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.

WA Geology Releases Stunning Lidar Images

The Washington Geological Survey (WGS) has released 50 high-resolution lidar-derived images of the State’s geology and geomorphology through the Washington State DNR’s Flickr page. The images are available in 16:9 format (7,200 x 4,050 pixels) and 4:3 format (7,200 x 5,400 pixels). Ten of the images are new (see below) and 40 of them were previously available as screen wallpaper (at a lower resolution). Additionally, WGS has released several full-resolution lidar image series that reveal the State’s geology. These images are great for earth science presentations, learning about lidar, and for using as digital wallpaper. They are also large enough to support large-format printing. Here are direct links to the image galleries:  

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My Hill

As a city kid in the ‘60s my family occasionally visited my grandparents in the farm country of Washington State’s Waterville plateau. My grandfather and two uncles were wheat farmers near the small town of Withrow, the future site of which had been partly hedged in by the Okanagan lobe of the Cordilleran Ice Sheet many thousands of years ago. Sometimes my father and I would join my uncles on the dusty 15-minute drive “out in the hills” to the sagebrush-surrounded corral, well house and large cement watering trough that served the cattle herd pastured there. Overlooking the corral was a tall hill I would sometimes climb while the trough was refilling. Warned to beware of rattlesnakes, a tiring five- or ten-minute ascent would get me to the top. Astride a large boulder, I would survey the corral far below, the sound of the pump engine distantly laboring. Around me was a panorama of other hills, about whose origins it had never occurred to me to wonder. “My hill” was steep enough that even oblong rocks I tossed down its flank would often bounce and roll clear to the bottom. On occasion, this would elicit salty, muffled hollering from Dad to cease and desist. I’m a half-century older, now, but I wish I had then understood the remarkable history of my hill. How would it have felt at that young age to know that a vast ice sheet had blanketed this terrain some 12,000 years earlier and that the hill I stood on had been its progeny? That, as that glacier began to melt, streams and rivulets had formed on its immense surface? That small sinkholes and other weaknesses in the rotting ice had allowed those waters to sculpt caverns inside the glacier? That those waters carried copious quantities of sediment and rock debris captured as the glacier eroded its way hundreds of miles southward? That my hill, like an embryo within an icy womb, had begun to grow inside one of those expanding interior caverns, ultimately to be deposited on solid ground as a kame, a lasting testament to the retreating glacier? Would I have deduced that the glacier had been at least as thick upon the land as my kame was high above the corral below me? That the erratic boulder on which I sat had been deposited on that kame like a cherry atop a geological sundae? I formed an early affection for the Withrow country because of the many relatives who, not so long ago, had peopled that farmland. It’s strange to contemplate that they are mostly gone from this land now, making it seem somewhat alien to me for their absence. And yet that hill remains, a mute sentinel having witnessed the glacier that birthed it, the quiet passage of the millennia, grandpa’s construction of that watering trough in 1948, and the naive delight of a young city kid climbing its flanks in the 1960s. Dan Jordan – IAFI Wenatchee Erratics Chapter

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Glacial Lake Missoula – Inspired Classroom Videos

The Glacial Lake Missoula chapter has worked with Inspired Classroom LLC to produce a series of 9 short (3-7 minute) videos exploring different aspects of the Ice Age Floods in the Glacial Lake Missoula area. The entire set is posted to the Inspired Classroom LLC YouTube channel, including a full 31 minute version (below) that compiles the entire set. 

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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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23,000 Year Old Human Footprints Found in New Mexico

