The big mystery of the Sawtooth Mountains of Idaho and their impressive glacial features

Here's a riddle. Two mountain ranges in Idaho lie within 60 miles of each other. The highest peaks in Mountain Range A are about 9,000 to 10,000 feet above sea level. Mountain Range B has many peaks over 11,000 feet and several that exceed 12,000 feet above sea level. Both mountain ranges hosted glaciers during the Pleistocene Ice Age. Mountain Range A shows abundant evidence of extensive glacial erosion; the glaciers were big here and existed on both the east and west sides of the range. Mountain Range B was far less glaciated, with smaller glaciers mainly confined to the eastern side of the range.
Why would a smaller mountain range have much larger glaciers than a taller range? Team up with geology professor Shawn Willsey as he explores that question atop a scenic hill overlooking the Stanley basin near the iconic Sawtooth mountains in central Idaho.
Approximate GPS location: 44.15657, -114.87128
I love doing these videos and will continue to do so but if you want to provide support or much appreciated gas money, you can send support via:
Venmo @Shawn-Willsey (be sure to put two L's in last name)
or PayPal: www.paypal.com/donate/?hosted...
or a good ol' fashioned check to this address:
Shawn Willsey
College of Southern Idaho
315 Falls Avenue
Twin Falls, ID 83303

[@dougewing1571]

I've been to Idaho once back in 1982, should of stayed there. Awesome country for sure.....

[@Hossak]

That is just spectacular scenery! Really beautiful. Thanks for the great video!

[@deanwalker6262]

Thank you, I absolutely love this kind of video. What beautiful footage of the range. The Sawtooths are one of the few last areas of the contiguous US I haven’t been to yet. I’ve once read Lewis/Clark said areas of Idaho were the most impressive and beautiful places along their journey. Again thank you.

[@shawnwillsey]

It really could be a national park.

[@andrewpassow2712]

Awesome presentation, Shawn. You positioned yourself in a pivotal spot to accurately describe the 'topography'. What a gorgeous day to be out in the field teaching. Awesome demonstration and choice vocabulary . . . 'stryration', etc. (spell check)

[@ogarcia515]

Interesting. Spanish for "saw," like a saw to cut wood, is "Sierra." So the Sierra mountains are also named for a saw.

[@Ruger44Redhawk]

After moving from Missouri to Oregon back in the summer of 2004 and then making the summit of Mt. St. Helens in July of 2004 right before she blew again (and subsequently closed until 2007), I became enamored with geology. Being in the Volcanic Arc of the Cascade Mountains we relentlessly explored and completed a lot of those summits (Mt. St. Helens, Mt. Hood, Mt. Adams, Mt. Jefferson, South Sister). The lava fields around Sisters and Bend and some around Mt. Adams are an awesome sight. Now that we live in Idaho, I am even more interested with the geology of the Blue Mountains in Eastern Oregon and especially the Wallowa Mountains (which I consider part of the Blue Mountains). In addition, Hell's Canyon and the Snake River that carved the deepest gorge in the country on the Idaho/Oregon border and the Seven Devils Mountains in Idaho looming over it. There is so much to explore in Idaho, Wyoming and Montana. Being close to the Owyhees, I love getting lost up in there where nobody goes and finding all those rock formations and gorges. I do need to check out the Crater's of the Moon and City of Rocks and backpack into the Bighorn Crags as well as complete the summits of the 12,000' peaks in the Lemhi and Lost River Range. Might as well throw the Grand Teton in there. So much to do, so little time!

[@bobbyadkins885]

Great video, I’m always amazed by how much beauty there is in the western US, being someone back east of the Mississippi we really never know or appreciate the beauty and geology of states like Idaho, Wyoming, Washington etc

[@BlGGESTBROTHER]

Awesome! Another great video 👍

[@toughenupfluffy7294]

Holy mackerel! That was amazing! That's the biggest end moraine I've ever seen! I'm a Colorado native, and this makes me want to reassess the landscapes I thought I knew from birth. Glacial topography is incredible, to think how much ice and gravity can do!

[@rj-zz8im]

So glad I came crossed your channel. Besides this fascinating information, the view is amazing. I couldn't imagine seeing that every single day. Spectacular.

[@shawnwillsey]

Welcome aboard and glad you like the content.

