Fun additional fact about exfoliation weathering: some of it is due to the decompression of the granite itself, which due to forming under kilometers of rock formed under intense pressure. When exposed to atmospheric pressure, the outer layers expand a tiny bit and form shells.
So beautiful: I flew my hang glider from Glacier Point which faces NW toward Half Dome just across the valley. I literally flew THROUGH Yosemite Falls (expert well-experienced pilot here), and then on down the valley, flying just off the face of El Capitan at about 2,000 feet AGL (above ground level) to land in the valley below. One of my most memorable flights, but flying over the Western US and Canada is a great way to experience, marvel, and appreciate geology and the landscape created by it.
@@EthelredHardrede-nz8yv It is a sanctioned launch only at certain times with park approval for advanced rated pilots with insurance and you have to launch prior to 8AM, so yes, permission.
@@BrilliantDesignOnline I once stood at Glacier Point taking photos as the Sun went down. No moon either. Two other guys had stayed there at the same time and then we notice that it was REALLY hard to see and none of us had a flashlight. This was before LED flashlights. One the two said he could just barely make out the path so his friend put his hand on his shoulder and I on his, and we put our lives in his eyes. We were all so glad when we could see the light at the parking lot.
Mr (Dr?) GeologyHub, I have a bachelor's degree in Geology - Chico CSU 1984. In my last semester one of the professors took me aside to explain that because of the oil glut the job market was really bleak. He urged me to consider grad school and to get moving on apps and prepping for the GRE. He knew I was a rock climber and suggested a thesis - "What Causes Pothole Formation on Granite Domes?". Said since I was on granite domes all the time it would be a natural. I could not believe that it would be a serious thesis, but he said "Oh no, plenty of speculation but nothing real has been done" I went out and, of course, could not find a geo job unless I wanted to go to Borneo or the North Slope. I had a pregnant wife, so I took a position in the optics world and had a great career. I do regret not doing geo grad school in a way, but who's to say how it would have gone.
You must have read my father works in petroleum geology , that was his PhD at Stanford . Are you a Indonesian or Malaysian. ? I'm a Filipino like my father.
@@robertotamesis1783 No sir, I didn't. In my selection of classes I don't remember having one specific to petroleum geology. We did have the more basic classes - structure, stratigraphy, invertebrate paleontology, that would be useful in the petroleum world at an entry level. I did take a course in commercial geology but that was very overview. The fact is that a bachelor's degree is a very basic level for geology. Unlike some fields it isn't a terminal degree, it's hardly sufficient for entry level. Practically my only options at that time were grad school, mud logging on the North Slope, or what I did - find a job in another field. I found optical science interesting. I'm just a surfer kid raised in California. Goofed off in school, did some active duty, went back to uni on G.I bill. Where do you live Roberto?
Hello from Oroville. I used to live about 2 hours from Yosemite in the town of Tuolumne. I took so many hikes in the valley etc. So many theories have been posited in the last 100 years. What’s your favorite theory?
@@UTubeQu1che551 Aside from that conference with my professor I've not thought about it much. My immediate thought was that maybe lightning strikes created weaknesses that then developed into a potholes. The prof kind of waved that off saying it's a possibility for initiation. A couple times I've wondered how an investigation would have progressed. I suspect most of the erosion is due to chemical processes from critters - lichens and so forth - finding favorable living conditions in the holes.
It is the closest to where I grew up, and went to four or five others outside of CA, before I went there with a friend at 18. I have been there probably a dozen times (less than a 4 hour drive), but other than the first time, I treasure the memory of my winter visits the most.
This was a particularly good episode as many of us have seen half dome. The fact the crystalline sizing gives us the depth of formation is just terrific information….I’m a physicist but understanding the landscape around us has always fascinated me. I love this channel.
My father got his PhD in Stanford in Geology, so I happened to travel around California and Oregon he would say to me there is lot missing up-cropped , remember seeing dinosaurs footprints on side of a wall , it's like a slabs pushed up side way. Places like Yosemite missing up slabs .
As someone who studied Geology in the Sierra Nevada at a local college, they're much older by roughly 25 million years especially in different sections of the ranges. I am wondering where he's getting this new information from because it hasn't come across publically yet since 2015.
If you think that's crazy, visit Lassen Volcanic National Park and take in all the changes that have happened in that area over the past 10 thousand years.
I was flying into SFO about 10 years ago and we passed just north of Half Dome at about 28,000 ft. Even from that distance and angle, it was instantly recognizable and also didn't look real, somehow. The power of nature and the scale of this planet never cease to amaze me.
Yosemite is spectacular. I last visited in 1993. Hope to be able to return some day. Great concise explanation for the origens of Half Dome by they way.
very very interesting! thanks so much for covering this topic! id love to hear more about the california geolgy and landscape and more about the glaceier carving, why is it so different to say the way the great lakes were formed
The last time I was there was about 14 years ago. I never climbed it but it was cool to see. Especially in the moonlight under the stars. 🌌 Fascinating origin story. 👍✨
I remember when a mini half dome formed in the middle of the Mt St Helens crater about 20 years ago. It crumbled shortly thereafter, and now there lies a different formation.
