Devils Tower: A Volcanic Neck or Not?

[@shawnwillsey]

You can support my educational 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 or here: buymeacoffee.com/shawnwillsey

[@RWBHere]

Nicely explained, Shawn. That makes a lot more sense than the standard explanations. Thank-you. 🙂

[@Pay-It_Forward]

Is it possible it cooled & hardened under ground. Then many years later got pushed upwards by more recent activity, rather than erosion removing the soil? This isn't that far from Yellowstone Caldera which does rise & fall. My guess would be a possible Yellowstone side vent, which barely made the surface, cooled, then later pushed up when under pressure, then cooled again.

[@revvyhevvy]

I watch your posts as an homage to a HS friend who I lost a few years after college. He had become a geologist, and was employed in Alaska by a petro exploration company when the helo he was a passenger in went down. He was a good friend, and I think of him whenever I see a post of yours. Thanks for your posts and the memories of him.

[@shawnwillsey]

So glad you are able to still connect with him.

[@emmabradford137]

nice tribute

[@nothanks3236]

That looks like a gnarly climb. Be safe!

[@brianjacob8728]

agree on the intrusion. the surrounding sediment layers were probably eroded away during the younger dryas, when there were megafloods from the melting glaciers flowing thru this region, leaving the exposed columnar formation.

[@billybobwombat2231]

Pleasing to not see comments depicting it as a tree from the time when giants ate their oatmeal under its shade, restores my faith in humanity....a little bit. Thank you for taking the time to explain and post your informed educated insights 🙂🦘

[@StacyBaldwin-qv5cj]

Funny how no one has ever said definitively how it was formed. However every one says it's not a tree, even though visual evidence says it's a tree.

[@billybobwombat2231]

@@StacyBaldwin-qv5cj funny how it's an igneous rock and the uninformed and wilfully ignorant don't even want to know what igneous means

[@StacyBaldwin-qv5cj]

@@billybobwombat2231 ok, show me one rock formation from any active volcano that looks like this.

[@billybobwombat2231]

@@StacyBaldwin-qv5cj go study geology

[@StacyBaldwin-qv5cj]

@@billybobwombat2231 ok so what you're saying is there aren't any.

[@davidsabbagh6815]

It's great to see your subscriber count is climbing. I very much enjoy the videos you create explaining the many wonderful geologic stories of the west.

[@NeilMacMillan-fb3hd]

to Shawn Willsey your geology videos are excellent I suggest you do some videos in magnificent British Columbia

[@shawnwillsey]

Thanks. I'd love to get up there. Have been to Victoria, Vancouver, and up by Squamish and Whistler.

[@terryatpi]

Awesome. Cutting edge theory. Thanks.

[@rickmessina5396]

I climbed the tower back in the early 1970’s. Was a can to leave your name and date when climbed. Spectacular view from on top…..

[@WilliamLeue]

The intrusion explanation makes sense to me. The columnar appearance is quite similar to what we see in the New York Pallisades, which are a known igneous intrusion into sedimentary rock layers, and which has the same kind of columnar arrangement.

[@NeilMacMillan-fb3hd]

wishing you a merry Christmas and happy new year

[@Backroad_Junkie]

If you decide to visit, avoid August. It's when the Sturgis Motorcycle rally takes place, and stay away unless you plan on going to the rally, lol. The entire Black Hills area's worth the visit, Custer State Park, Mt. Rushmore, Jewel Cave, Wind Cave, Badlands National Park (and Wall Drug), etc. Just not during the Bike Rally...

[@majirayne1063]

I was 38 before i heard the word 'sus out" and had not ever found it in my dictionaries - field zoologist

[@steveking6204]

It's not clear to me how the intrusion hypothesis would lead to a different direction of cooling. In either case the hot magma is surrounded on three sides by much cooler material; the lines should develop in similar manners... Could you clarify please? Perhaps the outer portions of the tower which had cooling lines running perpendicular to the present day lines have eroded away and are lying at your feet in the rubble?

[@AManIsNoOne67]

Think in terms of insulation. Thick sedimentary layers, more insulation. Oh, sorry, I'm not the geologist. Am I right, Shawn?

