I watched this in its entirety. Great work, thank God those of us that are interested in the topic from home have guys like Shawn.

This is exactly what I've been looking for. For over 20 years I've wanted to know this exact information about the Bonneville Flood. Thank you, from the bottom of my heart, for presenting this.

Still watching but have to say Shawn is the only person (in my You Tube world) who gives detailed attention to the Bonneville flood. Always glad to see the presentations. Thanks to Shawn and the group.

Not sure why KZfaq suggested this to me today, but Holy Cow, man! 1.33 hours of enthrallment right here! I'm a Utah native. I have learned about Lake Bonneville all through primary school, we ride our bikes along multiple parts of the Bonneville Shoreline Trail, I have wondered out loud why the Bear River flows where it does, but never dived deeper. Now I'm droning on and on to my wife and two boys and currently I'm just like, "look, just watch the presentation, okay?" The only drawback is that now we'll have some weekend road trips to really otherwise boring places... Thanks, mate!

Great update on the previous Lake Bonneville video, which I totally enjoyed also. The Google Earth and drone views showed so clearly what you were describing--a sort of mini-field trip! My favorite part was Devils Corral, where your usual excellent description made it easy to see and understand the sheer force of the flood waters. The boulder bars were also eye-openers. Thank you for once again helping us armchair geologists continue our education!

Your talk sure brought Lake Bonneville into clearer focus. Impressive. Thank you !

Excellent presentation! Thanks, Professor!

I enjoy flying from south to north, watching the flood stories unfold beneath me from Utah to Washington. I agree with you that the Bonneville flood deserves much more exposure, and appreciate greatly that you have helped with that here! A remarkable and ever unfolding tale!

So excited about this upload! Thank you!

You can support my lecture and field videos by clicking on the "Thanks" button just above (right of Like button) or by going here: www.paypal.com/donate/?hosted_button_id=EWUSLG3GBS5W8

Please write that book Shawn. I would buy it. I own your other 2 books . Thanks for this lecture.

I love your channel! The algorithm gave me your other “short version” first, and then I watched this one. This one is so much better! Thanks!

This is a really good presentation! As I have mentioned this spring I've been studying the floods through WA state. Nick has been doing a lot on KZfaq on them. His geology 351 class topic spring quarter was ice age floods. But he did cover the Bonneville Flood too. There are locations in WA that show evidence of the Bonneville. Your videos that I watched during the last winter had prepared me for the WA portion information. I have been working on reading more about the Bonneville Flood. This presentation has helped me greatly to create a mental timeline of the events. Your maps also helped me with locations in southern Idaho. I have personal history with Massacre Rocks. I saw it on the map. Did erosion from Bonneville cause those rocks to be standing alone in that flood plain? Yes Missoula floods are exciting and dramatic. But to me the Bonneville Flood is dramatic because it was so big for a much further distance and longer time period. I hope you will do more presentations, you are very good at it. They make a good overview of a topic. Your short videos are information packed and very personal with each viewer. The shorter videos cover specific features so well. Combining your presentations with the short ones makes a course complete on the specific topics. Thank you very much.

Excellent Shawn, I remember your first KZfaq video on it, that’s what brought me to the channel couple years ago, enjoyed everything you’ve done

We used to travel from Corvallis to Cache Valley every year to visit grandparents. I was always memorized by the benchmarks and spent many hours contemplating Lake Bonneville...and the petrified watermelons. Never connected the two things.

Shawn, what you see as a dearth of educational material on the Bonneville flood, I see as a golden opportunity for you to write a book - the first book? - on the Bonneville event. If you do a good enough job, it may become the definitive book on the subject.

1:00:00 The question about the east had me thinking of Glacial Lake Agassiz. A little search indicated that Lake Agassiz had many incarnations as the Laurentian Ice Sheet retreated. The only flood-- and it was a doozy-- referred to associated with this lake was through current day Alberta, into the North West Territories and down the Mackenzie River valley into the Arctic. So, I would suppose that would qualify it as a "Western" flood. However, the last incarnation of Glacial Lake Agassiz drained via the Ottawa River valley and into the St. Lawrence. While that was a very significant event, I think we start to get into a philosophical debate about what constitutes a "flood". While the flow was on a massive scale, it might not have been as suddenly catastrophic as the Bonneville flood and the near by flood which shall not be named.

Love these lectures, top quality stuff, would be great to see more! Thanks for sharing!

9 Feb 2024......While waiting for the update on Iceland I watched most the Nick Zentner joint venture with you. I pulled up your presentation of The Bonneville Flood and watched it on my 2nd screen beside your visit with Nick. Thanks, Shawn, for sharing your knowledge with us!