Another exfoliation note. When you get the thermal expansion and contraction, tension builds up and when the stone layer lets go, it can make a cracking sound as loud as a gunshot. Other times it can be relatively quiet, but if it's quiet and it happens loudly it can scare the bejesus out of you.
I spent a lot of time in Yosemite Valley when I was younger rock climbing. Half Dome was always there. I climbed a few short routes on the lower reaches. A very cool hunk of rock, all right.
I have been to the Mammoth area and Mono lake so many times, yet I have never stepped foot in Yosemite. Maybe some day. I have been able to spot it from the air, though. Which is still pretty breathtaking.
Waring Danger To Shoes! Mono lake is a very salty lake and has a mostly mud shore. That mud is below the encrusted salt. There are a lot of salt encrusted shoes there. If you have seen Clint Eastwood's High Plains Drifter, Mono Lake is the site it was shot on.
I used to work as an adventure tour guide in the U.S. and Canada, and got to go to national parks, state parks, provincial parks, and other amazing places all the time. I never got bored of any of the places I went, but Yosemite NP was hands down my favorite place to visit. Going there made me feel more alive yet simultaneously more peaceful than at any other time in my life. I also lived in Mammoth for a couple years, but oddly never visited Yosemite while I worked up there. So don’t feel guilty about being so close but not going the last few miles when you visited Mammoth and Mono, but I can’t recommend Yosemite highly enough.
I was first made aware of this feature in the documentary about free-climbing by Alex Honnold where you get some very interesting footage of the feature if I remember correctly. The combination of geology, latitude and climate and flora/fauna all make the area beautiful and uplifting.
Alex did a free solo on this rock one afternoon years ago and it was kind of a spur of the moment thing and he wasn't as mentally prepared as he usually was. One of the few times in his climbing career that he kind of froze up for a while and got scared while he got in a bad position going up the rock. he is a one of a kind human being.
Been on top twice - 1982. Started off from the store on the bus to the trail head on a warm thirsty day. Free soloed "Snake Dike", warm and slippery, soloed down the 5.0 route next to the cable route. Got intrigued by the cable route and went up it - found it kind of sketch - soloed back down the 5.0. 6 hours round trip store to top to Mountain Room. Regret not doing it in moonlight, which was popular at the time.
In August we are doing a dirtbike ride, "The Pacific divide ride". Mostly dirt back country roads. From the Canada to the Mexican borders. Through the Cascades then onto the Sierra Nevada range then to the So Cal desert ending a Tecate. 2 weeks with hotels each night. Never done this trip, should be beautiful and challenging.
Lots of good places to kayak around there too. I personally get a blast out of hiking into Tenaya creek and doing the "water slide" or East and West Cherry Creeks. They are both epic. The whole area is dominated by this same kind of dacite.
ok, that was a great explanation for Half Dome and the Sierra Nevada mountains. I'd relaly like to see an explanation of Stone Mountain in Georgia. you can skip the carving if you withs, that's not important to the geology
@@jjMcCartan9686 I found one video where he mentions Stone Mountain North Carolina, not the one in Georgia. Similar process, different time period th-cam.com/video/J81NssZ3xw8/w-d-xo.html
Climbed it twice, once up the dike intrustions on the west side and once up the straight face. You really appreciate the scale when you are attached to the side with a rope. Truly a magnificent area
I probably will never visit, but through your programs I have been able to view these wonderful places and learn how they became as they are now. Thank you for all your hard work.
I have been their many times and never considered if the Sierras are still growing or not. Have they stopped or with the tectonic plates near by, are they still growing?
I climbed Half Dome with my college buddies. We did train to get ready for it. It was challenging at our age and ability. Had a great time, it wasn’t easy. We were sitting at the top near the face of Half Dome kicking back and enjoying the view. That’s when a rock climber came over the face and asked how we were doing...
hiked the rim - some 50 miles of it last year, all of the North and 2/3rds of the South, but sadly skipped the dome, as I was spent as we arrived late in the day. It is a wonderous place, if you get off the valley floor and away from the masses of people. :)
I did a trail hike to the top of Half Dome many years ago. The sheer near-vertical climb, using the cables, was daunting, indeed. Luckily it was a clear day, as on cloudy days, using the cables is not advised due to lightning strikes. What surprised me at the top was the sheer flat size there was; I'd estimate it was about the size of two football fields. That rounded curve section of the mountain . . . I walked out to that section and dared to keep walking outward, noting the gradual increasing downward incline slope. A person has to be careful doing that, as they could literally walk until the slope is so steep that a person could plunge down the mountain.
