Gorge-ous Gathering – 2025 IAFI Membership Meeting
2025 IAFI Membership MeetingGorge-ous Gathering Celebrating the 30th anniversary of Ice Age Floods Institute The annual IAFI Membership Meeting is coming to the Columbia Gorge this May 2-4, 2025, and both members and the public are cordially invited to come enjoy some of the best and most interesting nature experiences the Gorge has to offer. Several of the events are already full but there are still opportunities to explore geology and winery field trips and enjoy an entertaining presentation by Nick Zenter of YouTube fame. Gorge-ous Gathering Event check-ins begin each day at 8:00 AM at the Columbia Gorge Discovery Center Registrations are now closed to give us time for preparations Friday, May 2nd, Spring Wildflower Walk Prepare to be captivated as Barbara Robinson, a renowned native plants expert, leads you on a spectacular Wildflower Walk through Tom McCall Preserve on the Rowena Plateau. Located in the transition zone between the moist, heavily-forested west side of the Cascades and the drier bunch grass prairies of the east, the easy Plateau Trail immerses you in a vibrant tapestry of springtime wildflowers that cover grasslands full of arrowleaf balsamroot, lupine, bachelor’s button, and other spectacular wildflowers blooming at your feet. You’ll meander through breathtaking panoramas of the Columbia River Gorge unfolding before you, imagining the raw power of nature that created the enigmatic mound-and-swale topography and kolk pond landforms sculpted by ancient forces of volcanic eruptions and Ice Age floods that flowed 200 feet above your head. You’ll meet Barbara at 9:30AM at the Discovery Center and follow her to Rowena Crest parking circle at 10:00 AM, Friday. May 2nd (Google Maps link) for an unforgettable magical adventure on the Rowena Plateau. Remember to stay on marked trails, dress for probable strong winds, avoid poison oak, and that dogs are not permitted. Friday, May 2nd, Embark on a Vineyard/Winery “Journey Through Terroir” Experience the magic of the Columbia Gorge Wine Region with renowned soil scientist and vineyard consultant, Alan Busacca. This exclusive bus tour takes you deep into the heart of this unique region, where dramatic landscapes and diverse microclimates create wines of extraordinary character. You’ll visit stunning vineyards, sample award-winning wines, and uncover the fascinating science behind their unique flavors. Learn how terroir – diverse soils, extreme rainfall gradients, temperature, elevation and aspect – all contribute to the distinctive taste of each wine. From lush, forested hillsides to sun-drenched high-desert slopes, this is your chance to experience the incredible diversity of this “World of Wine in Forty Miles.” and taste the sensory adventure of the Columbia Gorge firsthand. May 2nd, 9:30AM-4:00PM, bus loads 9:30AM at the Discovery Center. Click here for the itinerary and route map details IAFI Membership Meeting: 5:00-5:30 – Discovery Center Auditorium – Everyone Welcome Pasta buffet dinner: 5:30-6:45 – Discovery Center Basalt Rock Cafe – Pre-registration required Friday, May 2nd, Unveiling the Gorge field trip The walls of the Columbia Gorge expose layer upon layer of similar appearing Columbia River Basalt. But exposed within those walls are features that tell unusual stories of geologic events, cultural history and inspire imaginative tales. On this field trip geologist Lloyd DeKay will lead you to several stops to explore and discuss those features and their stories as we do a 50-mile bus loop through some of the most spectacular scenic vistas the Gorge has to offer. Maars, lahars, pillows, petroglyphs, even an exotic side trip, plus much more will expand your vision and tickle your imagination. Lunch at a scenic overlook May 2nd, 9:30AM-4:00PM, bus loads 9:30AM at the Discovery Center. Click here for the route map details Friday Evening, May 2nd, Nick Zentner Presents – “Bretz, Pardee, and the Ice Age Floods” Prepare to be enthralled and captivated as Nick Zentner (of YouTube fame!) brings to life the epic tale of J Harlen Bretz and Joseph Pardee, the visionary geologists who deciphered the colossal Ice Age Floods. Their story is one of scientific rebellion and groundbreaking discovery, and Nick’s dynamic presentation of his recent collaboration to document and share the field notes and journal revelations of Bretz and Pardee will leave you awestruck. May 2, 7:00 PM. Saturday, May 3rd, Ice Age Floods Gorge Geology field trip Ice Age Floods Gorge Geology Field Trip – Explore evidence of the Ice Age Floods in the