[@ChrisPihl]

I'm with you Steve that it's not clear why there would be an obvious difference between the intrusion and neck. I confess that it actually seems more likely to me that a volcanic cone would be hot, and when it stops flowing the "neck" would cool from the top down.

[@737smartin]

I think he’s distinguishing between a neck within a conical mountain vs an intrusion below level ground. Technically, you could have a neck with a volcanic flow that doesn’t build into a conical mountain that would cool and look identical to an intrusion that never reached the surface. 🤷‍♂️

[@inkermoy]

sounds like it's just a difference in not being a volcano at all, but magma breaching below the surface but never erupted into a volcano. Devil's Tower... the volcano that never could.

[@agmartin2127]

Not sure if i'm reading the question correctly, but if you're referring to the difference in appearance between the top half and bottom half, it's due to erosion rates. At one point, the entire tower was under ground. Then a robust erosion period, likely during an ice age sequence, eroded several hundred feet of the surrounding countryside /softer rock away. Erosion stopped for tens of thousands of years (hence the weathered appearance on top). A second episode started and eroded the soils / rock away from the lower half. My guess if you came back in several hundred thousand years, a few more hundred feet around the current base would be gone, and Devils Tower would be taller than it is today. There are rivers in Wyoming and elsewhere that at one time were several hundred feet above their current level. These rivers eroded the rock below and bore down through mountain ranges. So when you see one of these, it makes no sense (rivers can't flow up and over mountains) until you factor in the huge amount of time, and the vast amount of erosion it would take to cut a river channel right through a mountain range. Same concept at Devils Tower (but just erosion, no rivers, and geologic time).

[@philipdavis9324]

Is the base of the tower made of the same material as the columns? If so does the intrusion penetrate the lower rock?

[@James-xf4pc]

Thanks so much for what you do. You are like my really smart little brother that has resparked my interest in rocks, earth and history. I found you because of Iceland. Used to live there.

[@Madshadowgolem]

Something I have wondered about this formation is why the columns are so large compared to other places with similar formations (Like the Giant's Causeway in Northern Ireland). Your videos make me wish I had gone with geology in school!

[@Mistydazzle]

You can always seek out the knowledge, now, not as a Geology student in college, but by reading the research of Geologists and their other topic-related professionals. As Shawn said, the interpretations are sometimes changing, and you may be able to follow the latest studies, online, in whatever topic of interest.

[@abandoninplace2751]

Height? Width? Either way, lots of reasons for differences. Composition (felsic phonolites or whatever vs. the seemingly more common mafic basalt columns), thickness and extent of initial emplacement, whether it is intrusive or extrusive, (cooling rate and pressure), rates of cooling (which also affect texture), rates of weathering (environment vs. composition), how much of the formation is actually exposed subaerially, and how long it's been exposed. All these things affect each other, and may have an effect on your definition of large in this case. Disclaimer: ianag, ymmv.

[@tomlof8941]

it's an Achillies tendon from a giant that stood like 300 meters. . every bit around that Achillies tendon that stands is just the part above the heel. the rest around the area is the rest of the body. When you are able to see and understand what I write, you will never look at rock and mountains. or life and reality the same. the top you can see the tendons are wrinkled and snaped up, it's the wrinkle zone. This has nothing to do with volcanos. everyone open your brains , have you ever seen a volcano make rock and shapes like this. That narrative is ridiculous.

[@TheHighest-x6k]

@@tomlof8941 it's was a giant 🍄

[@bluerendar2194]

If you mean lateral/cross-section size, that is from the composition (shrinkage ratio, stress-strain relationships etc) and cooling rates. If you mean vertically, for the most part, this just seems taller due to more of it being exposed and/or having experienced less erosion.

[@ms.cussout6227]

Thank you! Being Icelandic living in Southern California, I’ve been following your updates on Grindavík and now, following you here to Devil’s Tower, I feel like an accidental geology student (I’m an artist). I’ve always been fascinated with Devil’s Tower but have never been there myself. I look forward to following your climb tomorrow. Good luck!