[@marinangeli3250]

Great job, Shawn! I can just never get enough of the Sawtooths but have not been able to spend any time in them since the Total Solar Eclipse of 2017, which I had the enormous privilege of viewing from a ledge overlooking Lake 9000, at the base of Thompson Peak. At 62 and very out of shape, the hike up along the moraine, that Little Redfish Lake sits at the base of, was thankfully fairly gentle... until I got to the flank of Williams Peak. I look forward to more time in those cherished mountains sometime soon but, in the meantime, your videos on them are a true joy!

[@shawnwillsey]

Glad you could see them in person and revisit them with me.

[@marinangeli3250]

@@shawnwillsey My first introduction to the Sawtooths was in 1971, when I was 16. Spent well over 24 hours on a Greyhound bus from Bakersfield, to Vegas, to Salt Lake City, to Twin Falls, on my way to Stanley, where my mom and her new husband were living. As I crossed so much desert along the way, I began to wonder about this alpine paradise my parents promised. Leaving Twin Falls on a commuter style van that was part of the old Sun Valley Stages, crossing the Snake River Plain to Shoshone and points north, I REALLY started getting concerned... where was this alpine paradise? Were they just yanking my chain? Even after arriving in Ketchum, in front of the Casino Club, I still was not convinced that I was headed into a forested region. The drive from Ketchum to Galena Summit , to Smiley Creek, to Obsidian, to Stanley and, ultimately a little RV Park called Howdyville, near Stanley Lake, changed all that. My first hike into the Sawtooths, in 1971, was on foot from Howdyville (now Elk Mountain), to Iron Creek and Alpine Lake. I have covered lots of ground since then, lived in Stanley a few times over the years and, have never been able to shake the Sawtooths from my soul... and never wanted to. It's only the complexities of life as a senior citizen that currently keeps me from those beloved peaks... but not for long. When it comes to the Sawtooths... once bitten, forever smitten. Again, thank you Shawn, for sharing your Sawtooth travels! :)

[@shawnwillsey]

@@marinangeli3250 Wow, what a great story. Idaho has so much diversity in geology and scenery.

[@marinangeli3250]

@@shawnwillsey Yes, indeed. Geology + exquisite scenery... what could be better? Are you familiar with the Crystal Cave (now collapsed), not far from Monte Verita, in the Sawtooths? Somewhere in my collection is a smoky quartz crystal from it, given to me in the mid 1970s. At well over an inch in diameter, it is but a tiny specimen from a cave that yielded crystals 3 feet, and more, in length. Visiting the remains of the cave is on my bucket list, hopefully before I hit 70 :) Thanks again, for all you share!

[@AvanaVana]

Ah, the Stanley Basin! Galena Summit and the Stanley Basin are at the top of my list to visit in Idaho. You know what’s really interesting, regarding Pleistocene climate in this area, is that the great Lake Idaho that existed during the Pliocene had already dried up, and the climate and vegetation wasn’t altogether too different than today. However there seem to have been more lowland conifers (probably sucking up all the rich soils left by Lake Idaho). The reason I’m talking about Lake Idaho of course is the existence of a lake implies greatly enhanced moisture in the climate system, and lake-effect snow, in the Sawtooths north of it. But unlike the Great Basin, which hosted numerous gigantic lakes during the Pleistocene, Idaho really dried up in the Pleistocene, probably because it was in the “glacial steppe” ahead of the continental glaciers. However, basaltic lava eruptions in the region created lava dams that repeatedly blocked the Snake River and caused American Falls Lake (not the modern one!) to form, as a transient feature, which was eventually drained repeatedly as the river cut through the dams. This has me wondering if American Falls Lake existed long enough to locally cause more snowfall in the Sawtooths, via the lake-effect, which might partially account for its glacial buzzsaw. PS, last year (Feb 11, 2021) the USGS (well, the US Board on Geographic Names) officially recognized Idaho’s only glacier, a tiny thing under the north face of Mt. Borah! Btw, did you ever watch that old 1989 episode of Outdoor Idaho (IdahoPTV) where they climb Mt Borah with pack llamas? (In addition to Cajun cooking and falconry)

[@shawnwillsey]

Great thoughts here, Avana. I don't think the presence of Lake Idaho would have had much effect on the Sawtooths. Lake Idaho occupied the Western Snake River Plain, more or less due south and over several large ranges from the Sawtooths. In the winter, the prevailing wind direction is from the northwest so this doesn't set up well for a lake effect snow in the Sawtooths. Plus as I mentioned the Boise, Boulder, and Solidier Mountains were between the Sawtooths and lake. Fun stuff to think about though. I have seen the old Outdoor Idaho episode. The Borah "glacier" only has ice (if it still does) beneath the surface, in the talus, so technically its a rock glacier rather than a true glacier. That's my understanding.