Columbia Gorge with guidance from USGS geologists Jim O’Connor and Richard Waitt. This field trip will examine the geology of the Columbia River Gorge, especially the effects of the Ice Age Missoula floods, examining key sites and discussing the latest research. The Columbia River Gorge is the Columbia River’s long-held path through the volcanic arc of the Cascade Range. Here, the myriad routes of the dozens of scabland floods were confined to a single path, forced by gorge constrictions to flow depths as great as 300 m. The intense flood hydraulics left large, coarse boulder bars in the valley bottom and bedded slackwater deposits far up tributary valleys. Taking advantage of the simpler situation of single route, O’Connor and Waitt have been examining the stratigraphy, chronology, and hydrodynamics of Missoula flood features in the gorge for decades to gain a ‘beyond the scablands’ perspective on ice-age floods in the Columbia River basin. Learn more about the Missoula Floods, explore dramatic flood landforms, and enjoy beautiful vistas, lunch at the Deschutes River Park, and a no-host afternoon recap at Maryhill Winery. May 3rd, 9:00AM – 4:00PM, buses load 9:00AM at the Discovery Center. Click here for the route map details Sunday, May 4th, Unveiling the Gorge repeat field trip. The walls of the Columbia Gorge expose layer upon layer of similar appearing Columbia River Basalt. But exposed within those walls are features that tell unusual stories of geologic events, cultural history and inspire imaginative tales. On this field trip, geologist Lloyd DeKay will lead you to several stops to explore and discuss many of those features and their stories as we do a 50-mile bus loop through some of the most spectacular scenic vistas the Gorge has to offer. Maars, lahars, pillows, petroglyphs, even an exotic side trip, plus
Discovering the Telford Tract: A Hidden Gem in the Channeled Scablands
Traveling east along Lake Roosevelt from the Grand Coulee brings you closer to an area steeped in geological and historical intrigue. This journey not only unveils the legacy of ancient Glacial Lake Columbia but also leads to one of the most captivating sections of the Channeled Scablands: the Telford Tract. A critical player in the narrative of Ice Age floods, the Telford Tract offers a striking example of the power and scope of these ancient cataclysmic events. The Role of Glacial Lake Columbia The current Lake Roosevelt occupies much of the previous western Glacial Lake Columbia area, a massive lake formed when glacial ice blocked the Columbia River’s southwestward flow. The lake’s height and timing had a dramatic influence on the routes taken by the incoming Glacial Lake Missoula floodwaters. A portion of these immense floods, among the largest known in Earth’s history, surged south through the Telford region, carving canyons, depositing sediments, and shaping the land into what we now call the Channeled Scablands. J Harlen Bretz, the geologist who first described the scablands in detail, outlined these pathways or “tracts” in his seminal 1928 paper, The Channeled Scabland of Eastern Washington. Among the four major scabland tracts Bretz identified, the Telford-Crab Creek Tract is particularly significant for its geological features and historical context: “The Telford-Crab Creek scabland tract…heads in the vicinity of Telford station…as wide as the Cheney-Palouse River tract…convergence of all these (and of all but one of the Cheney-Palouse River divergences) occurs in a wide shallow structural sag (Quincy Basin) in the western part of the plateau. In this basin is the largest single area of gravel left by the glacial waters…There is continuous scabland northward from all channel heads of this tract across the plateau divide to the limits reached by the ice sheet.” Exploring the Telford Tract Today The Telford Tract, adjacent to the Lake Roosevelt National Recreation Area, provides an unparalleled opportunity to witness the scars of Ice Age floods. Once a 900-acre homestead, the tract’s eroded flood channels and gravel deposits serve as a testament to the massive forces that shaped this region. Managed by the Bureau of Land Management, the Telford Recreation Area invites visitors to explore this geological marvel. Hiking trails weave through remnants of these ancient waterways, offering a chance to immerse yourself in one of the major routes of the Missoula Floodwaters. Check out these resources to help plan your visit: BLM Telford Recreation Area and Washington Trails Association: Telford Recreation Area Beyond Telford: Exploring Upper Crab Creek