There are several mountains in the Adirondaks that have the same kind of exfoliation weathering. Most strikingly being Pokamoonshine (Poke-O-Moonshine) mountain in the eastern part of the mountains. Formation was largely the same. A pluton uncapped after a period of uplift and shaped by glacial erosion. Although the rock is mostly granitic gneiss as opposed to granodiorite. The shear rock face that faces the Adirondack Northway (I-87) is a popular rock climbing spot.
It should be noted that based on newer evidence the subduction picture was far more complicated (i.e. the "always Farallon" picture has been falsified) most notably there is pretty strong evidence that the Sierras were an oceanic subduction arc with the then western margin of the North American plate being the one actively subducting at this time until a process known as slab failure occurred due to the increasingly continental affinity of the crust leading to the oceanic slab breaking off from the continent. This leads to a large wave of siliceous melt rising up to fill the gap as the oceanic arc effectively welds to the continental margin. Afterwards the arc polarity reverses subducting the ocean crust to the west of the arc which was the actual Farallon plate. We know the Sierras must have formed though this mechanism because the magmas from slab failure have a distinctive chemical enrichment signature range which differs from that produced by subduction arcs which can be seen today in places like in New Guinea and eastern Indonesia or Taiwan. (Strontium and another element in particular) For more on this see the interview with Robert Hildebrand from Nick Zentner's A to Z Baja BC series it is quite informative. Based on that info I suspect that it helps explain why old fossils aren't found west of death Valley as that likely is where the original NA plate dived down underneath the upper mantle wedge which has been uplifting as it is slowly being sheared off NA.
There's a similar feature in Chile, the Cochamo valley. Some other fun rounded granitic features (albeit without the sheer cliff face) which might be interesting to cover are the Seychelles and the Serra dos Orgaos (along with other parts of the Serra do Mar).
Wow, I can't believe I didn't know that half dome was disk shaped, not round at the back. 🤦 Though I live in California, I haven't been there yet, so I've only seen pictures, and thought it was literally half of a dome. This is so much cooler, plus it's a great example of so many geological processes. 💚✌️😸
While Half Dome is the most impressive granite dome in the area, there are lots of smaller ones in the vicinity that are actually more intact than Half Dome. Most are outside the Yosemite Valley itself, but many still within the park boundaries; the park extends a fair distance beyond the namesake valley.
Hi. A geology question. Something I wonder about in idle moments. In the ancient past like 90 million years ago it is always some "shallow sea". I suppose those environments leave the geological footprint. But there must have been mountains. How big were they? I wonder how many Olympus mons (Mars volcano) size volcanos existed on earth in the long ago.
Basically annealing the hot rocks. This is why it has not fractured into the cubic shapes seen at other sites. Go a little farther north in that same batholith and you see the granite fractured into cubes with almost right angle cleavage.
GeologyHub, would you mind digging into Prof. Nick Zenters 'How Were the Rocky Mountains Formed' and giving your opinion on the evidence? It appears to be quite the revolution in our understanding of how the West Coast up to Alaska and the interior of the U.S. is currently shaped and how certain mount ranges were formed. I think you would enjoy the content, Nick I'd a great lecturer
It's becoming incredibly complicated trying to remember the different stories or theories on the American West. How the Rocky Mountains formed, was the Farallon Plate subducting at a shallow angle, did Mount Stuart used to be at the same latitude as Baja California, and/or what happened to the older Yellowstone super volcanoes? The timelines are hard to keep track on.
Question... Is it possible to have sulfer springs and faults without volcano activity? Theres so much around St Thomas Aquinas University to suggest volcanics and yet its not listed as such. Hot springs, sulfer springs, earthquakes... Im curious as to the possibility of vulcanism there?
Couldn't that intrusion have had a more or less half-dome shape at formation? Take a look at 4096m Mt Kinabalu in Sabah, Malaysia - its peaks / crests have a horseshoe pattern and the external slopes are up to +60° leveling off at the top, on the other hand the inner 'slopes' are extremely vertiginous with 1000m clear falls. It is relatively young in geological terms and still rising at about 5cm / 2" per year.
Evidence of a second magma intrusion after an initial cooling. I cannot cite the work and I have looked online and cannot find another source. I thought for sure the US geological website would reference this. After a short look I could not find it. However I recall reading that part of half dome's story involves evidence of a second magma intrusion after an initial cooling. This second heating prolonged the crystallization process for the pluton that became half dome. This is thought to be the reason for the particularly hard granite in the sheer face that is half dome. I have seen a couple photographs that showed a profile of half dome where there was visual evidence of this secondary intrusion.