[@AvanaVana]

@@shawnwillsey Ok, that makes sense. Although do we know the prevailing wind during stadial periods? The presence of the continental ice sheet would probably generate katabatic winds that still flow from a northerly direction. Still, it just intuitively feels like the presence of so many pluvial lakes in the Intermontane West during Pleistocene stadials implies increased moisture that might have something to do with it, even without a lake effect, just an orographic effect combined with higher regional moisture and a differently positioned jet stream. Not sure, but maybe something to look into beyond intuition. The fact that Lake Idaho dried up due to climatic changes, probably due to proximity to the proglacial steppe, throws a monkey wrench into any ideas about increased moisture, however. Re: Borah Peak’s “Otto Glacier”, see if you can track down the 2015 research paper by Joshua Keeley and Mathew Warbritton called “The Otto Glacier on Borah Peak, Lost River Range, Custer County, Idaho: Reconnaissance Survey Finds Further Evidence for Active Glacier”. They write: “Our survey confirmed the continued presence of the perennial ice mass originally identified in 1974, and concluded that the ice mass is indeed a glacier that continues to move under its own weight, based on measurements described herein in conjunction with results from the initial investigations in the 1970’s. The glacier is classified as a semi-covered clean-ice glacier based on the thin surficial cover of rock debris over two-thirds of the glacier's extent.” As a result of this study, Idaho’s CBS2 reports that in early February 2021, the Salmon-Challis National Forest organization met with the U.S. Board of Geographic Names and they officially approved its designation as “Otto Glacier”, as Idaho’s only active glacier.

[@shawnwillsey]

@@AvanaVana Yes, I am assuming similar weather and wind conditions to today but latitude is perhaps the most dominant factor. This part of Idaho lies in the westerlies where west winds dominate. In fact, these conditions are what allows Yellowstone to get so much precipitation today. Storms from the west in the winter track up the SRP and rise as they reach the Yellowstone Plateau. The lack of mountains in the SRP allows storms to retain most of their moisture and drop a large amount on Yellowstone. This is why it harbored a large ice cap during the Pleistocene. All that being said, someone smarter than I would need to address your comment about katabatic winds. More Borah Peak glacial madness. I can't remember if I read the article you mentioned. I did some research on the issue when working on Roadside Geology of Idaho and remember finding info counter to the conclusion of it being a legit glacier. The details are a bit foggy in my brain as I write this from a hotel room in Wenatchee, WA but I think co-author Paul Link and I agreed that the glacier was pretty much gone and even if it was still there, that it would likely be gone quite quickly given the recent climate trends. All semantics I suppose. I do remember the official name and designation announcement which I thought was somewhat humorous given that the glacier is likely on its last legs.

[@AvanaVana]

@@shawnwillsey Yes, it is completely ridiculous, I agree. But policymakers are desperate for 'good' climate news. Re: latitude of Sawtooths-isn't the Lost River Range at about the same latitude? Is it just that the Sawtooths created an orographic effect and all the snow was dumped on them, leaving the Lost River Range relatively unglaciated?

[@shawnwillsey]

@@AvanaVana Yes, Sawtooths, White Clouds and LRR are pretty much same latitude. Essentially, the Sawtooths get the lion's share of the precip from storms arriving from the W/NW and the LRR lie in their rainshadow. Less snow = smaller glaciers.

[@Danika_Nadzan]

Great video! I'm new to the Sawtooth Range and much of Idaho's geology. It is sure is beautiful country, and even more interesting when I hear how the topography was effectively sculpted by the glaciers. Thanks, Shawn, I learn so much from your videos!

[@shawnwillsey]

Thanks for watching. I appreciate it.

[@AKUSUXs]

I've been to the Stanley Basin, Redfish, Alturas, and so many more places in the area. I never seen this area from your perspective and it is impressive! Thank you.

[@hunt4redoctober628]

I had no idea that Idaho had such high mountains. Being in the UK, believe me the Sawtooth Range is spectacular compared to what we have. Great video again!

[@shawnwillsey]

Yep. Borah Peak is 12,662 feet above sea level and lies in the Lost River Range just east of here.

[@DontUputThatEvilOnMe]

Yes Idaho is like the low key Colorado that no one has ever heard of. Idahoans like it that way. Keeps the crowds away.