Just finished watching this I am a Zentnerd So now am Watching and listening and learning from you as well

Man i was expecting a you tube presentation not a college lecture 😮 im very happy i have this playing on the speakers in the van as we travel

Very well done Shawn!!

Excellent presentation. I found this talk very interesting because my wife and I are planning to go to the area in August. I can't wait to see the flood evidence for myself. It should be a lot of fun.

As a Buhl Idaho resident Shawn's presentation of our great state is nothing more than amazing, like ti shake his hand one day

Great review….excellent presentation! 👍

Fantastic presentation. Such a beautiful place!

Great lecture and I hope to see this part of the country. You deserve a KZfaq following like Nick Zentner.

Fascinating! A great talk and very timely -- I just got off the John Day river a few days ago -- the guides talked about the un-named other flood quite a bit. I had never heard of that one, but I brought up the Bonneville flood, as I've visited the Twin Falls area. I was delighted to find this video about it when I returned home. Thank you, Shawn!!

Thank you very much Shawn 🫡

Great talk!

Excellent, thank you!

This is brilliant wow mind blown a huge amount of water

I grew up in Soda Springs now in SLC I had no idea that the B. River changed course here and headed south. Amazing. I always loved geology. Wanted to do it as a career. I admire your work. Thank you for the education.

Just purchased both books

This talk had me rivetted -- missed my breakfast totally !! Well worth it 🏆

Fascinating!

Thanks!

Go Bonneville Flood! 😊 Really interesting, followed along on Google maps. What a beautiful part of the world with awesome features nature has created.

What a great and informative talk!

Very good and interesting presentation.

Love it! Please do more!

Awesome. Answered my questions and generated more. Thank you!

This was amazing

Incredible presentation! Thank you.

Thank you for the Idaho/Utah side fits in to Bonneville side .

This was super interesting! Going to subscribe to his channel, too. Thanks for sharing this.

I'm curious-since the Gilbert Episode apparently occurred about the same time as the glaciers to the north started melting away, is it possible that the rise in Lake Bonnevile was a pluvial phenomenon? Due to the overall increase in atmospheric humidity, the melting glaciers would've likely increased rain effects and added to precipitation events during this time.

This is awesome! Sometimes I wish I had chosen Geology as a career!

I agree, we need more attention to all aspects of lake bonneville

Very cool

Interesting .. .made me think of how the Zambezi erodes the granite bedrock back, exploiting fissures and cracks ie Victoria Falls

The part at 41:35 legitimately made me jump out of my seat lol Great presentation. I would love to attend a public lecture some day.

I’ll be exploring these two floods probably my whole life

Great work and wonderfully presented, thank you

I was exploring Salt Lake area and I was really curious where did all that water go to form the desert. Quick search and I end up here, a video published 7 days ago. Should I search it a week ago - I would not be able to find much. Such a fascinating geological event, a pretty damn significant one - unbelievable there’s not a documentary about it yet.

41:35 This has to be the most valuable insight in this video.

Interesting. I ❤️ geology.

Excellent presentation Professor. Very educational, and You gave me an answer to a question regarding the sequence of the Bonneville and Missoula floods. Thank you sir - and thank you for bringing your expertise to KZfaq for the benefit of untold numbers of us who share your interest in geology!

Much of my childhood was spent on the ancient shoreline of Lake Bonneville in Sandy Utah. It's called Sandy because there is, of course, a vast amount of sand from the lake. Where I live now would be about 800 feet deep when the lake level was at its maximum depth.

Watching as a primer for the Zentner-Willsey broadcast tomorrow……and glad I did!

Im about to graduate from utah state university as a geology major. We know all about Bonneville due to evidence visible in Logan, with campus even residing on the Provo delta of the shoreline. Being an interpreter to give this kind of history in a national or state park is my dream. Now shorten the lecture to 5 minutes, thats what I want to do as a career. Well done

This lecture helped reinforce the presentation you did for Nick Zentner . Thanks! 🙂

I was just there for the first time. Incredible place to visit.

Thanks for another interesting explanatory voyage. I've admired the old poised lakeshores of the UT West Desert for decades, obviously something huge was and then wasn't-

I really enjoy your vids.

I went caving in some lava tubes out that way about thirty years ago. It's wild to be deep underground and consider that the earth under your feet was once a vast plain open to the sky. It absolutely boggles the mind how much landmass volcanism actually produces. With a thousand cubic miles of magma in the chamber I can't even imagine how terrible and widespread the devastation would be if the Yellowstone Caldera suddenly erupted in all its ancient fury. As impressive and awe-inspiring as the Bonneville Flood must have been to see, it pales in comparison to the forces of nature that shaped the land beneath it.