I did find one image link illustrating secondary magnet intrusion. North American Wall was my search key. external-content.duckduckgo.com/iu/?u=https%3A%2F%2Ftse1.mm.bing.net%2Fth%3Fid%3DOIP.RCZaKRMDwo9VYInCaAteJgHaFu%26pid%3DApi&f=1&ipt=97001416e7c91c51696ebcd25e1affa3e976dc395049a7a12d53faec0f319bad&ipo=images
Is the Sierra Nevada Mountain Range only 10 million years old or the glaciation of that portion of the Sierra Nevada that old? Which "block" are we talking about? Gold deposits on the West Slope in the Northern and Central Sierra are in river channels on top of bedrock that show a much older North-South orientation. Modern river channels cut through those perpendicularly traveling from East to West. In the Southern Sierra Nevada there was no glaciation and it has its own unique features that are different from the area around Yosemite. I was a Geology Undergrad in the heart of the Sierra Nevada and am wondering when these revelations came about since 2015. Furthermore, volcanic eruptions in the Tahoe Basin closed off the valley known now as Lake Tahoe as the fault block sank occurred roughly 2 Million years ago which could be a topic of another video of yours.
Amateur geo nerd here, all of that sounds fascinating. I'm going to have to check out his videos on the CA volcanoes, etc, to see if he addressed those things. I've always been interested in the geology of the Sierras and was fortunate to be able to Census canvassing north of Yosemite into a lot of forest road areas. Beautiful. Change of topic, but I was wondering what type of work you were doing with your degree. I'm thinking about going back to school. With geology being a big interest, I was wondering if it was mostly resource extraction jobs available in the field, as well as how you like working in the field. Just curious. 🍀✌️😎
@@rngnv4551 Interesting. But California's a good state for agriculture. I've entertained the idea of trying to back to learn Permaculture, soil science, or something involved with sustainability or amelioration. But, those are further outside my experience. However, they still interest me especially since we need to move away from the monocrop model, as well as incorporate remediation and restoration more. Also, there is that thing about getting your hands in the dirt. Hope you're enjoying summer farm life. 🍀✌️😎
Half Dome is one of those once-in-a-lifetime hikes that you should do while you're still young and foolish and carefree. I've done it twice. I'm twice as foolish.
It's a very large piece of the moon. The whole Sierra Nevada range, explaining the massive lithium deposit found last year. Check the surface, you'll find lots of glass. It's a great attempt at explaining, but it makes much more sense that it fell from the sky, which is why it has glass on its surface. Check my slideshows.
Nah, Hephaestus made it to give Zeus a place to sit when he was in California looking for nubile maidens. Zeus complained that Mount Whitney was too pointy. Hurt his butt.
Fun additional fact about exfoliation weathering: some of it is due to the decompression of the granite itself, which due to forming under kilometers of rock formed under intense pressure. When exposed to atmospheric pressure, the outer layers expand a tiny bit and form shells.
This is why geology is fascinating. You can freaking tell how freaking deep the rock formed by the crystalline structures. That's so amazing.
Exfoliation weathering. I learned something new today. Thanks GeologyHub!
True!
I’m 66 years old and I’m sure that my face is undergoing exfoliation weathering. ☹️😉
@@maurasmith-mitsky762 Bald guys would know the feeling too.
Also known as onion or decompression peeling
So beautiful: I flew my hang glider from Glacier Point which faces NW toward Half Dome just across the valley. I literally flew THROUGH Yosemite Falls (expert well-experienced pilot here), and then on down the valley, flying just off the face of El Capitan at about 2,000 feet AGL (above ground level) to land in the valley below. One of my most memorable flights, but flying over the Western US and Canada is a great way to experience, marvel, and appreciate geology and the landscape created by it.
OK did you get arrested or did you get permission?
@@EthelredHardrede-nz8yv It is a sanctioned launch only at certain times with park approval for advanced rated pilots with insurance and you have to launch prior to 8AM, so yes, permission.
@@BrilliantDesignOnline
Thank you. I know people have been arrested on landing.
Prior to 8AM? How uncivilized.
@@BrilliantDesignOnline
I once stood at Glacier Point taking photos as the Sun went down. No moon either. Two other guys had stayed there at the same time and then we notice that it was REALLY hard to see and none of us had a flashlight. This was before LED flashlights.
One the two said he could just barely make out the path so his friend put his hand on his shoulder and I on his, and we put our lives in his eyes.
We were all so glad when we could see the light at the parking lot.
@@EthelredHardrede-nz8yv "Prior to 8AM? How uncivilized." I know, Right? 🙂
Mr (Dr?) GeologyHub,
I have a bachelor's degree in Geology - Chico CSU 1984. In my last semester one of the professors took me aside to explain that because of the oil glut the job market was really bleak. He urged me to consider grad school and to get moving on apps and prepping for the GRE. He knew I was a rock climber and suggested a thesis - "What Causes Pothole Formation on Granite Domes?". Said since I was on granite domes all the time it would be a natural. I could not believe that it would be a serious thesis, but he said "Oh no, plenty of speculation but nothing real has been done"
I went out and, of course, could not find a geo job unless I wanted to go to Borneo or the North Slope. I had a pregnant wife, so I took a position in the optics world and had a great career. I do regret not doing geo grad school in a way, but who's to say how it would have gone.
You must have read my father works in petroleum geology , that was his PhD at Stanford . Are you a Indonesian or Malaysian. ? I'm a Filipino like my father.