For those looking to expand their journey through this region, the Telford Tract’s channels eventually connect to Crab Creek, another iconic feature shaped by glacial waters. The Upper Crab Creek Field Trip offers a deeper dive into this fascinating landscape, combining geological exploration with breathtaking scenery. In 2013 Karl Lillquist and Jack Powell created an Upper Crab Creek Field Trip guide for the Ellensburg Chapter of the Ice Age Floods Institute. A Landscape Worth Protecting The Telford Tract exemplifies the dynamic history of the Channeled Scablands and the profound environmental changes brought about by Ice Age floods. As part of the Ice Age Floods National Geologic Trail, this area’s preservation ensures that future generations can continue to learn from and appreciate its unique geological story. Whether you are a geology enthusiast, history buff, or outdoor adventurer, the Telford Tract promises an unforgettable experience. This landscape, shaped by forces beyond imagination, stands as a humbling reminder of nature’s power and its enduring impact on the Earth’s surface.
IAFI 2024 YEAR-IN-REVIEW
A summary of IAFI’s 2024 activities for our members and other interested people. This is our 8th year preparing a Year-in-Review report for you, our members. We appreciate your continued support, friendship and membership. Gary Ford – IAFI President, January 4, 2025 INSTITUTE MEMBERSHIP Our members provide most of our support and much of the reason for the various materials, activities and events we provide. In 1996, we started with 11 members. At the end of 2024, we have 587 members (451 memberships). In addition to the members in the IAFI states (WA, OR, ID, MT), we have members in 16 other states as well as BC Canada and Loerrach, Germany (which is in the very southwest of Germany near Basel and the Swiss Border). West of the Mississippi we have members in CA, NV, AZ, WY, TX, AK, NM and OK. East of the Mississippi there is love of ice age floods in MD, GA, IL, TN, MA, FL, VA and PA. INSTITUTE BOARD PROJECTS IAFI work activities occur at both the Institute Board of Director level and at the Chapter level. Projects at the Institute board level generally benefit more than one chapter or do work that all chapters might not be able to do by themselves. Listed below are some of the recent projects the Institute Board of Directors has worked on: The Education Committee is working on a curriculum for four 20-minute floods videos for a 4th grade audience The Membership Committee developed a catalog of speakers for the chapters to use for their member programs. The Board works closely with the National Park Service (NPS) Program Manager for the Ice Age Floods National Geologic Trail. The intent is to help the Trail Manager with projects related to the development of the Trail. The Board has completed IAFI and Chapter history summaries in preparation for next year’s 30th anniversary. Our webmaster keeps our website (iafi.org) fresh and stimulating. He also, with support from the chapters, issues the Pleistocene Post Newsletter four times a year. This year the Cheney-Spokane Chapter created a significant amount of new content for the website, including a page with geolocated maps of J Harlen Bretz’s and Joseph Pardee’s field notes. ANNUAL MEMBERSHIP MEETING This year the annual IAFI membership meeting and field trip was hosted by the Cheney-Spokane Chapter and was held in the Spokane Valley area. Approximately 100 people attended the event. Follow this link for a summary of that event. 2024 CHAPTER PROGRAMS Outreach to inform and educate the public about the Ice Age Floods and their long-lasting impact on our area is a key part of the IAFI mission. Our local chapter programs are possibly the most effective way we meet this challenge. Three of the more important ways we help people learn about the Ice Age Floods are with lectures, field trips and hikes. LECTURES, FIELD TRIPS AND HIKES In 2024 we had 37 in-person lectures attended by over 1425 people. Many more people viewed lectures when they were posted on YouTube. We conducted 22 field trips with 735 attendees and three chapters sponsored 7 hikes with 106 attendees. PRESENTATIONS TO K-12 STUDENTS A number of people from the Lake Lewis Chapter help with education programs at The Coyote Canyon Mammoth Site (MCBONES) near Kennewick. This was a record year for tourism at the site. Over 4300 visitors, most of them K-12 students, learned about the ice age floods and megafauna extinction. Palouse Falls Chapter: Had a booth at STEAM (Science/Technology/Engineering/Arts/Math) night at