[@robertlee3778]

I visited Devil's Tower about 8 years ago, and drove around the base. It is a very impressive structure, indeed. I am looking forward to see your video of the climb!

[@lealoo6287]

I've been to Devil's Tower several times. The last time, I walked around the whole thing and watched and listened to 2-man climbing teams go up. It was fascinating to me how clearly we could hear them talking to each other while climbing. I've always thought it looked more like a giant tree stump lol.

[@mramsch]

And you are right: Devil's Tower does _look_ like a gigantic tree stump. From a distance. Not looking too closely. :) Fortunately, science is not fooled by superficial appearance and hearsay, but looks closely, examines the composition and age of the material, etc. I'm a big fan of Shawn Willsey because of his clear, unbiased, evidence-based thinking coupled with an infectious curiosity about the wonders of the world and his wonderful ability to explain science in layman's terms while still being accurate.

[@pauljohansen8043]

I live in SD and just visited the tower this summer. It is absolutely unique.

[@Kdrive23]

I stayed in Rapid City in 2020 and explored the region. Devil's Tower was by far my favorite site/sight in the area. Loved the drive out there from RC, and loved the trail around the tower.

[@robertdiehl1281]

It’s an awesome place. And the segments of rock the columns that have fallen down are massive. Very cool video.

[@mikeyoung9810]

Interesting place to visit. Spent the night there once at the KOA nearby which showed Close Encounters nightly outside with the tower in the background. Just finished the video which made perfect sense. So the rock around the intrusion was softer rock so it's weathered away faster?

[@ericcox6764]

I love Devils Tower! I climbed it back in 2003 via the Durrance route. I try to visit there every couple of years. If you ever visit there and need a place to stay, I highly recommend staying with Frank Sanders at the Devils Tower Lodge. I hope to get back there later this year.

[@jsnsk101]

i havent been to devils tower since 92, but i was always under the impression it was an intrusion and not a neck. As a non geologist the neck theory makes no sense, it had to be trapped way underground

[@jeffrysmith8200]

Most of the columnar jointed rocks that I have seen are basaltic and appear to have formed at relatively shallow depths.

[@shawnwillsey]

@@jeffrysmith8200 Columns can form in many types of igneous rocks.

[@cacogenicist]

@@shawnwillsey - Do I recall correctly that columnar jointing can even occur in rhyolitic ash-flow tuff?

[@jonmurraymurray5512]

@cacogenicist I never saw it on the Big Island of Hawaii when I lived there.

[@Boycott_Wendys]

It's actually a tree stump😊

[@MrSiwat]

Wow! Absolutely beautiful place and interesting content. Thanks so much for your channel.

[@beeble2003]

Yes, Devils Tower was indeed the first National Monument to be declared, in 1906. Amazing place! For anyone who's not been there, yes those are full-size trees. The thing is _enormous._

[@apolloskyfacer5842]

🤣

[@00leaveralone]

Jack & the Beanstalk exactly like NASA: a myth and a fairytale. 😅

[@darrenn897]

Massive building thats been melted by powerful direct energy weapons in the past vitrifying stone and liquifying it.Happened worldwide and its being hidden from us, aint no tree

[@emmabradford137]

it DOES look like the base of a beanstalk or tree@@00leaveralone

[@00leaveralone]

@@emmabradford137 yes Ma’am….perhaps Giant people climbed giant trees in another version of our earth? We see our earth was ‘plowed’, like a farmers field and new civilization built around some of the remnant features of the old earth and old civilizations. In the Bible, Jacob has a vision of angels ascending/descending a ladder from heaven and he rested his head on a rock, or pillow. Funny but Queen Elizabeth used to sit on her throne and claims are made that the visible stone under her seat is ‘Jacob’s Pillow’ stone; stolen from relics belonging to ancient Hebrew Israelites. There’s the myth of the ‘lumberjack’ Paul Bunyan, with his giant 🪓 and ‘blue’ ox named Babe. Just some old myths & stories concerning giants that could go between realms much easier than we know how today….seems like anything was possible a long time ago.

[@ReclinedPhysicist]

Thanks!

[@shawnwillsey]

Much appreciated. Thank you.