Just excellent. Content and delivery were fantastic.

I live and drive thousands of miles a year for work through the area of the "Flood that shall not be named". I've also been through Red Rock Pass and stopped there for an hour and did some sight seeing. I have all those Missoula Floods books you showed and then some. Maybe it's time for a geologist to write a book on the Lake Bonneville Flood, hint, hint. My teenage daughter wants to go to Thousand Springs State Park this summer, need to find your video on it and send it to her. Last summer we did the MT Dinosaur Trail for our vacation. Love your videos and keep up your good work.

Thanks for telling us about this flood! I had never heard about it, even though I live in California. I guess, in Southern California, we are less concerned with big floods like this and we know much more about flash floods. I used to go down to the wash to watch the flash floods when I was a kid but I made sure to stay up the hill to watch it because there was a scary amount of fast flowing water going down the wash. They've since fixed it so that it doesn't even rise that much during heavy rain storms.

At 44:17 I found that exact view on google maps. You go to 3D and then orient to the West. It's nice to be able to look around at Google Earth and see what you are talking about.....Maybe you could use that more.....Thanks..Great presentation. I love seeing things about the earth and geology. So much more is left to be learned.

Shawn: There are many more catastrophic floods: Fraser River, Lake Athabasca; Lake Michigan over topped and carved out the Illinois River Valley, recent smaller floods in Iceland, English Channel, Mediterranean and Black Sea.

I knew it! Shawn went to NAU and so did I! Go Lumberjacks!

Thanks so much for you presentation. Having lived in Salt Lake City pretty much all my life,(73. Years) this has been the very first time through your wonderful graphics and great presentation I’ve really understood what and how the huge prehistoric lake leaked out into the Columbia River and left the now salt lake that this area is named for. Thank you so much for filling in the gaps in my knowledge!😊😊😊😊 1:19:50

I subscribed. Please surf up Rick Sneddon's 3 part series on the well supported Big quake along the Wasatch Fault and the evidence of the Tsunami that accompanied it. It is arguably the single point in time starting the flood.

I first heard of this event through a Randal Carlson presentation, I certainly enjoyed this and your clay caves presentation.

I sure hope lower educational schools of today teach this, they certainly didn't back in the late 50's or early 60's. At 75 years of age, I have never heard of the Bonneville Flood. My only knowledge was the Bonneville Salt Flats for speed records. That was a big thing back then for teenage boys. What a shame. Great presentation. By the way Shawn, I have placed both of your books in my Amazon buy list for next months funny money payment.

It's funny that when I was in college in the 90s the Missoula flood was still pretty controversial. Now it's the famous cousin, haha. I was at a rest stop in Utah this summer and saw a fantastic educational display about the Bonneville flood, which sent me down a new rabbit hole. Great video, thanks for posting.

Superb lecture. I was introduced to (the geologic expression of) Bonneville Lake at Antelope Island. And, lucky me, will be heading up to Boise. This lecture-its content, illustrations, and presentation-is a perfect way to take on this territory, explore the evidence all along the way, and gain insight in to one of the most catastrophic events in the Anthropocene. Thank you very much.

I think of the Bonneville flood as having been triggered by a huge spring runoff during the Ice Age, or maybe more likely a massive wind seiche causing ice to plow through the loose sediments of the previous stable overflow channel.

Interesting fact; the bear river is the largest river in north America to not reach an ocean.

I think what’s cool is that people were living is the northwest already at that time.