@@robertotamesis1783 No sir, I didn't. In my selection of classes I don't remember having one specific to petroleum geology. We did have the more basic classes - structure, stratigraphy, invertebrate paleontology, that would be useful in the petroleum world at an entry level. I did take a course in commercial geology but that was very overview.
The fact is that a bachelor's degree is a very basic level for geology. Unlike some fields it isn't a terminal degree, it's hardly sufficient for entry level. Practically my only options at that time were grad school, mud logging on the North Slope, or what I did - find a job in another field. I found optical science interesting.
I'm just a surfer kid raised in California. Goofed off in school, did some active duty, went back to uni on G.I bill. Where do you live Roberto?
Hello from Oroville. I used to live about 2 hours from Yosemite in the town of Tuolumne. I took so many hikes in the valley etc. So many theories have been posited in the last 100 years. What’s your favorite theory?
@@UTubeQu1che551 Aside from that conference with my professor I've not thought about it much. My immediate thought was that maybe lightning strikes created weaknesses that then developed into a potholes. The prof kind of waved that off saying it's a possibility for initiation. A couple times I've wondered how an investigation would have progressed. I suspect most of the erosion is due to chemical processes from critters - lichens and so forth - finding favorable living conditions in the holes.
I've done the half dome climb twice - definitely a must-do on anybody's bucket list. Assuming you are reasonably fit and able to climb.
Half Dome is such a unique geological feature. Really interesting how it formed.
I love Yosemite NP -- it was the first "famous" NP I visited -- as well as a fun date -- so it is a special park to me. Thank you for this video!
It is the closest to where I grew up, and went to four or five others outside of CA, before I went there with a friend at 18. I have been there probably a dozen times (less than a 4 hour drive), but other than the first time, I treasure the memory of my winter visits the most.
This was a particularly good episode as many of us have seen half dome. The fact the crystalline sizing gives us the depth of formation is just terrific information….I’m a physicist but understanding the landscape around us has always fascinated me. I love this channel.
Thank you! So fun to see something in my relative “backyard” being featured on your show! I have always wondered how Half Dome formed.
took the words right out of my keyboard...I'm 2 hrs away so pretty much 'right in our backyard' too. quite the marvel and great lesson today!
Thank you for that bite sized video explaining the origins of the half dome, very interesting 👍
Saw it from 32,000 feet yesterday!
My father got his PhD in Stanford in Geology, so I happened to travel around California and Oregon he would say to me there is lot missing up-cropped , remember seeing dinosaurs footprints on side of a wall , it's like a slabs pushed up side way. Places like Yosemite missing up slabs .
kinda crazy to think that the sierra nevada mountains are only 10 million years old
As someone who studied Geology in the Sierra Nevada at a local college, they're much older by roughly 25 million years especially in different sections of the ranges. I am wondering where he's getting this new information from because it hasn't come across publically yet since 2015.
Life in the fast lane.
If you think that's crazy, visit Lassen Volcanic National Park and take in all the changes that have happened in that area over the past 10 thousand years.
I was flying into SFO about 10 years ago and we passed just north of Half Dome at about 28,000 ft. Even from that distance and angle, it was instantly recognizable and also didn't look real, somehow. The power of nature and the scale of this planet never cease to amaze me.
One of my favorite places
Climbed to the top of that gorgeous rock back in 2007. Such a great memory!
Yosemite is spectacular. I last visited in 1993. Hope to be able to return some day. Great concise explanation for the origens of Half Dome by they way.
Loved the video. Top notch in every way. More like this please. Have a great weekend.
It is an awesome sight when you first come through the tunnel leading into the Valley of Yosemite and there is Half Dome. This is a great video.
very very interesting! thanks so much for covering this topic! id love to hear more about the california geolgy and landscape and more about the glaceier carving, why is it so different to say the way the great lakes were formed
This is s great channel. I admire your depth and breadth of knowledge in this arena. Thank you
The last time I was there was about 14 years ago. I never climbed it but it was cool to see. Especially in the moonlight under the stars. 🌌
Fascinating origin story. 👍✨
Thanks for all the hard work on these videos
I remember when a mini half dome formed in the middle of the Mt St Helens crater about 20 years ago. It crumbled shortly thereafter, and now there lies a different formation.
Thanks.
Another exfoliation note. When you get the thermal expansion and contraction, tension builds up and when the stone layer lets go, it can make a cracking sound as loud as a gunshot. Other times it can be relatively quiet, but if it's quiet and it happens loudly it can scare the bejesus out of you.
I spent a lot of time in Yosemite Valley when I was younger rock climbing. Half Dome was always there. I climbed a few short routes on the lower reaches. A very cool hunk of rock, all right.
When i went to Yosemite valley coulle years back, seeing half done was amazing as looking at it from the distance was just breathe taking
I have been to the Mammoth area and Mono lake so many times, yet I have never stepped foot in Yosemite. Maybe some day. I have been able to spot it from the air, though. Which is still pretty breathtaking.