[@runninonempty820]

Yes! I've been there. I was most impressed by it's immense size. Just an amazing feature.

[@karentaylor83]

It is so beautiful in person. Good luck with the climb.

[@katesommerville7217]

An impressive structure 😊

[@John-ir2zf]

Even if it were formed intrusive, wouldn't it still have the cooling pattern that would develop if it were a volcanic neck ?? The columnar cooling pattern would still be more towards horizontal because the intrusion would be surrounded on all sides by cooler host rock. I know the drawings look nice and seem to explain it somewhat, but they are missing the 3 dimensional aspect in the sense that both scenarios have the cooling basalt surrounded by host rock that is cooler.

[@Riovientoselva]

Sorry for the language but i suspect you speak Spanish . Muchas gracias por el video , ese es un lugar al que siempre hubiese querido ir, pero que muy probablemente no sucederá. Pero el video ha cumplido lo que hubiese querido hacer: mirar y determinar las rocas en la base mirar los alrededores y después intentar subir ( un video que espero) Gracias por el magnifico video y por la información.

[@JasonKahn]

I love the Lakota legend for how the Bear Rock formed.

[@toddaulner5393]

@@JasonKahn , yeah, those young native girls are probably tired of waiting up there!

[@Raven-Creations]

You didn't explain the different form of the pedestal. Is that the remains of the rock through which the intrusion flowed, or is it part of the intrusion which the column formation never got down to? If the latter, it seems odd that there's such a definite termination level for the columns. I would have thought some would extend deeper than others, forming a "frayed" effect at the bottom.

[@rollsandfloats]

I was wondering if you could resist climbing it! Looking forward to the next episode and some good crack climbing :) BTW, your explanation makes a lot of sense. Thanks as always!

[@susiesue3141]

My husband and I went to Devil's Tower on our anniversary trip in 2010. That was the year we got married. That was a very interesting video full of great information.😊 Thanks for sharing with us.

[@beeble2003]

I'm a bit confused what you mean by saying that the column fractures form perpendicular to the cooling direction. If there's a pool of lava on the ground, it's being cooled by the rock below it and the air above. So the cooling direction is vertical: the heat is flowing upwards and downwards. But you also said that the fractures would be vertical. So aren't they parallel to the cooling direction? And, in the intrusion model, why isn't the intrusive magma also cooling from the sides, just like the volcano neck? That model seems to rely on the magma only losing heat from the top, which doesn't seem reasonable.

[@charlesgregory3747]

If I may offer an observation. As seen during Fagradalsfjall eruptions, freshly erupted scoria cones are VERY hot in their interiors, so it is possible this neck developed in a setting where the surrounding cone was still just a few degrees below melting point, and so it was an even better insulator than cold rock. This would contain the heat of what essentially would have been a lava lake, with cooling predominantly progressing downward from the top. The flaring at the bottom does suggest that at depth where the conduit was passing through original (cold) rock the sideways-in cooling was happening. If we dug down into the uncolumnated base, would we indeed find sideways columns?

[@patmayer7222]

,,,,,land o' lakes,wi....here,...tnx for this awsome view of this monolith....truly one of our planets best singular feature,....invokes ancient landscapes in a imposible past,,,,...almost does not make sence looking at it now...a perfect sunlit perspective,,tnx,,.pat&family.

[@prokopzavada6505]

Hi Shawn, we did some research on Devils Tower and nearby phonolite Missouri Buttes. I agree that the key for understanding the original shape of the monolith is the columnar jointing pattern. Since the collonades are vertical, a laterally extensive lava or igneous body, like a lava lake or a laccolith, is the most likely scenario. We proposed a lava lake emplaced into a maar-diatrame volcano, because both the Devils Tower and Missouri Buttes are associated with outcrops of the phreatomagmatic breccia. We also did some cool physical modeling with liquid plaster to support our explanation. Check the 2015 open source publication in Geosphere journal (Devils Tower (Wyoming, USA): A lava coulée emplaced into a maar-diatreme volcano?).