[@Ruger44Redhawk]

I believe (correct me if I'm wrong) Idaho has more 10,000' peaks than any other state. Which means peaks between 10, 000' and 13,000. At least that's what I read in the map room at the Bureau of Land Management here.

[@goldenratio5117]

If Idaho was rolled flat it would be close to the size of Oregon. Sawtooth mtns were called "Giants house" by the western Shoshone tribe because of the cannibalistic Giants that lived there. Which I believe to be true 100%.

[@davidk7324]

Fantastic video. Food for thought the next time I go back.

[@whitby910]

Thank you. All adding to my new knowledge of your wonderful country.

[@Mistydazzle]

Thank you! This is really reminding me of the scenario of the Collegiate Peaks in the Sawatch Mountain Range of the Colorado Rockies. Stunning, rugged, cirque carved mountains. The Arkansas River substitutes for the Salmon River. There are remnant lakes between moraines & evidence of vast lakes once filling the long north-south valley, east of the range. Once moraine dams were breached, water flowed into the Arkansas River, on its long journey to the Gulf of Mexico.

[@georgesheffield1580]

Or the Sandra de Christos . Further to the south

[@stevew5212]

cool. thanks Shawn

[@Will-Parr]

Excellent presentation. Congrats

[@TheKrisg50]

Awesome. Safe travels…..

[@dunnkruger8825]

Nice Thanks

[@edstud1]

I love the Sawtooth mountains! Love Redfish lake!

[@billrey8221]

Great job Shawn! I wonder how much snow and weight, had accumulated on those mountains 20, 30, 40, 50, thousand years ago. Even Yosemite has "U" shaped valleys and moraines. Amazing stuff!! Thanks for posting!

[@jdp0359]

What a beautiful part of the world!

[@carygrant8796]

I’ve flown along the Sawtooths and I think they are as scenic if not more than the Tetons.

[@shawnwillsey]

Agreed

[@3xHermes]

Wish I was moving to Idaho!

[@markrenton1093]

I would LOVE to move to Idaho.

[@ericclayton6287]

What is the relationship between the Owyhee pluton near Silver City and the sawtooth/Idaho batholith? I’ve heard they’re the same granite but they’re separated by that beautiful graben which to me looks like a secondary extension of the Snake River Plain. I’ve heard that they’ve recently found remnants of a large resurgent style caldera on the Oregon side of the Graben. Might be a good subject for a future video.

[@shawnwillsey]

Owyhee granite is Cretaceous in age, older than Sawtooth granite but the same age and composition as the Idaho batholith. Faults that border the Western Snake River Plain isolated the Owyhees (and pushed them up) and their granites.

[@leemaples1806]

Over the ridge and across the lake to the sawtooth mountain looks like its quite a distance.Some odd number of miles? Gorgeous scenery there.

[@AvanaVana]

The Stanley Basin on average is just a few miles in width, but some ~30 miles in length. From the edge of Redfish Lake to the other side of the valley is only like ~2 miles, but I don’t think Shawn was positioned directly opposite to it, I think probably more to then north, closer to Stanley (please correct me if I’m wrong, Shawn!)

[@marinangeli3250]

@@AvanaVana Yes, just a tiny bit north, at Boundary Creek, but pretty much due east of Thompson and Williams Peaks. Stanley is about another 5 miles north/north west. if your schedule permits, they are hosting a music festival next weekend... great way to visit the Stanley Basin and the Sawtooths and enjoy some fine music :)

[@keviny1936]

Has any paleo magnetic work been done on the Sawtooths? There may be evidence that the granite in the North Cascades of Washington State formed much farther south (Mexico) and traveled north to its present location. Also, at what depth did the granite of the Sawthooths form? Current thinking is that the Mt. Stuart batholith formed many kilometers below the surface and rose up to the surface as the crust was stretched westward in the Eocene.

[@BotanyJess]

Glaciation is nevertheless massive in the LRR. Stand at the headwall of Mount Breitenbach, at the shallow tarns below Mt. Church.. at Bear Creek Lake or the headwater cirques of Christian Gulch and tell me the glaciers in the LRR were small, lol. Ok ok. "Smaller" than in the Sawtooth Mts. Splitting hairs perhaps on the single point as both ranges have incredible glacial forms! OP is on to something for sure. Differences in the two ranges are fascinating. Like for example, why are there NO lodgepole pine in the LRR or hardly any flowing water in the big U shaped valleys? Anyway rain shadow effect is definitely one component, difference in soil moisture in dolomite derived soils and bedrock versus versus granite derived soils is another component. Oh also... There are rock glaciers in the LRR. Not the usual type of glacier we're looking for, but still made up of permanent ice that moves from year to year. Cool vid.