Waring Danger To Shoes! Mono lake is a very salty lake and has a mostly mud shore. That mud is below the encrusted salt. There are a lot of salt encrusted shoes there.
If you have seen Clint Eastwood's High Plains Drifter, Mono Lake is the site it was shot on.
I used to work as an adventure tour guide in the U.S. and Canada, and got to go to national parks, state parks, provincial parks, and other amazing places all the time. I never got bored of any of the places I went, but Yosemite NP was hands down my favorite place to visit. Going there made me feel more alive yet simultaneously more peaceful than at any other time in my life. I also lived in Mammoth for a couple years, but oddly never visited Yosemite while I worked up there. So don’t feel guilty about being so close but not going the last few miles when you visited Mammoth and Mono, but I can’t recommend Yosemite highly enough.
Watching this from Yosemite Valley. Fantastic video!
I was first made aware of this feature in the documentary about free-climbing by Alex Honnold where you get some very interesting footage of the feature if I remember correctly. The combination of geology, latitude and climate and flora/fauna all make the area beautiful and uplifting.
Alex did a free solo on this rock one afternoon years ago and it was kind of a spur of the moment thing and he wasn't as mentally prepared as he usually was. One of the few times in his climbing career that he kind of froze up for a while and got scared while he got in a bad position going up the rock. he is a one of a kind human being.
Been on top twice - 1982. Started off from the store on the bus to the trail head on a warm thirsty day. Free soloed "Snake Dike", warm and slippery, soloed down the 5.0 route next to the cable route. Got intrigued by the cable route and went up it - found it kind of sketch - soloed back down the 5.0. 6 hours round trip store to top to Mountain Room. Regret not doing it in moonlight, which was popular at the time.
In August we are doing a dirtbike ride, "The Pacific divide ride". Mostly dirt back country roads. From the Canada to the Mexican borders. Through the Cascades then onto the Sierra Nevada range then to the So Cal desert ending a Tecate. 2 weeks with hotels each night. Never done this trip, should be beautiful and challenging.
The NorCal BDR looks nice too if you're into doing some moto camping along the way.
@@fallinginthed33p Yes, my friend and I are planning that one too. Bought the map just need to download the GPS route and give a donation.
Lots of good places to kayak around there too. I personally get a blast out of hiking into Tenaya creek and doing the "water slide" or East and West Cherry Creeks. They are both epic. The whole area is dominated by this same kind of dacite.
ok, that was a great explanation for Half Dome and the Sierra Nevada mountains. I'd relaly like to see an explanation of Stone Mountain in Georgia. you can skip the carving if you withs, that's not important to the geology
He's done stone mountain before .
@@jjMcCartan9686 I found one video where he mentions Stone Mountain North Carolina, not the one in Georgia. Similar process, different time period
th-cam.com/video/J81NssZ3xw8/w-d-xo.html
Panola and Arabia too.
Very nice work, Timothy. John Muir talked about Half Dome, one of my
favorite crusty explorers.
Climbed it twice, once up the dike intrustions on the west side and once up the straight face. You really appreciate the scale when you are attached to the side with a rope. Truly a magnificent area
You can go back to see it again , hasn't eroded yet.
Interesting. Watching fromt the Philippines.
I shouldn’t need to even remark on this, but…
THANK YOU for narrating this in a normal, non-AI voice! Great information.
Very interesting! Thanks Timothy!
Excellent!
I probably will never visit, but through your programs I have been able to view these wonderful places and learn how they became as they are now.
Thank you for all your hard work.
I have been their many times and never considered if the Sierras are still growing or not. Have they stopped or with the tectonic plates near by, are they still growing?
Could you make a vid about desserts on greek islands
I climbed Half Dome with my college buddies. We did train to get ready for it. It was challenging at our age and ability. Had a great time, it wasn’t easy. We were sitting at the top near the face of Half Dome kicking back and enjoying the view. That’s when a rock climber came over the face and asked how we were doing...
Information next level... Awesome.
Been up there. That was a good workout. Took me and my son about nine hours round trip. Beautiful view.
hiked the rim - some 50 miles of it last year, all of the North and 2/3rds of the South, but sadly skipped the dome, as I was spent as we arrived late in the day. It is a wonderous place, if you get off the valley floor and away from the masses of people. :)
I did a trail hike to the top of Half Dome many years ago.
The sheer near-vertical climb, using the cables, was daunting, indeed. Luckily it was a clear day, as on cloudy days, using the cables is not advised due to lightning strikes.
What surprised me at the top was the sheer flat size there was; I'd estimate it was about the size of two football fields.
That rounded curve section of the mountain . . . I walked out to that section and dared to keep walking outward, noting the gradual increasing downward incline slope. A person has to be careful doing that, as they could literally walk until the slope is so steep that a person could plunge down the mountain.