[@Barley150]

Thanks for another informative and fun posting, Dr. Willsey. You have aroused an interest in geology that, at 90, I hadn't expected. I suppose you know the Native American myth -- that some girls were playing outside the safety of their village when a man approached them with evil intent. They ran, and as he chased them, he turned into a bear. They jumped to the top of a giant tree trunk, and he almost caught them, but the stump began to grow, fast, and they escaped. The columns are tracks of the bear's claws. The stump stopped at its present height, and the girls ascended to the heavens and became the Pleiades.

[@professorsogol5824]

What about the difference/contrast we see between the base or pedestal and columns of the column itself? what rock types and structures do you see there?

[@shawnwillsey]

Same rock type.

[@professorsogol5824]

@@shawnwillsey and structure? is it also columnated? if so, we don't we see the columns now? if not, what does it tell us about the cooling process?

[@Riverguide33]

I learn something every vid, Shawn. 👍

[@richardlawton1023]

Thanks for the update. Your passion really shows in them. Stay safe God bless

[@frankblangeard8865]

The sketch at 6:25 shows a steep sided stratovolcano. A shield volcano would not cool in the same way.

[@owenkittredge3433]

Why geology is so fun, you get to go to lovely places!

[@brianlock7177]

My interpretation of Devil's Tower differs a little from yours. The pattern of the columnar joints suggests that we have the central part of a lava lake sitting in a crater. the base of the lake would have been lens-like angled upward and pinching out to either side of the remnant, while the top of the columnar mass was a horizontal lake surface.

[@Dragrath1]

It is probably worth noting that phonolite is apparently an extrusive rock with the intrusive counterpart being a rock called Nepheline syenite which is an intermediate siliceous lava typically seen from volcanoes like Mt. Erebus of Antarctica Tenerife and Mt. Vesuvius of Italy so if it was extrusive in origin it would probably be more explosive in nature. That said if the volcanic magma body in question is larger could the visible columnar core not be the remaining core of the magma body? I ask since there are some near hexagonal angular fault sections facing laterally outwards to the outer left section which suggest to me that this could be a conduit if the majority of the phonolite conduit has already eroded away. Perhaps this was a system somewhat like the modern Mt. Erebus? I.e. a lower section of an open phonolitic(syenite) magma conduit erupting from an alkaline rich stratovolcano. That might explain why you have both small and large crystals as the melt could have convectively cycled. So maybe not the neck so much as the shoulders of the volcano?

[@whispermason8052]

I was always taught Devils tower was an ancient underwater hydro thermal vent. That was in standard high school. It would make sense that the top would be cooler in that circumstance and would explain the shape.

[@whispermason8052]

But that brings up a problem.. how come all your life you were taught different.

[@flamencoprof]

How does this compare to a confirmed volcanic neck?. Are there examples exhibiting the columnar alignment drawn in the counter-example? What explains the discontinuity below the columns?

[@sergiovelazquez1259]

Has anyone know why there is a difference in shape between the columns and the pedestal?

[@chanvalentine8283]

Well, I didn't expect to learn something new today. When Close Encounters came out, my dad said it was a fossilized tree. 😂😂😂. He made roads for the Forest Service.

[@user-wk1mw9nj3i76]

It’s interesting to follow your thought processes or scientific problem solving in each video. You’re showing not just the facts but also how to think like a geologist. I’m a music professor who is enjoying your excellent teaching as well as the geology itself. On a different topic, I would vote in favor of changing this place’s name back to the native peoples’ “Bear’s Lodge.” It always seems slightly derogatory and primitive to call it “Devil’s Tower,” whereas there’s an illuminating story behind Bears Lodge. Congrats on cracking 70,000 subscribers. Go Geo Team! 🎉

[@whtwolf100]

the devils tower is actually a pretty good name since the natives thought evil spirits (or at least a very angry god) lived there. also...it's definably less primitive.

[@pixelchi]

Decades ago our university summer geology field camp visited Devil's Tower and the geology explained then was similar to your intrusion' with subsequent erosion theory. Phonolite Porphyry was named because of the unusual or melodious :ring" sound emitted by striking the porphyry with a rock hammer. Climbing the tower back then was not encouraged by the BLM as I recall. Those were the days!

