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Chicxulub Asteroid Tsunami ‘Megaripples’

July 14, 2021

In what may be the most dramatic mass extinction in Earth’s history, an asteroid impacted our planet 66 million years ago near what is now Chicxulub on the Yucatan Peninsula. The resulting hellscape extinguished 75 percent of then living species – including all non-avian dinosaurs. Over the last few years, scientists have discovered many more traces of this cataclysmic impact, providing us with ever greater details of its extreme aftermath – from world-encircling dust to wildfires up to 1,500 kilometers (930 miles) from the impact site. In 2019, a team found fossil records of the immediate hours after, including evidence of debris swept up by the resulting tsunami. Now, researchers have discovered enormous megaripples engraved by the tsunami in sediments 1,500 meters (5,000 feet) below what is now central Louisiana. By analyzing seismic imaging data for central Louisiana, gained from a fossil fuel company., the team determined the imprinted ripple crests form a straight line right back to the Chicxulub crater and their orientation is consistent with the impact. These megaripple features have average wavelengths of 600 meters and average wave heights of 16 meters making them the largest ripples documented on Earth. Compare that to the largest Camas Prairie megaripple at 289m x 17m. Modelling of this monstrous tsunami suggests its waves would have reached a staggering 1,500 meters high (nearly 1 mile) after the Richter scale 11 megaearthquake triggered by the collision. The aftereffects would have been particularly devastating in the regions surrounding the impact site, sweeping sea life onto land and land life into the sea. “Tsunami continued for hours to days as they reflected multiple times within the Gulf of Mexico while diminishing in amplitude,” the team wrote. What carved out the ripples we can still detect today were the forces from the massive walls of water smashing into the shallow shelf near the shores, and reflecting back towards their source. Excerpted from: sciencealert.com/tsunami-megaripples-from-the-dinosaur-killing-asteroid-impact-discovered-in-louisiana Read another article at: https://www.sciencetimes.com/articles/32252/20210713/dino-killer-space-rock-left-fossilized-megaripples-mile-high-giant.htm

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

October 15, 2023

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

13,000 Year-Old Human Footprints Found on BC Island

March 29, 2018

Big feet. Little feet. A heel here. A toe there. A digitally enhanced photo of a footprint found at Calvert Island, British Columbia that researchers dated to 13,000 years old. Credit Duncan McLaren Stamped across the shoreline of Calvert Island, British Columbia, are 13,000-year-old human footprints that archaeologists believe to be the earliest found so far in North America. The finding, which was published Wednesday in the journal PLOS One, adds support to the idea that some ancient humans from Asia ventured into North America by hugging the Pacific coastline, rather than by traveling through the interior. “This provides evidence that people were inhabiting the region at the end of the last ice age,” said Duncan McLaren, an anthropologist at the Hakai Institute and University of Victoria in British Columbia and lead author of the study. “It is possible that the coast was one of the means by which people entered the Americas at that time.” Dr. McLaren and his colleagues stumbled upon the footprints while digging for sediments beneath Calvert Island’s beach sands. Today, the area is covered with thick bogs and dense forests that the team, which included representatives from the Heiltsuk First Nation and Wuikinuxv First Nation, could only access by boat. At the close of the last ice age, from 11,000 to 14,000 years ago, the sea level was six to ten feet lower. The footprints were most likely left in an area that was just above the high tide line. “As this island would only have been accessible by watercraft 13,000 years ago,” Dr. McLaren said, “it implies that the people who left the footprints were seafarers who used boats to get around, gather and hunt for food and live and explore the islands.” They found their first footprint in 2014. While digging about two feet beneath the surface in a 20-square-inch hole, they saw an impression of something foot-shaped in the light brown clay. In 2015 and 2016, they returned and expanded the muddy pit. They discovered several more steps preserved in the sediment. The prints were of different sizes and pointed in different directions. Most were right feet. When the team was finished they had counted 29 in total, possibly belonging to two adults and a child. Each was barefoot. The researchers think that after the people left their footprints on the clay, their impressions were filled in by sand, thick gravel and then another layer of clay, which may have preserved them. Using radiocarbon dating on sediment from the base of some footprint impressions, as well as two pieces of preserved wood found in the first footprint, Dr. McLaren and his team found them to be 13,000 years old. That would make them the oldest preserved human footprints in North America. “It’s not only the footprints themselves that are spectacular and so rare in archaeological context, but also the age of the site,” said Michael Petraglia, an archaeologist from the Max Planck Institute for the Science of Human History in Germany who edited the paper for PLOS One but was not involved in the work. “It suggests an early entrance into the Americas.” Dr. Petraglia said the footprints also provided strong evidence for the coastal movement hypothesis and he added that they may have traveled the so-called “Kelp Highway,” a hypothesis that underwater kelp forests supported ecosystems down the North Pacific coast that helped ancient seafaring people hunt, develop and migrate. “The work is important because it shows the ‘real’ people, not just artifacts or skeletal remains,” said Steve Webb, a biological archaeologist at Bond University in Australia. “However, the footprints are limited in number and don’t shed light on activities or movement that tell us very much.” He added that future hunts for footprints should keep in mind that not everyone from this time period walked around barefoot. If anthropologists are too busy searching for soles, toes and arches, they might miss clues from those who wore animal skin shoes. Reprinted from New York Times – Earliest Known Human Footprints in North America Found on Canadian Island By NICHOLAS ST. FLEUR, March 28, 2018

