Relive Important Archive Articles

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

Castle Lake Basin

July 16, 2017

Castle Lake fills a plunge-pool at the base of a 300-ft tall cataract at the opposite (east) end of the Great Cataract Group from Dry Falls, above the east end of Deep Lake. A set of steel ladders put in place during the construction of the Columbia Basin Irrigation Project allow for a safe descent into the basin. In the basin are great views of giant potholes, the flood-sheared face of Castle Rock, as well idyllic Deep Lake. The Castle Lake Basin lies along the east end of the Great Cataract Group. At the base of the cataract is lovely blue-green Castle Lake plunge pool nestled into the rock bench below. Castle Lake lies within a single recessional cataract canyon eroded down to a flood-swept, pothole-studded rock bench that stands 100 feet above Deep Lake. This is the same rock bench of Grande Ronde Basalt where dozens of potholes occur at the opposite (western) end of Deep Lake. Castle Rock itself is an isolated butte along the west side of the Castle Lake basin. It is a faceted butte escarpment nearly sheared off by monstrous flood forces moving across the cataract.

How did humans first reach the Americas?

February 21, 2023

During the last ice age, which route was taken by the first humans to reach the Americas, and did they travel by foot, boat or both? Humans first arrived in North America at least 15,500 years ago. Exactly how they got there, however, constitutes one of the longest-standing debates in archaeology. For decades, scientists assumed that people first arrived in the Americas by walking south from the now-flooded land bridge in the Bering Strait that once connected Russia to Alaska when sea levels were lower during the last ice age. But recent evidence suggests that these people were not the first to set foot on the continent. According to the now-dominant “coastal route theory,” that distinction belongs to humans who boated down the Pacific coast several millennia earlier. A 2023 study(opens in new tab), for instance, found that coastal conditions were favorable during two time windows: from 24,500 to 22,000 years ago, and from 16,400 to 14,800 years ago. And while the science is far from settled, the evidence increasingly points to the first Americans arriving by sea or land along the coast. “The pendulum is swinging in support of the coastal corridor being the route taken by the first Americans,” Michael Waters(opens in new tab), director of the Center for the Study of the First Americans at Texas A&M University, told Live Science in an email. “But we still need the smoking gun: an early site along the coast.” Until 20 years ago, the best available archaeological evidence(opens in new tab) suggested that humans first arrived in North America about 13,000 years ago. The rise of the Clovis people — whose 13,400-year-old remains were discovered in Clovis, New Mexico, in the early 1900s — coincided perfectly with the formation of an ice-free corridor along the Rocky Mountains. Scientists assumed that these humans crossed the Bering Land Bridge into what is now Alaska, and then turned south to march onward to New Mexico through that convenient corridor. This remains the prevailing theory as to how the Clovis people made it to the Americas. “It seems very likely that people did arrive from northeast Asia via the ice free corridor once this route was open and viable,” Todd Braje, chair of anthropology at San Diego State University, told Live Science in an email. But recent excavations suggest that the Clovis were not the first Americans. A 2011 paper in the journal Science presented evidence of tools crafted by humans in Texas from up to 15,500 years ago, and a 2021 paper in Science described 23,000-year-old footprints in New Mexico. (However, the footprint date is disputed by a 2022 study in the journal Quaternary Research, which posits that the plant seeds the original team used to radiocarbon-date the footprint layer are problematic.) These “pre-Clovis people” would have had to migrate to America long before the ice-free corridor opened up. “The earliest the inland corridor was open is 14,300 years ago,” Waters said. “It is impossible to have people in Texas and Idaho at 16,000 years ago, and Florida at 14,600 years ago, come through the corridor. They must have come a different way.” How the pre-Clovis people got to America without an inland corridor to take them south from the Bering Strait remains an open question. “With the breaking of the Clovis barrier in the 1990s, we know people were in the Americas prior to at least 14,000 years ago, but when people first arrived and by what route or routes remains unknown,” Braje said. “There are now lively debates on the topic but the bottom line is that no one knows definitely.” The prevailing theory is that the pre-Clovis people arrived by watercraft. “The route taken by the initial migrants was almost certainly along the coast,” said Matthew Des Lauriers(opens in new tab), director of the Applied Archaeology Program at California State University, San Bernardino. Des Lauriers described the pre-Clovis as sophisticated maritime hunter-gatherers, who would have cast off south from the Bering Land Bridge and subsisted on fish and game as they voyaged down the Pacific coast. Ultimately, Des Lauriers said, these intrepid seafarers parted ways. Some pre-Clovis people followed rivers inland, while others continued south as far as Chile. “The ocean would always have provided resources for skilled fishermen and hunters,” Des Lauriers told Live Science in an email. “The most likely scenario is one of coastal fisher-hunter-gatherers moving along the North Pacific Coast.” Recent work from geologists has lent support to the theory that the Clovis people arrived via an inland corridor, while the pre-Clovis people took a coastal route. Beryllium-10 dating of glacial boulders(opens in new tab) along the ice-free corridor suggests that the corridor opened about 13,800 years ago. And studies suggest that a strip of unglaciated land should have existed along the Pacific coast of Alaska and British Columbia 16,000 years ago — prime real estate for a coastal corridor. As the field of ancient genetics has blossomed, multiple studies(opens in new tab) have provided additional evidence that the first Americans arrived between 15,000 and 17,000 years ago. “It is gratifying to see the archaeological and genetic evidence converging to tell the same story,” Waters said. “Finally, we have a much better understanding of the chronology of the opening of the two corridors, and the evidence now supports a coastal migration route.” Nonetheless, physical evidence for both corridors is still lacking. Significant archaeological, genetic and geologic legwork will be necessary before we can firmly point to the lives and times of the first Americans and begin to describe, with confidence, how they arrived in America. “There are very few sites along the Pacific Coast that are pre-Clovis in age, and much work needs to be accomplished to find potential early coastal sites,” Braje said. “We have no definitive answers about when and how people first arrived in the Americas.” Reproduced from an article by Joshua A. Krisch, published in Live Science More on archaeological research into early human migration into the Americas: The Fertile Shore

