Devils Tower: A Volcanic Neck or Not?

Journey to Devils Tower National Monument with geology professor Shawn Willsey to investigate the geology of this iconic monolith. GPS location: 44.58996, -104.71709
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[@shawnwillsey]

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[@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.

[@roberthevern6169]

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

[@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.

[@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...

[@shadowgolem9158]

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.

[@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.

[@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😊

[@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…..

[@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!

[@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.

[@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).

[@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.

[@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.

[@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.

[@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!

[@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.

[@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.

[@pauljohansen8043]

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

[@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-

[@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?).

[@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.

[@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.

[@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.

[@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?

[@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.

[@runninonempty820]

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

[@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?

[@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

[@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!

[@terryatpi]

Awesome. Cutting edge theory. Thanks.

[@Riverguide33]

I learn something every vid, Shawn. 👍

[@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.

[@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!

[@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!😅

[@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.

[@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.

[@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.

[@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?

[@karentaylor83]

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

[@kevint1910]

There is another outcrop like devils tower near Yakama it forms a headland along the highway that comes over mount Rainier. in both cases and at devil's post pile the formations look crystalline in nature so i would expect them all to have formed under similar conditions to smaller crystalline structures of the same shape such as quarts. The headland nw of Yakama features "posts" that start vertical at the top descend vertically for most of their length then curve toward the horizontal plane where they join the "pedestal" base rock from the side so puzzle me that one batman? can simple convection in a cooling and solidifying liquid account for that shape or does it require a superheated ultra high pressure water component?

[@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.

[@nothanks3236]

That looks like a gnarly climb. Be safe!

[@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.

[@JoseFernandez-qt8hm]

you mean it wasn't a close encounter of any kind?????

[@MrSiwat]

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

[@marionnadeau8457]

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

[@lawrenceanovitz5246]

Also note that the texture you describe (large feldspar crystals in a fine-grained matrix (did you say it was also porous?)) is not really classically intrusive (e.g. granite or gabbro). It suggests partial crystallization at depth followed by extrusion, or at least much more rapid cooling. If I heard right that it is porous that would suggest the pressure was at least low enough for the gases to exsolve. This could be consistent with extrusion or intrusion at a shallower depth than the original crystallization. Thanks for the nice geo video.

[@shawnwillsey]

Texture suggests shallow intrusion or hypabyssal.

[@loisrossi841]

Interesting, thank you.

[@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.

[@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! 🌺

[@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.

[@katesommerville7217]

An impressive structure 😊

[@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!

[@davidcook1714]

Certainly an interesting feature of the landscape and your explanation does make far more sense for the way it was formed. Have a good climb and look forward to seeing it up close and from the top.

[@3xHermes]

Yes intrusion theory works for me. Thanks!!

[@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.

[@richardlawton1023]

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

[@stainlesssteellemming3885]

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

[@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!

[@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.

[@johnizitchiforalongtime]

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

[@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.

[@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.

[@johnlaforte700]

Great info Shawn. Have a great climb. 🙏😎

[@stevewhalen6973]

Thanks!

[@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 ☺️

[@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.

[@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!

[@bsideberg6082]

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

[@Bigandrewm]

The intrusion idea doesn't completely make sense to me either, looking at the direction of formation of the columns. All of the rock intruded into also is a heat sink, so the lava would still need to cool/columnate toward the perimeter, not just vertically, unless one adds other factors: maybe the rock intruded into was a very poor heat sink and the material at the "surface" a very good heat sink that biased cooling in that direction, perhaps something like an ocean with strong currents that carries heat away. On the other hand, if there were non-vertical columns, they could simply be eroded away by this point.

[@darrenn897]

Remnants of a massive building thats been melted or vitrified by scalar direct energy weapons in the past. Happened worldwide,go research

[@frankblangeard8865]

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

[@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!

[@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?

[@jaw147]

When I visited Devil's Tower in 2005, my tour guide then described the intrusion theory as you describe it. He also added the idea that there may have been a layer of water that the intrusion pushed up through to create those vertical features, like either a layer of ground water or a small lake at the top.

[@owl7093]

Have a look at Mangere Mountain in Auckland New Zealand. It went to blow again but ran out of steam which left the hill in the main crater which could have one of those under it. We still have our mountain, yours has long gone.

[@majirayne1063]

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

[@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-

[@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.

[@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?

[@michaelturner6358]

Have been here, a beautiful and fascinating place.

[@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.

[@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?

[@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?

[@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!

[@edwardhanson3664]

Very interesting, but I wish you had time to talk about that base/pedestal the tower is sitting on.

[@sergiovelazquez1259]

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

[@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.

[@genebohannon8820]

I really like earth science, Dr. Nick Zentner is a rock star!

[@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.

[@johnshoemaker4438]

I did grab a dictionary, but that doesn't change the fact that you could take a moment to explain a term you use over and over.

[@AllensTrains]

I think the explanation for the odd appearance of Devil's Tower is the depth at which the feature was formed. It is likely to have been formed at a greater depth in the Earth's crust - perhaps 10 kilometers. It would have originally have been a volcanic intrusion, but then it was heated and squeezed in the Earth's crust.

[@philipdavis9324]

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

[@davidpotter7484]

there are a couple formations like that in northwest Colorado. Not completely bare though. Lots of lava tubes ive walked through in southeast Idaho.

[@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?

[@user-sg4ei3vv2t]

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.😮

[@jackprier7727]

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

[@John-ir2zf]

I had never noticed the columnar basalt pattern so visible on this monument. Perhaps other photos I had seen were from an angle that didn't highlight the columns.

[@davedavis5809]

I know how it formed....it is intrusive but it's origin is so crazy... You wouldn't believe it!