[@jackprier7727]

Okay, thus the "phono"- thanks-

[@johnlaforte700]

Great info Shawn. Have a great climb. 🙏😎

[@J0hnC0ltrane]

Just revisited this video which maybe the first one I watched. Just as a follow up I watched a PBS terra video that termed the formation as a laccolith, an intrusive rock with a dome-shaped upper surface and a level base, just as you mentioned. Cold beans right. Thanks for all of your work and perhaps great fun.

[@carlcarnein2569]

A couple comments. First, phonolite doesn't contain quartz, especially visible quartz. Second, I'm not sure the rock you looked at at the beginning came from the material that has columnar jointing--it could have come from the material at the base. Third, is the material at the base sedimentary? You postulate that the columnar rock intruded sedimentary rocks, so I'd expect to see some sedimentary rocks in that area around the base. Fourth, if the columnar mass is indeed an intrusion into what were presumable colder sedimentary rocks, they why don't the joints do exactly the same thing that you suggested if the columnar rocks are a neck? They should start out horizontal at the bottom and sides and become vertical at the top. I've puzzled over this feature too, and I still don't think we have a plausible explanation (yet).

[@shawnwillsey]

Point #1. My mistake. Thanks for the correction. No quartz in phonolite (not a very familiar rock to me). Point #2. Rock is identical from columns to base according to my observations. Point #3. There are red Triassic sedimentary rocks (I point these out in the climbing video posted after this) exposed near the monolith's base. Point #4. I'm confused on this still as well. Thanks for your questions.

[@dreamyjeannie3385]

Thanks Shawn, very interesting explanation of Devils Tower. I visited in 2018, it is an unusual formation for sure. Thank you for explaining our earth! 🌺

[@raymonddaly2612]

I was always under the impression that Devils Tower was a lacolith. I used a diorama in the American Museum of Natural History (NYC) to lecture my students on the geology of the area and include some of the native American legends. The dioramas in the Museum allowed for a very educational field trip for a minimal cost.

[@johnizitchiforalongtime]

From an early age, i knew it was volcanic. An intrusion i didn't know. Loved your explanation.

[@nontraditional_student]

in 1:30 - 1:31, there's an object that appears and disappears on the top right corner of the tower. I was watching this to find out about the formation but now I am distracted with this. I hope its not just a bird. :)

[@michaelbingham5656]

I also climbed it in the 90s (as a geologist)… You should show a picture of the mural in the visitor center showing First Nations myth of origin…. Loved your presentation of of the geology!

[@agmartin2127]

I've climbed Devils Tower via the ultra classic Durrance Route, known as the most difficult 5.6 route in America. Jack Durance had climbed the tower in 1939 in what I believe was the second assent. Then in 1941, A 29-year-old daredevil, George Hopkins, parachuted onto Devils Tower, became trapped on top, and remained there for six days. His 1500 feet or so of hemp rappel rope, dropped later with other rescue supplies, became hopelessly tangled, and he was 100% stuck on top. Jack Durrance (K2 fame as well) was summoned from Dartmouth and took a train to the area. He arrived, climbed the Durrance Route again, and rescued Mr Hopkins. Yes indeed, a classic route! - Also, and it may have been mentioned, but the top and bottom half are significantly different in appearance due to two surges / episodes of weathering and erosion. The upper half is much more weathered and fractured than the bottom half. --- Neat episode Shawn!

[@norml.hugh-mann]

Very interesting comment, thank you for the knowledge

[@stainlesssteellemming3885]

Visited Devil's Tower in Summer this year .From memory, the intrusion model is the one being displayed in the visitor's center.

[@hestheMaster]

I first recall seeing Devil's Tower in the 1977 movie Close Encounters of the Third Kind. Back then it was assumed the columns formed by cooling of the lava rock because it was the area in an ancinet inland sea and the identical base rock was below the water level. They hinted the whole thing has been lifted over time and that rock was harder than the surrounding sedimentary rock that was the bottom of that sea. The sedimentary rock has been eroded away by time and the elements but that was not the whole true story. It was actually a Maar-Diatreme volcano and not a volcanic neck. I'm willing to bet there a lot of these scattered around in the Earth's oceans as they a basic start to volcanic formation but they are rarer to see inland in the middle of a continent like in Wyoming. I recommend looking up Maar-Diatreme volcanoes to see what one can visualize as to how the tower was formed. I'm sure the top side view will remind folks of the basalt columns of eastern Washington state that are so prevalent there . Great video professor Willsey!