Colton School. Lower Grand Coulee Chapter: Assisted with a presentation at the Ice Age Floods Fest at Dry Falls aimed at educating children on the Ice Age Floods story (350+ attendees). INVOLVEMENT WITH PROFESSIONAL ORGANIZATIONS AND UNIVERSITYS Cheney-Spokane Chapter: Hosted a booth at the Geological Society of America meeting in Spokane during May which was attended by several thousand professionals. The Chapter vice president led a two-day trip which was attended by a dozen of the leading professionals on the ice age floods. Wenatchee Chapter: Assisted Dr. Vic Baker with his University of Arizona graduate student trip to the Scablands. Columbia Gorge Chapter – Co-led a number of field trips sponsored by the Oregon State University Extension Master Naturalist Program. Coeur Du Deluge Chapter – Led programs for the Idaho Native Plant Society. All chapters routinely recruit extremely knowledgeable speakers from universities or state/federal agencies so we are presenting the most current information to our members. PRESENTATIONS FOR COMMUNITY EVENTS Cheney-Spokane Chapter – In February, the chapter talked with over 100 people at Great Outdoors Expo Exhibit in Spokane. Presented four lectures at Spokane County Library units. All four talks had standing room only. The library district asked the chapter to do four more talks in 2025 which have been scheduled. Columbia River Gorge Chapter – Completed work on the Cherry Orchard Trail Recording and Dedication. Ellensburg Chapter: had information booths at three Ellensburg Farmers Markets. Spoke with about 300 people. Lower Grand Coulee Chapter: Had a booth at the Quincy Farmer Consumer Awareness Day with IAFI talks and tours, videos and information displays. 200+ attendees. Developed a 3-D topographic model with lights of the floods area for use at community events. Palouse Falls Chapter: Presented lecture on the floods and conducted a tour at the Sandhill Crane Festival. Wenatchee Chapter: Co-led a tour at the Sandhill Crane Festival and participated in FCAD Farmer Consumer Awareness days in Quincy. PARTNERSHIPS AND COLLABORATION WITH OTHER ORGANIZATIONS We are always looking for other organizations to work with. This is a great way to share resources and knowledge. Listed below are some of the organizations we have worked with: Wenatchee – Wenatchee Valley Museum and Cultural Center, Port of Quincy, Othello Sandhill Crane Festival Coeur Du Deluge – Idaho Master Naturalist Program, Idaho Native Plant Society Lake Lewis– MCBONES Mammoth Site, Friends of Badger Mountain, Benton County Parks, The Hanford Reach Interpretative Center, Visit Tri-Cities, East Benton County Historical Museum, Franklin County Historical Museum Cheney-Spokane – Spokane Riverfront Park board,
Geologists predict an Undersea volcano off the Oregon coast could erupt this year
Scientists say Axial, an undersea volcano off the coast of Oregon is probably going to erupt in 2025. The volcano, known as Axial, is a seamount 300 miles (480 kilometers) west of Cannon Beach, Oregon. The Axial seamount erupts regularly — it rumbled to life in 1998, 2011 and 2015, according to a blog by scientists monitoring the seamount — and it doesn’t pose a threat to people. But because of the seamount’s regular activity and its relative proximity to land, researchers made it the site of the world’s first underwater volcano observatory, known as the New Millennium Observatory. Now, the monitors at Axial are showing that the surface of the seamount is inflating — a sign of moving magma that likely presages an eruption, William Chadwick, a geologist at Oregon State University who studies the volcano and its nearby hydrothermal vents, reported at the annual meeting of the American Geophysical Union in December 2024. The volcano’s surface has now risen to 95% of what it was before the 2015 eruption, Chadwick reported. The activity follows a period of quiet between 2015 to 2023, during which the seamount barely budged. The new rise began in the fall of 2023 and increased in January 2024, with the ground moving upward at a rate of about 10 inches (25 centimeters) per year as of mid-2024. This inflation was accompanied by swarms of hundreds of small earthquakes. Since then, the inflation rate has stabilized, Chadwick reported in his blog. “The rate of inflation at Axial has been steady for the last 6 months and the rate of seismicity has moderated,” he wrote. “An eruption does not seem imminent, but it can’t do this forever.” He and his co-author Scott Nooner, a geophysicist at the University of North Carolina Wilmington suspect that the volcano