Sharing the Fascinating Ice Age Floods Story Since 1995

Category: News

Frenchman Coulee Drone Video

Bruce Bjornstad is at it again with his awesome Ice Age Floodscapes drone videos, this one from Frenchman Coulee. Watch it below and visit his Ice Age Floodscapes YouTube channel.for many more.

WA Geology Releases Stunning Lidar Images

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. Click here for the complete Washington State DNR image galleries Mt Adams Lava Flow Outburst Flood Scars West Bar – Giant Ripple Marks Steptoe Butte – Loess Hills Mima Mounds Previous Next

My Hill

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

First People in the Americas – When? How?

First People in the Americas – When? How? When and how did the first people come to the Americas? The conventional story says that the earliest settlers came via Siberia, crossing the now-defunct Bering land bridge on foot and trekking through Canada when an ice-free corridor opened up between massive ice sheets toward the end of the last ice age. But with recent archaeological evidence casting doubt on this thinking, scientists are seeking new explanations. One dominant, new theory: The first Americans took a coastal route along Alaska’s Pacific border to enter the continent. A new geological study provides compelling evidence to support this hypothesis. By analyzing boulders and bedrock, a research team led by the University at Buffalo shows that part of a coastal migration route became accessible to humans 17,000 years ago. During this period, ancient glaciers receded, exposing islands of southern Alaska’s Alexander Archipelago to air and sun — and, possibly, to human migration. The timing of these events is key: Recent genetic and archaeological estimates suggest that settlers may have begun traveling deeper into the Americas some 16,000 years ago, soon after the coastal gateway opened up. The research will be published online on May 30 in the journal Science Advances. “People are fascinated by these questions of where they come from and how they got there,” says lead scientist Jason Briner, PhD, professor of geology in UB’s College of Arts and Sciences. “Our research contributes to the debate about how humans came to the Americas. It’s potentially adding to what we know about our ancestry and how we colonized our planet.”   “Our study provides some of the first geologic evidence that a coastal migration route was available for early humans as they colonized the New World,” says UB geology PhD candidate Alia Lesnek, the study’s first author. “There was a coastal route available, and the appearance of this newly ice-free terrain may have spurred early humans to migrate southward.” The findings do not mean that early settlers definitely traversed Alaska’s southern coast to spread into the Americas: The project examined just one section of the coast, and scientists would need to study multiple locations up and down the coastline to draw firmer conclusions. Still, the work is exciting because it hints that the seafaring theory of migration is viable. The bones of an ancient ringed seal — previously discovered in a nearby cave by other researchers — provide further, tantalizing clues. They hint that the area was capable of supporting human life at the time that early settlers may have been passing through, Briner says. The new study calculates that the seal bones are about 17,000 years old. This indicates that the region was ecologically vibrant soon after the ice retreated, with resources including food becoming available. Co-authors on the research included Briner; Lesnek; Charlotte Lindqvist, PhD, an associate professor of biological sciences at UB and a visiting associate professor at Nanyang Technological University; James Baichtal of Tongass National Forest; and Timothy Heaton, PhD, of the University of South Dakota. A landscape, touched by ice, that tells a story To conduct their study, the scientists journeyed to four islands within the Alexander Archipelago that lie about 200 miles south/southeast of Juneau. The team traveled by helicopter to reach these remote destinations. As soon as the researchers arrived, Briner knew that the islands had once been covered by ice. “The landscape is glacial,” he says. “The rock surfaces are smooth and scratched from when the ice moved over it, and there are erratic boulders everywhere. When you are a geologist, it hits you in the face. You know it immediately: The glacier was here.” To pinpoint when the ice receded from the region, the team collected bits of rock from the surfaces of boulders and bedrock. Later, the scientists ran tests to figure out how long the samples — and thus the islands as a whole — had been free of ice. The researchers used a method called surface exposure dating. As Lesnek explains, “When land is covered by a glacier, the bedrock in the area is hidden under ice. As soon as the ice disappears, however, the bedrock is exposed to cosmic radiation from space, which causes it to accumulate certain chemicals on their surface. The longer the surface has been exposed, the more of these chemicals you get. By testing for these chemicals, we were able to determine when our rock surfaces were exposed, which tells us when the ice retreated. “We use the same dating method for huge boulders called erratics. These are big rocks that are plucked from the Earth and carried to new locations by glaciers, which actually consist of moving ice. When glaciers melt and disappear from a specific region, they leave these erratics behind, and surface exposure dating can tell us when the ice retreated.” For the region that was studied, this happened roughly 17,000 years ago. The case for a coastal migration route In recent years, evidence has mounted against the conventional thinking that humans populated North America by taking an inland route through Canada. To do so, they would have needed to walk through a narrow, ice-free ribbon of terrain that appeared when two major ice sheets started to separate. But recent research suggests that while this path may have opened up more than 14,000 years ago, it did not develop enough biological diversity to support human life until about 13,000 years ago, Briner says. That clashes with archaeological findings that suggest humans were already living in Chile about 15,000 years ago or more and in Florida 14,500 years ago. https://youtu.be/CmxhFgpIacI The coastal migration theory provides an alternative narrative, and the new study may mark a step toward solving the mystery of how humans came to the Americas. “Where we looked at it, the coastal route was not only open — it opened at just the right time,” Lindqvist says. “The timing coincides almost exactly with the time in human history that the migration into

Waning Pleistocene Ice Sheet

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.