There are several mountains in the Adirondaks that have the same kind of exfoliation weathering. Most strikingly being Pokamoonshine (Poke-O-Moonshine) mountain in the eastern part of the mountains. Formation was largely the same. A pluton uncapped after a period of uplift and shaped by glacial erosion. Although the rock is mostly granitic gneiss as opposed to granodiorite. The shear rock face that faces the Adirondack Northway (I-87) is a popular rock climbing spot.
You helped us learn something new,(type of rock tells you at what depth it cooled), thank you.
Fascinating, thank you
Fascinating.
I have seen a lot of large quartz crystals in Sierra's granite - some of them more than 2" long. Very interesting.
Thank you
Thanks as always, Geology Hub! I hope you enjoyed your visit to Half Dome!
I think it would also be interesting to make a video about the formation of the Dolomites and the Torres del Paine
Really interesting!
It should be noted that based on newer evidence the subduction picture was far more complicated (i.e. the "always Farallon" picture has been falsified) most notably there is pretty strong evidence that the Sierras were an oceanic subduction arc with the then western margin of the North American plate being the one actively subducting at this time until a process known as slab failure occurred due to the increasingly continental affinity of the crust leading to the oceanic slab breaking off from the continent. This leads to a large wave of siliceous melt rising up to fill the gap as the oceanic arc effectively welds to the continental margin. Afterwards the arc polarity reverses subducting the ocean crust to the west of the arc which was the actual Farallon plate.
We know the Sierras must have formed though this mechanism because the magmas from slab failure have a distinctive chemical enrichment signature range which differs from that produced by subduction arcs which can be seen today in places like in New Guinea and eastern Indonesia or Taiwan. (Strontium and another element in particular)
For more on this see the interview with Robert Hildebrand from Nick Zentner's A to Z Baja BC series it is quite informative.
Based on that info I suspect that it helps explain why old fossils aren't found west of death Valley as that likely is where the original NA plate dived down underneath the upper mantle wedge which has been uplifting as it is slowly being sheared off NA.
It's well worth the trip.
There's a similar feature in Chile, the Cochamo valley. Some other fun rounded granitic features (albeit without the sheer cliff face) which might be interesting to cover are the Seychelles and the Serra dos Orgaos (along with other parts of the Serra do Mar).
Wow, I can't believe I didn't know that half dome was disk shaped, not round at the back. 🤦
Though I live in California, I haven't been there yet, so I've only seen pictures, and thought it was literally half of a dome.
This is so much cooler, plus it's a great example of so many geological processes. 💚✌️😸
That was well done!
While Half Dome is the most impressive granite dome in the area, there are lots of smaller ones in the vicinity that are actually more intact than Half Dome. Most are outside the Yosemite Valley itself, but many still within the park boundaries; the park extends a fair distance beyond the namesake valley.
Funny, over in Riverside, CA, we have a natural formation that looks a lot like it. And some amazing cliffs, one in Shadow Rock Park.
So odd. I was in Yosemite June 9/10th and was staring at this thing. Now I know what I was staring at! Haha
Hi.
A geology question. Something I wonder about in idle moments.
In the ancient past like 90 million years ago it is always some "shallow sea". I suppose those environments leave the geological footprint. But there must have been mountains. How big were they? I wonder how many Olympus mons (Mars volcano) size volcanos existed on earth in the long ago.
"But there must have been mountains." - Yes, for example the Appalachians are what's left of a major orogeny from the formation of supercontinents.
Is it me or is the video jumpy in the beginning?
Good content 👌 😊
Very interesting
It must be seen to be believed. The whole area is almost laughably beautiful.
Can you make a video on stone mountain in Georiga?? Thanks!
Basically annealing the hot rocks. This is why it has not fractured into the cubic shapes seen at other sites. Go a little farther north in that same batholith and you see the granite fractured into cubes with almost right angle cleavage.
GeologyHub, would you mind digging into Prof. Nick Zenters 'How Were the Rocky Mountains Formed' and giving your opinion on the evidence? It appears to be quite the revolution in our understanding of how the West Coast up to Alaska and the interior of the U.S. is currently shaped and how certain mount ranges were formed. I think you would enjoy the content, Nick I'd a great lecturer
Another cause of the exfoliation is the release of pressure remaining from when the granodiorite was several miles down.
Hey Geology Hub, can you make a video about Enchanted Rock in Texas?
It's becoming incredibly complicated trying to remember the different stories or theories on the American West. How the Rocky Mountains formed, was the Farallon Plate subducting at a shallow angle, did Mount Stuart used to be at the same latitude as Baja California, and/or what happened to the older Yellowstone super volcanoes? The timelines are hard to keep track on.
Stone Mountain in Northern Georgia was formed the same way.
Like the swirled top of an ice cream cone, you could just imagine “worlds in collision” over Yosemite
Is this similar to Cathedral ledge, Whitehorse Ledge in North Conway NH??
Yes. Similar origins.
@@EatsLikeADuck I am from North Conway NH and knew about the volcanology of the area but was curious about the plutonic stuff, thx
Theres quite a few much smaller formations through Calis central coast, especially the Morro Bay area.