will erupt before the end of 2025. The scientists are hopeful that their prediction is correct, because the well-monitored Axial is a promising location to work out the patterns a volcano experiences before eruption. The fact that the volcano has recently erupted several times over two decades – rather than once in centuries, like many volcanoes – makes discerning patterns easier. Researchers are also more comfortable offering tentative predictions for a volcano that doesn’t threaten life or property, because there are no downsides to being wrong. Volcanologists can currently make accurate short-term predictions of eruptions, but according to the Smithsonian Global Volcanism Program, predictions are rarely reliable more than a few days in advance. Reprinted from Live Science News, article By Stephanie Pappas
Ancient ‘land bridge’ that connected Siberia to US wasn’t what it seems
The boggy landscape of the Bering land bridge may have allowed some ice age animals to cross easily, while others stayed in Asia. The Bering land bridge that spanned between Siberia and Alaska during the Ice Age was more of a Bering land bog, new research finds. The discovery could help explain why some animals, such as birds, easily crossed the land bridge, while others, like woolly rhinos (Coelodonta antiquitatis), didn’t make the migration. The land bridge, now submerged under the Bering Strait between Alaska and Russia, was above water from about 36,000 years ago to 11,000 years ago. Scientists thought it might have looked a lot like the grassy, arid steppe landscape in Siberia and Alaska at the time — but no one had ever investigated the ocean floor where the “bridge” once stood. Last year, researchers led by University of Alaska Fairbanks geologist Sarah Fowell set out on the research vessel Sikuliaq to extract cores of sediment from the floor of the Bering Sea. It was the first attempt to reconstruct the ancient landscape and climate of the land bridge. The researchers presented their results today (Dec. 10) at the annual meeting of the American Geophysical Union in Washington, D.C. Instead of a grassy steppe, they found a marshy landscape crisscrossed by rivers and dotted with little lakes. “We were looking for several large lakes,” Fowell said. “What we actually found was evidence of lots of small lakes and river channels.” Lake sediments were apparent in the ocean floor cores, as were pollen, small fossils, ancient DNA and organic matter. The pollen and fossils revealed that the landscape hosted trees and mosses. The researchers also found egg cases from water fleas (Daphnia), a freshwater crustacean. This marshy environment may have been particularly welcoming for some species such as birds, but there were also spots where there was evidence of larger mammals making the migration. One site hosted mammoth DNA. Bison are also known to have crossed from Eurasia to North America during the time that the land bridge existed, and horses are known to have made it from North America to Eurasia. “Even if it was mostly floodplains and ponds, the grazers were around, just uphill following higher, drier areas,” Fowell said. However, the environment may have been less conducive for species that did not make the move between continents, such as the woolly rhino (a Eurasian native), American camel (native to north and central America), and the short-faced bear (native to North America). “The watery, wet landscape could have been a barrier for some species,” said Jenna Hill, a geologist with the U.S. Geological Survey who is also presenting research on the Bering Sea core data at the AGU meeting, “or a pathway for species that actually travel by water.” Further research will be needed to understand the full impact of the environment on migration. Republished from an article by Stephanie Pappas in Live Science
Explore Lake Roosevelt National Recreation Area
The Lake Roosevelt National Recreation Area serves as a striking landmark that narrates a dramatic geological history shaped by colossal natural forces. Greatly influenced by the Missoula Floods, this area, part of the Ice Age Floods National Geologic Trail, reveals not only stunning landscapes but also insights into the Earth’s geological story. Understanding this region offers a glimpse into the powerful events that occurred between 13,500 and 18,500 years ago, as well as the enduring environmental significance of these features. Lake Roosevelt and Grand Coulee Dam Lake Roosevelt, created by the Grand Coulee Dam in the 1930s, serves multiple purposes: from water storage and hydroelectric power generation to recreation and wildlife preservation. The lake provides a crucial habitat for various species and supports a vibrant ecosystem and is home to a range of fish species, including walleye, rainbow trout, and Kokanee salmon. The surrounding lands offer habitats for birds and other wildlife, contributing to ecological balance. With over 400 miles of scenic shoreline, the 150 mile long goes from Grand Coulee nearly to the Canadian board and is a haven for outdoor enthusiasts. The lake offers expansive waters perfect for various forms of boating. Anglers can enjoy abundant fishing opportunities year-round. 