First Peoples

Ice-Free Corridor Human Migration to Americas R e e x a m i n e d Humans In Americas 30,000 years ago??? 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. 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.

The Grand Coulee – A Floods Poem

THE GRAND COULEE – A Floods Poem THE GRAND COULEE Older than legends,Younger than mountains,The earth remembersThe Great Inland Sea. And that Sea emptiedIn torrential furyNever imaginedEven in dreams. Down through the canyons,Flood of all riversCarving the couleesTime, time again. Roiled surging waters,Thunder of thunders,Swift toward the oceanReshaping the plain. Gone with the glaciersIs the great Lake Missoula,Gone from remembrance,Like mist in the wind. Yet the story is etchedIn the canyons and couleesLeft for those who imagineTo seek and to find. David Wahl January 4, 2002 Lower Grand Coulee Upper Grand Coulee at Steamboat Rock (left)

Trovants

Geology Can Be Weird – Trovants Trovants Are Stones That Seem to Grow, Move and Reproduce. By: Jennifer Walker-Journey  |  Jun 21, 2022 | HowStuffWorks/Science/Environmental Science/Earth Science/Geology/Geologic Processes Trovants such as these are found only in Romania and have become such a tourist attraction that they are protected by UNESCO. WIKIMEDIA COMMONS (CC BY SA 3.0)Just when we think we’ve seen it all, Mother Nature throws yet another oddity our way. Welcome to the wondrous world of the geological manifestations known as trovants. These rare bulbous, budging boulders are only found in a small town in Romania called Costesti. So fantastical are these trovants, they’ve found a place in local folklore. Some say they grow, walk and even give birth to baby trovants. Science says they’re probably right. What Are Trovants? Trovants are spherical and slightly irregular-shaped rocks. They can be as small as less than an inch, or a couple of millimeters, in diameter and weigh only a few grams, or they can soar up to 15 feet (4.5 meters) high and weigh several tons. These odd, gravity-defying boulders have baffled observers since the 18th century with many a curious soul suspecting they were dinosaur eggs, plant fossils or even alien pods. Scientists believed trovants to be a type of concretion — a mound of mineral matter (specifically gritstone and conglomerates) embedded within rock layers of limestone, sandstone or shale. They often form from minerals precipitating, or settling, out of water collected around a nucleus of pebble, leaf, shell, bone or fossil. However, in 2008, the International Geological Congress in Oslo claimed trovants were incorrectly classified as concretions because there was no mineral difference between the stones and the sandstone beds on which they sat. There was also no distinct nucleus inside them. Whatever they are, scientists believe that based on their makeup and locale atop the sands, these weird stones are older than man — shaped by earthquakes around 5.3 million years ago, during the Middle Miocene sub-epoch. The surrounding sands also suggest the area was an ancient marine environment, which may explain why bivalve and gastropod fossils can sometimes be found in them. These Rocks Can Grow and Multiply Another oddity about trovants — they secrete cement. This talent makes some people think they may be living creatures and not simply rocks. This cement seepage occurs after a heavy rain shower. When trovants absorb the rain’s minerals, the minerals come in contact with the chemicals already present in the stone, causing a pressure reaction that makes the rocks grow in girth. It’s not something you can see happening. Researchers say the deposition rate for trovants is roughly 1.5 to 2 inches (4 to 5 centimeters) every 1,000 years. This same phenomenon is what causes trovants multiply or “reproduce,” as some might say. When a new growth bauble emerges, likely from water affecting only one side of the rock, and gets big enough, it can break off from the “parent” rock and create baby trovants. Like a Rolling Stone Some people also believe that trovants can “walk,” much like the so-called sailing stones of Death Valley that appear to drift across the flat desert landscape on their own. One researcher allegedly filmed trovants for two weeks and claimed one moved about one-tenth of an inch (2.5 millimeters). While many academics are skeptical about “trovant walking” claims, they don’t deny the possibility that the heating or cooling of the soil could cause movement among the stones. Where Can I See a Trovant? Trovants are almost exclusively found in Romania’s Valcea County at the sand quarry near the Costesti village, along the Gresarea Brook, or in the neighboring Otesani village. To protect these unusual geological specimens, the “Muzeul Trovantilor” or Trovants Museum Natural Reserve, was developed in Valcea County, Romania, in 2004, and is now protected by UNESCO.

Bonneville Flood Video

Shawn Willsey recently put together an overview presentation on the Bonneville flood that he wanted to share with IAFI.