Hiking Drumheller Channels

July 14, 2022

Hiking Drumheller Channels Ice Age Floods National Geologic Trail There are scads of hiking trails all through Drumheller Channels National Natural Landmark. On a cloudy day in early June we took off on a couple of exploratory hikes that were simply amazing. We first proceeded south from the parking lot at Lower Goose Lake, running through late Spring wildflowers, eventually looking for one of Bruce Bjornstad’s geocaches. We wandered over hills and down into deeper valleys, always surrounded by the towering walls of basalt defining that section of Drumheller Channels. Along the way we found an area of apparent Kolk depressions with odd spires of basalt poking up out of the middle of a central mound. Soon we passed through a reedy area that bounded the southern edge of Lower Goose Lake. We continued on south to the edge of Black Lake where the geocache was supposed to be, but after 20 minutes with 4 of us looking in the area of the GPS coordinates, we finally decided the cache was no longer there and headed back. The hike was easy, very pleasant, and mercifully cool due to the cloudy morning. We then drove north across the O’Sullivan Dam, and back south through Columbia National Wildlife Refuge to the W. McManamon Road entrance to Crab Creek Marsh Unit #3 and the Basalt Columns at Drumheller Trailhead, the kickoff point to go to the top of “Nick’s Columns”. Nick Zentner’s videos about the columns are great, but the blooper where his rock hammer falls down between columns is priceless. We just had to see those columns for ourselves, and we weren’t disappointed. It’s interesting how only the columns along the edge are free standing, while those inboard are packed around with sediment. The little rain the area gets probably washed the sediment out of the spaces between the bordering columns. After walking around for a while we made our way back to the car and drove to the Drumheller Channels National Natural Landmark overlook for a final sweeping viewpoint. The entire area is huge and worth several days of exploring, but it’s also pretty easy to have a great time in just a few hours. This is a place you just have to experience. Quick Facts Location: Adams County, Washington 99371

Williams Lake Cataract Video

November 8, 2016

Williams Lake Cataract is an ancient, dry waterfall left behind along the Cheney-Palouse Scabland Tract in eastern Washington after Ice Age flooding recessionally ripped out underlying basalt to produce this massive cataract. Video produced by Bruce Bjornstad, Ice Age Floodscapes