Articles in Science Alert and the New York Times report on a well documented age for many sets of human footprints as old as 23,000 years in the ancient lake shore sands of White Sands, New Mexico. “The footprints were first discovered in 2009 by David Bustos, the park’s resource program manager. Over the years, he has brought in an international team of scientists to help make sense of the finds. Together, they have found thousands of human footprints across 80,000 acres of the park. One path was made by someone walking in a straight line for a mile and a half. Another shows a mother setting her baby down on the ground. Other tracks were made by children.” Beginning in 2019, two United States Geological Survey (USGS) research scientists, Dr. Jeffrey Pigati and Kathleen Springer, began working on the site and found ancient seeds of ditch grass associated with various sets of footprints. The oldest footprints so far have been found in seed beds radiocarbon age-dated as old as 22,800 years, and the youngest footprints dated to about 21,130 years ago. Some scientists still have concerns the seeds might have absorbed older carbon from the lake waters. But in general this research is strongly indicative that humans were present in the Americas long before the generally accepted 15,600-year-old footprint found in Chile or the 13,000 year age of human tools found near Clovis, NM. If humans were well established in New Mexico 23,000 years ago, they must have started spreading down from Alaska long before that. “That starts to wind back the clock,” said Dr. Reynolds of Bournemouth University. Some researchers feel the migration might have been along the coast during the last major ice advance of the Pleistocene, while others argue people could have traveled inland more than 32,000 years ago, before Ice Age glaciers reached their maximum extent and blocked off that route. Regardless of the possible migration route, this new evidence opens up new possibilities that humans may have been present in our local area even before the earliest of the Ice Age Floods, about 18,000 years ago. While the floods could have wiped away most traces of early people in the area, the window of human habitation may be much greater than scientifically documented to date.  

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Let Your Feet, and Your Imagination Roam at Rowena Crest and Tom McCall Preserve

Scenic Rowena Crest and the Tom McCall Preserve area provide an incredibly scenic place to let your feet, and your imagination wander as you look out on a major chokepoint along the Ice Age Floods path. The wildflower displays are amazing during the Spring, but several compelling flood-related features are visible from the vantage of the Rowena Crest Viewpoint any time of year. Rowena Crest lies nearly 700 feet above the Columbia River at the upstream end of the Rowena Plateau, a miles-long plateau that the river flows along. Just upriver from the plateau is the narrow section of the Gorge known as the Rowena Gap The drive to the viewpoint on old Hwy 30 from either east or west is a spectacular ride through a wonderous section of the Columbia River Gorge. A roundabout parking area at the viewpoint, with a safety wall above a sheer cliff, provides a great observation point eastward toward Rowena Gap. At Rowena Crest it’s easy to imagine what it might have been like to witness the approach of those massive floods. There is not yet scientific evidence that humans were in the area to bear witness to the Ice Age Floods, but there is solid evidence of humans in the Americas by that time. And there is growing concensus that if they came in during a glacial maximum, they would have come in by a coastal route that offered plentiful food and shelter for their journey. The mouth of the Columbia River would have been the first major waterway path inland that might have led them to settle in the area of the Floods. Your village might have been situated across the Columbia at the mouth of the Klickitat River where the town of Lyle now sits. If you were foraging, or just relaxing, atop Rowena Crest on a late summer day, you might have felt the ground begin to temble as if there were a small earthquake, but the trembling would have slowly increased for a few hours. Eventually you would have heard a low roaring sound that also grew over an hour or more before you could see turbulent brown muddy water begin flooding across the broad basin to the east. Then the roaring flood of water, only a few feet deep at first, would have entered the narrows, now called Rowena Gap, and sped on, crashing against the promontory you’re standing on and being diverted toward your village which was quickly washed away by the muddy torrent. But the muddy flood waters would have kept rising, unlike the Spring floods you’re used to on the Columbia, becoming a hundred feet deep, then two hundred as the levels just kept rising. Soon a huge whirlpool formed in the flood waters near the base of the promontory and a giant eddy formed where your village had been as flood waters flowed backward up the Klickitat River even as the bulk of the water continued downstream on the main stem of the Columbia. As the flood waters reached 400 and 500 feet deep and kept coming, suddenly to your right and left, huge blocks of the promontory broke off and slumped down into the rampaging flood waters. Now, even more fearful, you would have begun running south toward higher ground, climbing higher and higher as the still rising flood waters poured across the plateau and plunged into the small creek valley to the west, tearing away at the valley walls and massively widening that little valley. Eventually the flood waters stopped chasing you upward as you climbed higher, 200 then 300 feet above the now submerged promontory. Now, as you turned and looked out across that expanse of muddy water you could see massive white blocks of ice being carried along on the flood waters, similar but inconceivably larger than the ice blocks carried on the river during the Spring floods.  But the flood waters didn’t begin to recede that day, nor the next, as they might in the Spring floods. In fact it was almost half a lunar cycle before they began to slowly recede, exposing a mud coated Columbia River valley that was now noticeably wider, with layers of shear vertical rock walls extending over 1000 feet above the normal river level below. As you began the recovery from the floods devastation, your family returned from from their hunting and gathering in the high mountain meadows, and you have an incredible story to pass along to them and your ancestors. This story is easy to imagine as you look out to the east from Rowena Crest. The onrushing Ice Age Floods waters easily flowed over the low relief of the broad Dalles Basin to the east, but the major Rowena Gap created a chokepoint in the path of the floods as they made their way through the Columbia River Gorge. This “hydraulic dam” forced the flood waters to build to over 1000 feet deep in this area, flowing hundreds of feet deep over Rowena Crest while forming a temporary lake in The Dalles basin. It is estimated that many of the 40-100 Ice Age Floods may have taken up to a month to completely flush through the system to the Pacific Ocean, but the duration of the flood waters at any point along the path probably lasted less than a couple of weeks. But this was more than enough to create several major floods features visible from this vantage point. At Columbia River level below and east of the promontory is a round Kolk pond that was created by giant whirlpools in the flood waters as they were deflected around the Rowena Crest promontory. Other similar Kolk features can also be seen on the Dallesport area to the east, and along the hiking path atop Rowena Crest where they are marked by surrounding groves of oak trees. Across the Columbia, the floods deposited a huge eddy gravel bar that the entire town of Lyle, Washington is built upon. The Klickitat River was backed