[@jmelande4937]

Have you done a video on the seven devils? I’ve heard that the seven devils have a unique geology compared to the surrounding regions.

[@shawnwillsey]

Not yet. So many places to get to...

[@lauram9478]

❤

[@rickmessina5396]

Been interested in looking for placer gold deposits in the Saw Tooth range. What are your thoughts.?????? Thanks….

[@pauldudakadanielthomson8890]

Years ago, Lake Bonneville drained out thru Idaho ,, thus the Snake river then into the Columbia river was where the billions of gallons of water went . All that water probably formed Twin Falls ?

[@georgesheffield1580]

The sawtooth caught the moisture ,every thing to the west was in a rain shadow .

[@Diana1000Smiles]

I can see Idaho from my backyard. 😊

[@slickjames2541]

there actually was a small glacier that persisted on the north side of Snowyside peak into the early 1900's

[@georgemetz7277]

So was there a Stanley Flood like Missoula floods?

[@toughenupfluffy7294]

Big ole' batholith.

[@hmtnhk]

Which month was this video shot?

[@shawnwillsey]

late June

[@kruelunusual6242]

It’s a safe bet the ice will return.

[@GregInEastTennessee]

Great video!!!! Were you east or west of the mountains? Which way it north and which way is south in the video? You mentioned Eocene. Do you think the Sawtooths were formed when Siletzia hit? I get to Ellensburg, WA on Sept 8th and will be in the area through Thanksgiving or beyond (I am auditing Nick's 101 class). I will be in the Sawtooth area for sure because they fascinate me. Maybe I could buy you lunch one day if you're in the area? PS: Don't let Nick hear you say bulldozer or conveyor belt. He HATES those terms! LOL

[@WJV9]

He says early in the video he is looking west and he is in the Salmon River valley, so he is definitely East of the Sawtooth range.

[@GregInEastTennessee]

@@WJV9 I guess I missed it. Thanks! :)

[@marinangeli3250]

If you will be passing through the Stanley Basin in November, be prepared for cold, snowy weather... I have seen a few inches of snowfall overnight, in July, up there. Very cold mornings in the basin but warmer at higher elevations (sounds counterintuitive but has to do with cold air settling into the lower reaches of the basin during the night), warming to comfortable temps by noon or so. In times past, snow was a pretty sure bet by September but, with the changing climate, all bets are off. Check to make sure Banner summit, on highway 21 to Boise, is still open otherwise you'll have to stay on highways 75/93 all the way up to Hamilton MT or maybe even Missoula. I've endured less than favorable road conditions on the summit between Salmon ID and Darby MT early in the fall/winter. At any rate, Greg, you will love the geology there... the Sawtooth Range is spectacular, especially after a fresh snowfall in Autumn, when the aspens are turning colors. Fall is truly one of the most beautiful times to be in the Stanley Basin.

[@GregInEastTennessee]

@@marinangeli3250 Thanks for the tips! I'll try to remember them. Hopefully I'll be there about mid-Sept.

[@marinangeli3250]

@@GregInEastTennessee My pleasure, Greg... I so love for people to enjoy what Idaho has to offer, especially the Sawtooths. When, along your way, you pass through Bellevue (on highway 75, halfway between Twin Falls and Stanley), please feel free to stop by my companion's vintage guitar shop and say hi (Rosewood Music, right on the highway next to Mahoney's Bar & Grill... can't miss it, just call the number in the window if no one is there, we only live a few blocks away). By the way, September is the best time to visit Stanley, as it is in the slack season between summer tourism and the fall hunting season. Quiet, tranquil and beautiful.

[@DrewWithington]

So did Slarti Bartfast really design the fjords?

[@inyobill]

I'm a'gonna guess rain shadow.

[@nitawynn9538]

I’m not familiar with the Sawtooth Mountains. They’re very impressive. Thanks.

[@sonnyblu6299]

I thought you said we were going to explore... 😞 Only verbally obviously.

[@Fryed_Bryce]

You are literally the only complaint i have seen on any of his videos. You're probably just a complainer

[@Brian_yeah_that_brian_Strang]

They look taller

[@krrrruptidsoless]

Do crows fly 70 miles easily?