32 different campgrounds such as Spring Canyon close to Grand Coulee, WA offer numerous places to extend your overnight stays with these stunning landscapes. Historical Heritage The Lake Roosevelt area holds historical significance for the Confederated Tribes of the Colville Reservation and the Spokane Tribe of Indians, highlighting the intertwined relationship between Native heritage and the natural landscape. The National Park Service (NPS) supports Bureau of Reclamation management of Bakes Lake, Coulee Dam, and Lake Roosevelt. NPS works with Washington State Parks throughout the Grand Coulee Corridor and along with the Tribes and Washington Department of Natural Resources, oversees recreation on the water and lands of Lake Roosevelt NRA. Our collective efforts work to ensure that these natural treasures are preserved for future generations. Visitors to the area can engage with a variety of programs and informational resources that enhance their understanding and respect for the environment. Power in Nature The Grand Coulee and Lake Roosevelt National Recreation Area stand as remarkable examples of nature’s power and the intricate tapestry of geological history. From the cataclysmic Missoula Floods that sculpted the landscape to the thriving ecosystems supported by Lake Roosevelt, this region offers an unparalleled opportunity for exploration and discovery. Whether you are an avid hiker, a passionate angler, or a curious geology enthusiast, this area provides not only recreational activities but also a deeper connection to the Earth’s history. As we delve into the breathtaking scenery and rich cultural heritage of this national recreation area, we are reminded of the dynamic forces that shape our world. The Grand Coulee and Lake Roosevelt invite each visitor to engage with the past while understanding the importance of stewardship for future generations. This stunning landscape not only captivates the eye; it expands our knowledge of nature and our place within Ice Age Floods National Geologic Trail.
Coyote Canyon Mammoth Dig
The Coyote Canyon Mammoth Dig is an active paleontological excavation site in the Horse Heaven Hills near Kennewick, Washington. It’s a significant project that sheds light on the history of the Ice Age floods in the Tri-Cities area. The dig focuses on the unearthed remains of a Columbian mammoth that lived approximately 17,500 years ago. The mammoth’s carcass was buried in Touchet beds, a geological formation laid down by ancient floods. The site sits at an elevation of 1040 feet above sea level, which is considerably higher than the current elevation of the Columbia River, which is only 350 feet above sea level about 7 miles north. Scientists estimate that Lake Lewis, a massive glacial lake that existed during the Ice Age, reached a maximum surface elevation of over 1200 feet above sea level at the time the mammoth perished. This substantial difference in elevation hints at the immense power of the Ice Age floods that swept across the region. Another fascinating aspect of the Coyote Canyon Mammoth Dig is the discovery of a vast pile of erratic rocks. Initially thought to be a small cluster, the collection of these displaced rocks has grown to extend into several adjacent dig units. A dig unit, for those unfamiliar with archaeological and paleontological fieldwork, is a standardized square measuring 2 meters by 2 meters that archaeologists and paleontologists use to meticulously excavate and collect data. The MCBones Research Center, a non-profit organization, spearheads the Coyote Canyon Mammoth Dig. They offer educational tours for schools and other groups, providing a firsthand look at this significant paleontological excavation. These tours are a great opportunity to learn more about the Ice Age floods, mammoths, and the meticulous work of paleontologists. For more information about the Coyote Canyon Mammoth Dig, including details about tours, visit the MCBones Research Center website at www.mcbones.org.