Bering Land Bridge Formed Surprisingly Late During Last Ice Age

December 27, 2022

By reconstructing the sea level history of the Bering Strait, scientists found that the strait remained flooded and the Bering Land Bridge connecting Asia to North America did not emerge until around 35,700 years ago, less than 10,000 years before the height of the last ice age (known as the Last Glacial Maximum), and not long before humans are thought to have begun migrating into the Americas. The new findings indicate that the growth of the ice sheets—and the resulting drop in sea level—occurred surprisingly quickly and much later in the glacial cycle than previous studies had suggested. “It means that more than 50 percent of the global ice volume at the Last Glacial Maximum grew after 46,000 years ago,” said Tamara Pico, assistant professor of Earth and planetary sciences at UC Santa Cruz and a corresponding author of the paper. “This is important for understanding the feedbacks between climate and ice sheets, because it implies that there was a substantial delay in the development of ice sheets after global temperatures dropped.” Global sea levels drop during ice ages as more and more of Earth’s water gets locked up in massive ice sheets, but the timing of these processes has been hard to pin down. During the Last Glacial Maximum, which lasted from about 26,500 to 19,000 years ago, ice sheets covered large areas of North America. Dramatically lower sea levels uncovered a vast land area known as Beringia that extended from Siberia to Alaska and supported herds of horses, mammoths, and other Pleistocene fauna. As the ice sheets melted, the Bering Strait became flooded again around 13,000 to 11,000 years ago. The new findings are interesting in relation to human migration because they shorten the time between the opening of the land bridge and the arrival of humans in the Americas. The timing of human migration into North America remains unresolved, but some studies suggest people may have lived in Beringia throughout the height of the ice age. “People may have started going across as soon as the land bridge formed,” Pico said. The new study used an analysis of nitrogen isotopes in seafloor sediments to determine when the Bering Strait was flooded during the past 46,000 years, allowing Pacific Ocean water to flow into the Arctic Ocean. First author Jesse Farmer at Princeton University led the isotope analysis, measuring nitrogen isotope ratios in the remains of marine plankton preserved in sediment cores collected from the seafloor at three locations in the western Arctic Ocean. Because of differences in the nitrogen composition of Pacific and Arctic waters, Farmer was able to identify a nitrogen isotope signature indicating when Pacific water flowed into the Arctic. Pico, whose expertise is in sea level modeling, then compared Farmer’s results with sea level models based on different scenarios for the growth of the ice sheets. “The exciting thing to me is that this provides a completely independent constraint on global sea level during this time period,” Pico said. “Some of the ice sheet histories that have been proposed differ by quite a lot, and we were able to look at what the predicted sea level would be at the Bering Strait and see which ones are consistent with the nitrogen data.” The results support recent studies indicating that global sea levels were much higher prior to the Last Glacial Maximum than previous estimates had suggested, she said. Average global sea level during the Last Glacial Maximum was about 130 meters (425 feet) lower than today. The actual sea level at a particular site such as the Bering Strait, however, depends on factors such as the deformation of the Earth’s crust by the weight of the ice sheets. “It’s like punching down on bread dough—the crust sinks under the ice and rises up around the edges,” Pico said. “Also, the ice sheets are so massive they have gravitational effects on the water. I model those processes to see how sea level would vary around the world and, in this case, to look at the Bering Strait.” The findings imply a complicated relationship between climate and global ice volume and suggest new avenues for investigating the mechanisms underlying glacial cycles. In addition to Pico and Farmer, the coauthors include Ona Underwood and Daniel Sigman at Princeton University; Rebecca Cleveland-Stout at the University of Washington; Julie Granger at the University of Connecticut; Thomas Cronin at the U.S. Geological Survey; and François Fripiat, Alfredo Martinez-Garcia, and Gerald Haug at the Max Planck Institute for Chemistry in Germany. This work was supported by the National Science Foundation. Published in Proceedings of the National Academy of Sciences. Reprinted from UC Santa Cruz Newsletter, By Tim Stephens