[@OmegaSparky]

This means something! 👽 😂 Thanks for the explanation. I'm curious about the difference between the columns and the base. If the base is made from the same material, what caused it to cool faster? (Assuming that since we don't see the large columns continue downward)

[@garyb6219]

I didn't see the UFO landing base when I visited.

[@darrenn897]

This was a massive building thats been melted or vitrified by scalar direct energy weapons in our past.Its happened worldwide and they are hiding it

[@maggiem.5904]

Yes, I am perplexed about this too. I didn’t catch an explanation of this.

[@3xHermes]

Yes intrusion theory works for me. Thanks!!

[@mikebartram8424]

Does your hypothesis account for being under water? Around the time it was believed to be formed, the area likely was a shallow sea. I know not far away they have found fossils indicating such. I would think it closer to the Hawaiian islands in build.

[@curtnichols]

Thanks for the vid. Are there known examples of the lateral joints as drawn in the volcano neck drawing, in the form of a volcano neck?

[@brendanacord]

Fascinating and really quite straightforward explanation. Question: the evidence for it being an intrusion as you show versus a volcanic neck within a cone is visible from any picture taken from far away, it should be clear to the field as a whole, any idea why the older interpretation persists and what brought you to the point of changing your interpretation? Thanks again for sharing!

[@winstonnian]

awsome video thank you so much!

[@cacogenicist]

We have exposed intrusions in the Willamette Valley, especially around Eugene, with columnar jointing. Shallow Intrusions were into since-eroded-away sedimentary layers.They look a lot like the little buttes you might see in the Boring volcanic field, but are actually intrusive rather than volcanic, as I understand it. That shape would make them laccoliths, maybe?

[@almaadams3631]

This whole structure could have formed under water as well.

[@judierickson7166]

As Always, Learning is cool!

[@Turboganz]

As a geology undergrad in the1960s, I would periodically hear two of the department profs. debating Devils Tower. One held to the volcano notion, the other proposed that it was the supply stem of a laccolith. I'm surprised that after all this time, the arguments have not been settled by using the more advanced tools of analysis now available.

[@jackkip]

Love devils tower. Saw it for the first time 3 years ago. I hope you climb went well saw several climbers when we visited. It looked so scary. I was just fine staying on the ground ☺️

[@irenafarm]

Thank you for another really informative video! I'm now wandering around my (I thought!) boring area (Charlotte NC) and finding out it's actually REALLY amazing!

[@SkepticalRaptor]

Wow, I just learned something new, given that I always thought it was a “volcanic neck.” Your explanation makes total scientific sense. BTW, I just noticed you broke 70K subscribers. I was there when you had

[@shawnwillsey]

Thanks for being a loyal viewer from the early days. The Iceland drama was a big boost. I will continue to try and connect with folks.

[@mikelouis9389]

Is the composition of the base the same as the tower itself?

[@SamtheIrishexan]

With the area around it eroded away so much I wonder if it was an intrusion that happened during snowball earth. A glacier on top of the sedimentary rock would keep them cool enough to assist in the process I would think.

[@ruthwilson1936]

So if it is an intrusion, and it cooled in situ, does that indicate that the magma was thicker, less fluid? Or are we left with the lower part of the original rising magma, and the upper part flowed/erupted, and spread out, and was subsequently eroded away?

[@MikeCurtis1958]

I wisited there in the summer of 2020. Walked around the base. Very cool. I, too, understood it to be intrusive, then, later uplifted (Laramie Orogeny?), then, deeply eroded all around it. You didn’t comment on the uplifting and subsequent erosion. It would be interesting to know if you see it that way now.

[@marionnadeau8457]

So, Shawn, is this like the intrusion happening in Iceland near Grindivik?