Regarding the timeframe of the Missoula floods versus the Bonneville flood Nick Zentner is doing a geological series revisiting/adding some details to the Missoula floods. I'm not fully caught up on the series but one of the big takeaways is that the Missoula floods have older chapters including at least some reliefs which show pre Wisconsin glaciation episodes as overlying layers of calcrete soil horizons cap megaflood slack water deposits. The consequence of these findings is that the amount of eroded rock now gets split up by even more flood events and thus the floods might not have been as extreme as they would have to be to carve all of the coulees during the Wisconsin glaciation. At the very least it seems that the Grande Coulee was probably already largely carved out before the Wisconsin glaciation began. And there was a picture which shows the distinctive Bonneville flood deposit interbedded between both older and younger Missoula flood deposits. I couldn't help but note that Missoula slack waters carried far less larger rocks compared to the Bonneville slack water layer at lake Lewis. From Nick Zentner's A to Z series I do remember hearing about floods associated with the Hudson waterway system as well as floods in the Mississippi river system flowing out from the Laurentide ice sheet but that they aren't as dramatic/sexy since the rock types involved weren't as readily eroded to create such dramatic landscapes. Check out his livestream A to Z series. The guy asking about the salt seemed to me like he might have been mistaken in thinking the entire lake drained which would have removed the whole salt hopefully your clarification on the Provo shoreline resolved their confusion. In terms of the Snake River plain the seismic tomography images I've seen of the upper mantle beneath the western US Nick Zentner's A to Z series for the Eocene and Baja BC I can't help but note that the slow sheer velocity zone in the upper mantle below the snake river plain connects directly to the Juan de Fuca ridge via a zig zagging path through south eastern Oregon and northern California while on the other side it joins up with the Yellowstone Hotspot in what looks like an oceanic triple Junction the border of eastern North America and the Colorado plateau the Rio Grande rift valley and then darting through New Mexico and Arizona where it joins up with the East Pacific Rise beneath the Sea of Cortez/Gulf of California. In that sense the mysterious volcanism just outside the Snake river plain, and continued activity of the snake river plain is probably the effects of the underlying mantle. Fascinating if poorly understood stuff but the picture looks to be more complicated. (The timing of the onset of the Tertiary Ignimbrite flare up and the exposed metamorphic core complexes discussed in the crazy Eocene series certainly fits with the picture where the upper mantle and oceanic crust are interconnected with only really phase transformation differences in the absence of an overlying continent. Fascinating research stuff.

Awesomeness! Thanks for this presentation Shawn, might be time to write that book? I'd sure like to see some CGI simulations of this event; maybe the AI can take care of that for us if you feed it all this great info.

Thank you for this great video, it's the best primer on the Bonneville flood on KZfaq. For me, the Missoula floods overshadowed the Bonneville simply because of how frequent they were, but the Bonneville's monstrous scale is mindblowing. In a way, it's too bad the Bonneville flood followed most of the Snake River drainage to the sea, instead of punching huge coulees out of basalt.

thanks for the lesson; one recommendation would be to install or configure a mouse pointer highlighter.. Windows has a few defaults or you can get one specific for screen sharing stuff. Kinda hard to see/find your mouse when you're using it to point things out

I have been looking for a good presentation on lake boniville. What i took away on the 3 causes of the breach was probably saturation of the aluvium combind with a seismic event causing liquefaction and the flow of the deposits of alluvial landscape. So it could have emptied much faster than a few weeks.

Man i miss this content

Very interesting to this amateur Arizona geologist; thank you! And it must be noted that you can't go wrong with a degree in geology, archeology or anthropology from NAU, ASU or UA. ;-)

As a young kid in the mountains of southern Idaho.... I found it odd even then to find seashells in the mountain dirt. I only recently found out why.

The flood waters flowed over much of the northside and entered the Malad river gorge north of the interstate southwest of Gooding. That's why there is a shortage of top soil over much of the northside.

Magnificent, Prof. Willsey! First time I've seen, for example, a comparison between those two great floods. Could either or both of them occur again? -- charles johnson, sacramento ca

Great presentation! Did Shoshone Falls form during the flood or did it predate the flood? Thanks! Just discovered your videos - great stuff!

Thank you Shawn. I too was raised on Air Force Bases the last one being Mtn Home AFB where we moved in 1970. I patronized Stinker Stations back in the time they were still operating and their advertising signs were legendary. Thanks for showcasing this particular one. I spent three years (disjointed) in eastern Idaho so I became aware of Red Rock Pass then. I learned more here from you than ever. Is the source for the water for the Bonneville event glacial? Bretz speaks of old ice sheet influence in the flood events in Washington. Could the water be from this source?

Locals don't refer to it as the Pocatello Gap or Pocatello Narrows. Though it very well could be. They call it the "Portneuf Gap". Stinker Gas Stations still exist.

41:36 made me jump 😂

The Rodney Dangerfield of prehistoric geologic events.

Yes, this is better than your 20 minute Bonneville flood video. My question: where did the water come from that made Bear River such a huge river? Just draining Uintah and Wasatch Mountains?

Since your prior Bonneville Flood videos I've wondered what would have happened had the Bear River not been diverted southward. No flood and a much larger Great Salt Lake remnant?

For anyone wondering how peak flow of Shoshone Falls compares to the Bonneville Flood (I did after staring at that picture of it), Bonneville was about 3,000 times more massive.

Re an earthquake trigger, liquefaction: if the soil/rock material that is acting as a dam for Lake Bonneville has a groundwater layer, this subsurface layer will effectively liquefy during earthquake shaking, due to the temporary compaction of the overriding soil/rock layers thereby causing an increase in pore water pressure in the groundwater containing layer. This can cause catastrophic loss of soil strength during earthquakes - earthquake engineers can tell you all about the liquefaction phenomena.