Unearthing the Secrets of Spokane Valley: A Recap of the IAFI June Jamboree

June 11, 2024

This year’s IAFI June Jamboree delved into the fascinating geological history of Spokane Valley, contrasting it with the iconic Grand Coulee and Dry Falls, explored during last year’s Jubilee. Challenging the Landscape: Unlike the open spaces of Dry Falls, Spokane Valley presented a unique challenge – showcasing evidence of Ice Age Floods within an urban environment. Our chapter tackled this brilliantly, organizing hikes and car caravans departing from convenient public parks and commercial areas. Evening Explorations: The program’s highlights included captivating lectures. Professor Emeritus Dean Kiefer shed light on J Harlen Bretz’s Spokane associates, while renowned naturalist Jack Nesbit brought the story of the first Columbian Mammoth discovered near Latah Creek in the 1800s to life. Celebrating Success: The Jamboree culminated in a relaxed gathering at Mirabeau Meadows. Registrants, leaders, and participants exchanged insights and experiences, with a resounding appreciation for the chapter’s efforts. Comparisons were drawn, highlighting how our Spokane Valley exploration continued the excellence of the Puget Lobe’s outing at Dry Falls last year. A Delicious Finale: The grand finale was a catered Longhorn Barbecue overflowing with delicious food. Everyone left satisfied, with many even taking home doggie bags to savor the flavors afterward. Check out more images from the event in this Google Photo Album. Meet the Masterminds: Linda & Mike McCollum: This dynamic professor emerita and a research geologist duo co-led tours and car caravans, sharing their latest research on the Spokane area’s Ice Age Floods, and shaping the Jamboree’s theme. Michael Hamilton: A gifted geologist, Michael led hikes and the bus trip, encouraging questions and offering honest answers. Don Chadbourne & Chris Sheeran: Don, the chapter treasurer, managed logistics with expertise, while Chris, our media and registration guru, ensured a smooth experience. Melanie Bell Gibbs: A past president and national board member, Melanie oversaw participant check-in and badge distribution. Dick Jensen: Dick handled bus transportation and provided crucial support throughout the Jamboree. Jim Fox: The chapter vice president secured speakers and offered his assistance wherever needed. We also owe a great deal to the participant volunteers who proved invaluable in assisting us in all our efforts. Through the combined efforts of many the IAFI June Jamboree was a resounding success, fostering exploration, education, and a deeper appreciation for the Spokane Valley’s unique geological heritage. Being present with so much information and conversation among such extensive expertise was to witness the scientific process in action. Meeting people from other chapters was particularly nice, putting faces with names we know. We all learned a lot.