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Indigenous Flood Stories from 14,000 Years Ago

On October 7th at Chief Timothy Park near Clarkston, WA at the latest Confluence Story Gathering,  Thomas Morning Owl (Umatilla tribe) noted there are indigenous people’s stories of massive floods going back to 14,000 years ago. While he didn’t elaborate, it would be very interesting to have these stories shared as first-hand accounts of the Ice Age and/or Bonneville Floods. Confluence Story Gatherings are designed to elevate native voices in our understanding of the Columbia River system. This Confluence Story Gathering explored stories and perspectives from Nez Perce homelands, where a panel of indigenous thinkers and storytellers — Allen Pinkham, Sr. (Nez Perce), Thomas Morning Owl (Umatilla) and Jefferson Greene (Warm Springs) — shared their observations. Despite the strong winds, rain and even hail, the stories prevailed. Confluence Project is a community supported nonprofit that connects people to place through art and education. We work in collaboration with Northwest communities, tribes and celebrated artist Maya Lin to create reflective moments that can shape the future of the Columbia River system. We share stories of this river through six public art installations, educational programs, community engagement and a rich digital experience. The six projects span 438 miles from the mouth of the Columbia River to the gateway to Hell’s Canyon, with sites in both Oregon and Washington. These are “teachable places,” transformed and reimagined to explore the confluence of history, culture and ecology in our region. Each work references a passage from the Lewis and Clark journals as a snapshot in time, while comparing it with the deeper story.

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Earth Appears to Have a 27.5-Million-Year ‘Heartbeat’

Geologists have been investigating a potential cycle in geological events for a long time. A recent analysis on the ages of 89 well-understood geological events from the past 260 million years show a catastrophic 27.5 million year pulse in eight clusters of world-changing geologic events over geologically small timespans. This pulse of clustered geological events – including volcanic activity, mass extinctions, plate reorganizations, and sea level rises – is incredibly slow, a 27.5-million-year cycle of catastrophic ebbs and flows. As you can see from the graph, some of those times were tough – with over eight of such world-changing events clustering together over geologically small timespans, forming the catastrophic ‘pulse’. “These events include times of marine and non-marine extinctions, major ocean-anoxic events, continental flood-basalt eruptions, sea-level fluctuations, global pulses of intraplate magmatism, and times of changes in seafloor-spreading rates and plate reorganizations,” the team writes in their paper. These cyclic pulses of tectonics and climate change may be the result of geophysical processes related to the dynamics of plate tectonics and mantle plumes, or might alternatively be paced by astronomical cycles associated with the Earth’s motions in the Solar System and the Galaxy. Luckily for us, the research suggests we have another 20 million years before the next ‘pulse’. 

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