Volunteers Help Shape the IAFI!
We’re reaching out to ask for your help. As we work toward our mission of promoting public awareness and education about the Ice Age Floods, our chapters have been facing a significant challenge: a shortage of active member volunteers willing to step into leadership roles or assist with essential chapter functions. Many of our current leaders are in their 70s and 80s, and the demands of their roles are becoming challenging. While our dedicated leaders works to maintain our organization’s momentum, we need support to ensure our continued growth and success. Your involvement will be crucial in helping to: Organize events: Assist with planning field trips, chapter functions, and speaker series. Provide administrative support: Help with recordkeeping, website updates, and newsletter contributions. Engage with the community: Connect with local schools and media outlets to spread awareness about our mission. Contribute fresh perspectives: Share your ideas and expertise to help us adapt to a changing world. Here are some ways you can get involved: Volunteer for events: Help plan and execute field trips, workshops, and conferences. Join a committee: Contribute to our leadership team and help make important decisions. Share your expertise: Offer your skills in areas like marketing, communications, or technology. By becoming more involved, you can: Strengthen your chapter: Contribute your time and skills to make your local chapter more vibrant and effective. Share your knowledge: Bring new ideas and contemporary skills to our organization. Support the organization: Help IAFI achieve its goals and become the foremost provider of Ice Age Floods information. No matter your level of experience or commitment, we welcome your participation. Whether you can volunteer a few hours a month or are interested in taking on a leadership role, your involvement will make a significant difference. The involvement of many will lighten the load on the few, and also bring a much-needed infusion of energy and fresh perspectives. We believe that by working together, we can strengthen our organization and better serve our mission of promoting public awareness and education about the Ice Age Floods. Your participation is essential. To get involved, please contact your local chapter through the IAFI.org website
Bitterroot Valley Glacial Erratics
Two glacial erratics in the Bitterroot Valley, the Lone Rock School erratic and the Rome Lane erratic, were deposited during the last high stand of Lake Missoula about 13,000 years ago. Both these glacial erratics are easy to visit. At the extreme Southern end of the Bitterroot Valley is beautiful Lake Como named after its Italian alpine counter part by Father Ravalli a Jesuit Black Robe tasked with bringing literacy and Jesus to the native Salish people in 1845 via St Mary’s Mission in nearby Stevensville. Lake Como is a beautiful place for lunch and a hike/bike on the trail around lake including a beautiful waterfall a the head of the lake. Several mountain glaciers coalesced here and neighboring drainage to make the largest mass of ice calving into the lake south of the Flathead lobe of the Cordilleran ice sheet at Polson. This mass exited the mountains, floated into and calved into Glacial Lake Missoula. This was the primary iceberg generator for the Bitterroot Valley. As they floated out into the lake and melted they dropped large rocks called erratic onto the lake floor, which is now the surface of the valley. Lone Rock School Erratic The easiest one to find is the Lone Rock School erratic. From Stevensville, proceed north on the Eastside Highway, county road 269, to the junction with county road 268, turn right. Follow county road 268 until you reach the Lone Rock School on your left; the erratic is the large boulder in front of the south side of the school, and behind the fence (see map below). The Lone Rock School erratic is 69” tall, 58” wide, 85” long, and weighs in at about 8.5 metric tons or about 18,700 lbs. This large erratic is a type of granite called quartz monzonite. The minerals that make up this rock type are, in order of abundance, plagioclase (calcium and/or sodium rich) feldspar, orthoclase (potassium rich) feldspar, biotite (dark mica), and quartz. If you look closely you will see that the quartz typically stands out in relief with respect to the other minerals and that its surface has been polished to a smooth finish. This is the result of dense glacial ice grinding over the surface of the rock. Rome Lane Erratic The Rome Lane erratic measures 47” tall, 117” long, 96” wide, and weighs in at about 13 metric tons or about 28,600 lbs. The Rome Lane erratic is almost identical to the Lone Rock School erratic; it to is quartz monzonite granite with approximately the same minerals and mineral proportions. The observation that both erratics are of similar rock type suggests