Will you discuss the Wyoming landslide
I would love to experience Half Dome. Perhaps just hike up to the top though, lol.
Maybe I missed this part, but can you explain what happened to the missing half of the dome?
"Giant pieces are falling off, but I recommend you go and see it."
Question... Is it possible to have sulfer springs and faults without volcano activity?
Theres so much around St Thomas Aquinas University to suggest volcanics and yet its not listed as such. Hot springs, sulfer springs, earthquakes... Im curious as to the possibility of vulcanism there?
Couldn't that intrusion have had a more or less half-dome shape at formation? Take a look at 4096m Mt Kinabalu in Sabah, Malaysia - its peaks / crests have a horseshoe pattern and the external slopes are up to +60° leveling off at the top, on the other hand the inner 'slopes' are extremely vertiginous with 1000m clear falls. It is relatively young in geological terms and still rising at about 5cm / 2" per year.
Evidence of a second magma intrusion after an initial cooling.
I cannot cite the work and I have looked online and cannot find another source. I thought for sure the US geological website would reference this. After a short look I could not find it.
However I recall reading that part of half dome's story involves evidence of a second magma intrusion after an initial cooling. This second heating prolonged the crystallization process for the pluton that became half dome. This is thought to be the reason for the particularly hard granite in the sheer face that is half dome. I have seen a couple photographs that showed a profile of half dome where there was visual evidence of this secondary intrusion.
I did find one image link illustrating secondary magnet intrusion.
North American Wall was my search key.
external-content.duckduckgo.com/iu/?u=https%3A%2F%2Ftse1.mm.bing.net%2Fth%3Fid%3DOIP.RCZaKRMDwo9VYInCaAteJgHaFu%26pid%3DApi&f=1&ipt=97001416e7c91c51696ebcd25e1affa3e976dc395049a7a12d53faec0f319bad&ipo=images
Is the Sierra Nevada Mountain Range only 10 million years old or the glaciation of that portion of the Sierra Nevada that old? Which "block" are we talking about? Gold deposits on the West Slope in the Northern and Central Sierra are in river channels on top of bedrock that show a much older North-South orientation. Modern river channels cut through those perpendicularly traveling from East to West. In the Southern Sierra Nevada there was no glaciation and it has its own unique features that are different from the area around Yosemite. I was a Geology Undergrad in the heart of the Sierra Nevada and am wondering when these revelations came about since 2015. Furthermore, volcanic eruptions in the Tahoe Basin closed off the valley known now as Lake Tahoe as the fault block sank occurred roughly 2 Million years ago which could be a topic of another video of yours.
Amateur geo nerd here, all of that sounds fascinating. I'm going to have to check out his videos on the CA volcanoes, etc, to see if he addressed those things.
I've always been interested in the geology of the Sierras and was fortunate to be able to Census canvassing north of Yosemite into a lot of forest road areas. Beautiful.
Change of topic, but I was wondering what type of work you were doing with your degree. I'm thinking about going back to school. With geology being a big interest, I was wondering if it was mostly resource extraction jobs available in the field, as well as how you like working in the field. Just curious. 🍀✌️😎
@@erinmac4750 I went into Mineralogy eventually but left the industry to get my hands into the dirt with Agriculture.
@@rngnv4551 Interesting. But California's a good state for agriculture. I've entertained the idea of trying to back to learn Permaculture, soil science, or something involved with sustainability or amelioration. But, those are further outside my experience. However, they still interest me especially since we need to move away from the monocrop model, as well as incorporate remediation and restoration more.
Also, there is that thing about getting your hands in the dirt. Hope you're enjoying summer farm life. 🍀✌️😎
4:29 Is that a ladder? My legs start shaking just looking at it lol.
Half dome sits adjacent to a lesser known oddity in the vicinity, known as chrome dome.
Half Dome is one of those once-in-a-lifetime hikes that you should do while you're still young and foolish and carefree. I've done it twice. I'm twice as foolish.
It's a very large piece of the moon. The whole Sierra Nevada range, explaining the massive lithium deposit found last year. Check the surface, you'll find lots of glass. It's a great attempt at explaining, but it makes much more sense that it fell from the sky, which is why it has glass on its surface. Check my slideshows.
Hard to believe that at one time half dome was six miles underground.
Is granodiorite the rarest of those three types of rocks mentioned? At least to see on the surface?
I know nothing of geology…
No its very common in the Sierra Nevada.
@@adamc1966 Apologies, I meant outside of the Sierra Nevada range. Should've clarified in my comment, but it was late at night...
Nah, Hephaestus made it to give Zeus a place to sit when he was in California looking for nubile maidens. Zeus complained that Mount Whitney was too pointy. Hurt his butt.
It's not half a dome, it's half a cheese.
Silly
@@GeologyHub Guilty as charged 😊
@@GeologyHub😂
🧀
Lmfao
I’m guessing it’s the same or similar with Stone Mountain in Georgia
If you want to see a cool video watch California Gold with Huel Howser. He climbs to the top.