The Cerutti Mastodon Site – A Bretz Type Controversy of Our Time

May 3, 2018

In March, while visiting San Diego, I went to the San Diego Museum of Natural History in Balboa Park and toured the remarkable Cerutti Mastodon Site exhibit. This controversial exhibit of a mastodon site is notable for its claim that the mastodon’s bones were broken by humans 130,000 years ago, making it far older than any other such site in North America. The signs at the beginning of the exhibit read as follows; “The Cerutti Mastodon discovery. A San Diego find reveals the earliest evidence of of human life in North America. In 1992, paleontologists from the San Diego Natural History Museum were surveying a highway construction site to identify and salvage any fossils that might be unearthed. “Field paleontologist Richard Cerutti spotted some bones and tusks. Exploring further, the team discovered that these were bones of a mastodon-an extinct relative of elephants. “But Richard noticed something unusual. The bones were mysteriously broken and the pieces separated. “It took 22 years for scientists to solve the riddle. Once they did, they realized that this local site is evidence of human presence on this continent 130,000 years ago-much earlier than we thought possible. “In 2014, scientists made a new discovery about the age of the Cerutti Mastodon Site. How did this happen? Scientists figured out the age of the mastodon bones using radiometric dating. It’s a way of telling how old a rock or fossil is by measuring its radioactive isotopes. “A radioactive isotope transforms into an isotope of a different element over time. If you know the rate at which the “parent” isotope transforms into its “daughter” isotope, measuring the parent-daughter ratio tells you how old the material is. “Scientists used a method that measures the ratio of the radioactive isotope uranium-234 to its daughter isotope thorium-230. Dramatic improvements in this method have made it a highly accurate means of dating very old materials- up to 500,000 years. In 2014, scientists used this method to date bones at the Cerutti Mastodon Site. “The results were clear. The bones are approximately 130,000 years old.” More than two decades after the Cerutti mastodon’s discovery in southern California in 1993, USGS scientist Dr. James Paces was sent several bones of unknown age. The specimens were important because they came from a site with abundant evidence of processing by ancient humans. Advances in analytical capabilities and the understanding of processes that incorporate natural uranium and its decay products in fossil bone provided archaeologists with a radiometric dating tool that, at least in some cases, could confidently and accurately determine ages for these older materials. After analyzing nearly 100 subsamples from multiple specimens, Dr. Paces determined that the mastodon bones—which were still fresh when someone fractured them using hammerstones and rock anvils—were covered with sediments 131,000 years ago, give or take about 9,000 years. This result indicates that some form of archaic humans arrived in the Americas more than 100,000 years earlier than scientists had thought possible. Following the dating of the bones officials at the Natural History Museum began making plans for a permanent exhibit about the discovery. The exhibit opened in 2017. It is very thorough and includes bones, alleged hammerstones, and anvil rocks from the original mastodon site as well as numerous photos and interpretive panels. When J Harlen Bretz first announced in the 1920’s his theory that the scablands of eastern Washington State had been carved out by a cataclysmic flood he met stiff opposition. What he was proposing was so far out of the mainstream of geological thinking of the time that many scientists couldn’t accept it. Schooled in uniformitarianism they believed that earth’s landforms were all created by slow gradual processes operating over time and that an event of the magnitude Bretz was proposing just wasn’t possible. They tried to come up with alternative explanations for the facts Bretz presented that fit in with their current frame of reference. Yale University geologist Richard Foster Flint famously said of certain flood features in the scablands that they presented “a picture of leisurely streams with normal discharge.” The claim by San Diego’s Natural History Museum that the Cerutti site is 130,000 years old is likewise far outside what many scientists of our time are ready to accept. Other similar sites are much younger. For example Sequim’s famous mastodon site is only 13,800 years old. If the San Diego Natural History Museum is correct it totally rewrites the history books about humans in North America. It places humans in North America during a previous interglacial period. It would establish that humans had long since been in North America during the time of the comparatively recent ice-age floods. Critics of the Natural History Museum, and there are many, point to things like what they consider to be a lack of lithics from the site. Others speculate that the signs of bone breakage observed at the site may have been caused by some other creature besides humans or by modern day construction equipment. But the Natural History Museum counters that none of the critics have provided a satisfactory alternative explanation for the evidence that they’ve presented. Cerutti and his team of researchers and the San Diego Natural History Museum remain unequivocal in their conclusion: The Cerutti Mastodon Site is a 130,000 year old archaeological site. – by Mark Sundquist, Puget Lobe Chapter “Ideas without precedent are generally looked upon with disfavor and men are shocked if their conceptions of an orderly world are challenged.” J Harlen Bretz 1928 “Extraordinary claims require extraordinary evidence – each aspect requires the strongest scrutiny,” Chris Stringer

Relive Important Archive Articles

Williams Lake Cataract Video

The Cerutti Mastodon Site – A Bretz Type Controversy of Our Time

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