Dry Falls Kayaking

July 14, 2022

Dry Falls Kayaking Ice Age Floods National Geologic Trail Most Pacific Northwesterners know how awesomely majestic and stunningly beautiful Dry Falls is, if only from the pictures that seem to show up everywhere. If you haven’t been there in person yet you definitely need to make that trek into central Washington. The drive through the lower Grand Coulee, as awesome as it is, is only the teaser for the view from the Dry Falls Visitor Center. But if you really want to get into the majesty, consider taking a kayak down to Dry Falls Lake or Deep Lake, at the base of those monstrous cataracts. The dirt road to Dry Falls Lake isn’t for the faint of heart, and a good, high clearance SUV is recommended. But paddling the lake near the base of those 400 foot high cliffs is worth the effort. Bordered by reeds and accompanied by waterfowl, an hour-long paddle around the lake is leisurely, relaxing, and totally absorbing. And who knows, you might end up in someone else’s fantastic photo of Dry Falls from the Visitor Center. The road to Deep Lake is paved, so it is a much easier place to get to. And the ramp at the lake makes getting in and out pretty easy… just be careful of the slippery algae on the ramp. Once you’re on the lake an hour’s paddle will take you from an area bordered by rolling hills to a section bounded by high vertical walls. Don’t fall out in this area because there’s nowhere to climb out or beach your boat to climb back in. Still, it’s astoundingly interesting to get up close and see the variety of textures in the basalt walls. Of course, you can also do some great hiking in both areas, though climbing the blade takes quite a bit of effort and confidence, but the view is pretty spectacular. Unfortunately, the way back down isn’t any easier than the way up. Choose your route carefully. Quick Facts Location: Grant County, Washington, United States 99371 MANAGED BY:Washington State ParksWebsite: https://iafi.org/go-do/washington/ Dry Falls is a 3.5-mile-long scalloped precipice with four major alcoves, in central Washington scablands. A Discover Pass is required for vehicle access to state parks for day use. For more information about the Discover Pass and exemptions, please visit the Discover Pass web page.

Asteroid That Decimated the Dinosaurs May Have Struck in Spring

February 23, 2022

Spring may have been when a roughly seven-mile-wide asteroid struck the Earth, immediately triggering the mass extinction that would wipe out 76 percent of known species. That key piece of timing doesn’t come from dinosaurs, but from the fish that swam in the waters dinosaurs drank from. By studying the fossil bones of these fish and comparing them to their modern counterparts, Vrije Universiteit Amsterdam paleontologist Melanie During and colleagues have come to the conclusion that the impact that ended the Age of Dinosaurs most likely occurred in the spring. Like their modern counterparts, ancient sturgeons and paddlefish of the Hell Creek Formation, found in the “Tanis” fossil site in North Dakota, grew in cycles. Those researchers proposed that this place contains critical clues about the first minutes and hours of what transpired after impact—including well-preserved fossil fish that contain asteroid impact debris in their gills. During warmer months when food was plentiful, the ancient fish grew and added more bone tissue just as their modern relatives do. During cooler, harsher months, however, their growth slowed and left a line—called a line of arrested growth, or LAG—in their bones. In addition, the bones of these fish contained signatures from oxygen and carbon isotopes. The geochemical signals in these isotopes were influenced by what the fish were eating and the waters they swam in, a natural phenomenon that has been used by paleontologists to study everything from when early whales took to the seas to what plants ancient herbivores ate. Details of the prehistoric sturgeon and paddlefish bones indicate that these fish had not yet hit the peak of their annual growth spurt, which would be expected during the warmest parts of the year. The carbon isotope ratios in the paddlefish bones also match up with this pattern. If these ancient fish lived according to a similar annual cycle as their living relatives, then the signatures in their bones hint that they perished in spring. The fact that tiny spherules thrown into the air during the impact were found in their gills places the time of death within minutes or hours of the end-Cretaceous impact. Together, these lines of evidence suggest that the impact took place while the Northern Hemisphere was in spring and the Southern Hemisphere was still in winter. Read more in the Smithsonian Magazine article by Riley Black that this was taken from, or a Science Alert article that also recaps the paper published in Nature.

Relive Important Archive Articles

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

Like this:

Members

Happenings

About

Resources

Relive Important Archive Articles

Share this article:

Like this:

Members

Happenings

About

Resources