that led me next to Nick Zentner and Bruce Bjornstadt. To be continued…

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Front Porch: Water etches interesting stories on landscape

I have always loved the ocean. I spent my growing-up years in, on or at least somewhere near the Atlantic Ocean and its various bays. The feel of ocean water, its movement, how it smells and all the amazing life that it supports – wonderful. And whenever I looked over the ocean’s horizon, it wasn’t scary, but rather full of potential for what was just beyond what I could see. When I moved to Spokane – clearly, no ocean, but lots and lots of freshwater lakes and rivers. I have spent I can’t tell you how many of my adulthood hours, swimming in Lake Coeur d’Alene, Lake Pend Oreille, Priest Lake, etc. And sailing. And walking along riverbanks. And tossing sticks into whatever body of water, fast moving or still, that was before me, for our dog to fetch. Water is wonderful. As a young bride, newly relocated to Eastern Washington, lo those many years ago, I took my first drive to Seattle with my husband. Heading up the Sunset Hill, passing Four Lakes, then Fishtrap, then … yikes. Where did the water go? There was a long stretch – broken up briefly by Sprague Lake and Moses Lake – of what was the thirstiest landscape I’d encountered. It wasn’t until we crossed the Columbia River and drove up and past the Vantage Grade did I begin to see deciduous trees and bigger leafy plants that suggested the rainfall amounts required to support them. It got lush and humid and wet as we drove west. We were heading to … water! I just endured that unappealing stretch of land between Fishtrap and the Columbia over a number of years driving back and forth to Seattle. Not only was it dry, it was essentially treeless. One friend of like mind said it was best just to drive through there at night because the view would be just as interesting. So much for being young and stupid. It was still kind of dry for my taste, but I began to appreciate how the sunlight hit the terrain at different times of year and in different weather conditions. It still wasn’t water, of course, but it kind of grew on me. It’s hard to live in this neck of the woods and not learn about the wonderful Columbia Basin Project that brought irrigation to east-central Washington (ah, water!), which produces amazing amounts of agricultural products for export and to feed us all. But what really sold me on that, to me, foreign scenery was back when I worked at Eastern Washington University and I met the terrific Bob Quinn, professor of geography, who loved the environs of the state’s east side with a zeal and passion I couldn’t possibly imagine. He gave me some information, and I began to read about this landscape I’d so easily dismissed – land that was scoured by massive floods some 18,000 to 13,000 years ago (the last Ice Age), floods from glacial Lake Missoula that carved out the canyons and created braided waterways now known as the Channeled Scablands of Eastern Washington. The floods were cataclysmic, with estimates indicating that 500 cubic miles of water that was 2,000 feet deep, burst forth at 386 million cubic feet per second – all headed this way, and beyond, in one darn big rushing, gushing explosion. And then it built up and did it over and over again. That’s a lot of water. I began looking at the landscape differently as I drove through, marveling at the magnificence of that creation, and saw that it has its own beauty – not to mention a heck of a back story. How ignorant of me to just have ignored all that geologic magnificence because it didn’t fit into my preferred norm. I thought about that again on our most recent drive to Seattle to visit our son. Clearly, I am no longer a young adult full of not-burdened-by-knowledge opinion and attitude, but an older person with a fair number of miles on her and, I hope, a greater realization that everything deserves a second look – and also, that a little research is also a good thing. Because I read a book and some supporting literature, I discovered things that gave me a different set of eyes with which to see a particular section of the world around me. I’m trying still, even in my old age, to keep doing that. Never too old to read a book and learn something. Or to change a mind. The Spokesman Voices correspondent Stefanie Pettit can be reached by email at upwindsailor@comcast.net

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First Peoples Ice-Free Corridor Migration to Americas Reexamined

Analysis of how long erratics have been exposed on ice-free ground in the hypothesized “Late Pleistocene ice-free corridor migration route” suggests that route was not fully open until about 13,800 years ago, and the ice sheets “may have been 1,500 to 3,000 feet (455 to 910 m) high in the area where they covered the ice-free corridor,” according to study lead author Jorie Clark, a geologist and archaeologist at Oregon State University. Clark said, “we now have robust evidence that the ice-free corridor was not open and available for the [Late Pleistocene] first peopling of the Americas.” If evidence of humans in the Americas prior to the 30,000 years ago is ultimately found, that evidence does not preclude the possibility of ice-free corridor migration before closure of the corridor. 

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Glacial Lake Missoula – A Portrait

In this video Tom Davis flies you back some 13,000 years ago to see and hear what the landscape of Glacial Lake Missoula might have looked and sounded like. A virtual recreation of the magical ice-age lake and its catastrophic floods. Produced by Tom Davis, GLM Wine Company, Blaine, WA minutes) 

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Hydraulic Modeling of a Missoula Flood

Chris Goodell’s 1-hour video presentation of his Ice Age Flood hydraulic modeling is both enlightening and thought provoking. Chris is a hydraulic modeling professional for Kleinschmidt Group, whose personal interest in the Ice Age Floods phenomenon led him to privately undertake HEC-RAS modeling of a possible Ice Age Flood hydraulic response. His presentation for American Society of Civil Engineers – Environmental & Water Resources Institute – Seattle (ASCE EWRI Seattle) provides interesting insights to the Floods Story even as it recognizes many of the obstacles and shortcomings of what we can know about details of any Ice Age Floods. 

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