that they came from a similar source region. There are sources of quartz monzonite granite in both the Sapphire and Bitterroot Mountains, which is the source of these erratics? Since we know that the erratics were carried to the shores of glacial Lake Missoula by glaciers, we can rule out the Sapphires as a possible source because we know that no glaciers in the Sapphire Mountains ever reached the shores of Lake Missoula. So, the erratics had to come from the Bitterroot Mountains where the quartz monzonite granite lies anywhere between 5 and 20 miles from the ancient shoreline of Lake Missoula. That means glaciers carried the erratics for distances of up to 20 miles (32.2 km) before reaching the shores of glacial Lake Missoula. Which at an average velocity of 5 meters per day (normal for most valley glaciers with the exception of rare bursts in velocity up to 75 meters per day) would take about 18 years. Which Erratic is Oldest? The quartz grains on the surfaces of the Rome Lane erratic are polished to a smooth shine and stand out in relief above the other minerals, similar to the Lone Rock School erratic. However, the quartz grains exposed on the top surface of the Rome Lane erratic seem to exhibit higher relief than the quartz grains exposed on any other side of the Rome Lane erratic and/or the top surface of the Lone Rock School erratic. Why is this? Rainwater is slightly acidic and acidic fluids can break down some minerals, such as feldspar, and turn them into clay. Quartz, however, is very resistant to acidic fluids and as a result takes longer to break down or weather. It is this difference in weathering rates between feldspar and quartz that causes the quartz grains to stand higher than the feldspar grains. So, based on this relationship we can say that the greater the relief between quartz and feldspar on a rock surface, the longer that surface has been exposed to the elements i.e. rain and wind. With that in mind, which erratic’s top surface has been exposed longer? If you answered Lone Rock, you are correct. As it turns out the Lone Rock School erratic was dug up and moved from its original location, about ¾ of a mile to the south of where it sits today, to commemorate the Lone Rock Schools’ centennial in 1985, in fact upon its excavation portions of the erratic broke off and remain buried. So what is the top surface of the Lone Rock School erratic today may well not have been the top surface before 1985, and our mineral weathering hypothesis fits the facts.
Was the 1700 Cascadia earthquake one or many ruptures?
It’s generally accepted that a massive Cascadia earthquake occurred along the British Columbia-Washington-Oregon-N. California coast on January 26, 1700. The earthquake was a result of a rupture of the plate boundary between the North American plate overriding and subducting the Juan de Fuca plate. The evidence for the magnitude and precise timing of the quake includes tsunami deposits and dendrochronology dating at many places along that coastline, and records of a “ghost” tsunami at several locations in Japan. In a Sept. 24, 2024 presentation for Central Oregon Geoscience Society, Diego Melgar of University of Oregon explained earthquake modeling that is seeking to match the earthquake evidence. It turns out there may be millions of possible scenarios where an initial 8.1 to 9.2 magnitude quake followed by up to 5 lesser magnitude aftershocks up to months later could potentially fit the data. That’s not really good news for the Cascadia region, because multiple giant quakes would be no less hazardous than one enormous one. The geological history of the Cascadia subduction zones suggests that it experiences very large earthquakes every few centuries (between every 240 years and every 500 years). The question now is whether these temblors always occur as a single huge earthquake or if sometimes they’re a series of very big ones. Better understanding the nature of the earthquake(s) is important for estimating future tsunami hazards and for developing building codes, disaster response plans, and other critical earthquake-dependent planning. Diego expects continued modeling that considers data from turbidites and tsunami deposit thicknesses may help narrow the possible scenarios, but he stresses that even an 8.1 magnitude quake can be quite devastating. “The tsunami might not be as large from an 8.1, but the shaking can be really intense,” Melgar said. “It’s just dangerous in a different way. Indeed, a decade in which giant quakes hit every two or three years might even be more devastating to people living in the region than a single quake hitting every few hundred years. That’s why it’s important to get to the bottom of which scenario is more likely.” View the recording of Diego’s presentation here or read the “Was a humongous Cascadia earthquake just one of many?” article in Live Science by Stephanie Pappas here.