[@loisrossi841]

Interesting, thank you.

[@toughenupfluffy7294]

A GSA paper on Google Scholar ("The Devils Tower, Bear Lodge Mountains, Cenozoic igneous complex, Northeastern Wyoming," by Karner and Halvorson, 1987) mentions that the columnar jointing in the upper collonade section (btw, Devils Tower is the largest example of columnar jointing in the world) may have been emplaced underground _horizontally_ , then bent upwards due to differential thermal gradients (if I'm interpreting the paper correctly). This would explain the odd bend at the entablature section towards the bottom. Another interesting resource is the National Park Service. Google NPS, Devil's Tower, 'How the Tower Formed.' This lists 4 different theories on the Tower's formation.

[@bsideberg6082]

I’ve been there twice. An impressive structure. There are very similar columns at The Devil’s Postpile in California.

[@rickc4317]

When I was there in the mid 70s (I was overseeing a seismic crew nearby as a geophysicist working for Amoco), I was told it was an intrusion. Seems both explanations were being offered. BTW, did you see any alien spacecraft?

[@Backroad_Junkie]

When I was there, I was so disappointed to walk to the other side, and there was no alien facility, lol....

[@rickc4317]

@@Backroad_Junkie They must have just left. Sorry you missed them. :-)

[@Backroad_Junkie]

@@rickc4317 Yeah, they told me the same thing when I was in Roswell, lol...

[@rickc4317]

@@Backroad_Junkie 🙂 Very good!

[@EmilySmirleGURPS]

When an intrusion is forcing its way up, wouldn't it cause a bit of a blunt cone shape anyways by deforming the land? Is that why you hypothesized it was in a ravine or valley, so that the vertical deformation countered the downward slope of the land to produce a roughly flat surface?

[@jackprier7727]

And-if magma was punching up then through it would be weakest in a valley or gorge-

[@valoriel4464]

Thx Prof. ✌🏻 grt vid Climbing this sounds frightening. Be safe. Edit. Whew. Your vid of the climb is up. U made it. 😅

[@Jayne-z5s]

Wow....i havent seen this before its amazing, quite a statement piece! I see this is a month ago? What is the next days climb link? I would love to see that as well.😮

[@michaelturner6358]

Have been here, a beautiful and fascinating place.

[@superchi31]

Watch out for the aliens lol

[@nozrep]

haha yah me, the only thing i really know of devil’s tower is from that 1980s movie. Be aware!😅

[@NuncNuncNuncNunc]

Just from the geometry of a vertical column like this, doesn't cooling need to be normal to the surface all the way around above the pedestal? Does this mean the tower was once embedded in at least two distinct layers, the upper layer being uniform?

[@CFEF44AB1399978B0011]

That makes sense, similar to North table mountain in Colorado, where the columns are vertical in its a an igneous intrusion into a sedimentary basement rock. The columns are vertical.

[@HulaViking]

I was an undergraduate at the School of Mines in Rapid City in the 1970s. We learned it was probably a pluton. I do not recall anyone back then thinking it was a volcano.

[@jackprier7727]

Thanks, a mystery has light shed onto it, and of course it makes sense-

[@rjansen6874]

A conspiracy theory says it's an old tree stump according to a buddy of mine (yes I know it's nonsense) but it's kind of funny considering how far-fetched it is

[@mikewatson4644]

WHAT?? Are you saying it ISN'T a tree stump??

[@shawnwillsey]

Except there are large number of people who think it is. Quite disturbing.

[@ryanjohnson3615]

No, I'm pretty sure it's where the land was raised up to protect some Indian maidens from a giant bear, -hence the claw marks on the sides. Pretty obvious really.🤔

[@agmartin2127]

The Story of Jack Spriggins was published in London by J. Roberts in the 1734. It details the theory you mention, that it could have been, in his version , a petrified stalk (old English translation). The petrified “stalk” , or volcanic neck as later clarified, was eroded away after Jack climbed it. The theory is being tested to this day and has yet to be disproved.

[@Anne5440_]

Along with the intrusion was there also subsequent uplift in the area?