Whole Mountain of VOLCANIC GLASS! Explore the geology of Glass Mountain, California

Ғылым және технология

Geology professor Shawn Willsey explores the exceptional geology of Glass Mountain, part of the Medicine Lake volcano in northern California. Learn how obsidian and pumice are related and then investigate the spectacular textures and forms of these rocks.
00:00 intro and rock quiz
01:58 location
02:10 explore Glass Mountain
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Shawn Willsey
College of Southern Idaho
315 Falls Avenue
Twin Falls, ID 83303

Пікірлер: 257

  • @shawnwillsey
    @shawnwillsey9 ай бұрын

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

  • @vernowen2083
    @vernowen20839 ай бұрын

    Three years ago, I was exploring with my metal detector, around my Arizona campsite, along a wash, when I came across a bunch of obsidian flakes. Obviously, someone had been knapping at this site and recent flash flooding had exposed the shards of obsidian. What surprised me the most was that much of the obsidian was obviously not native to Arizona and after reporting the area to local authorities, who excavated the site, it was reported the obsidian was from New Berry crater, in Oregon.

  • @williamchamberlain2263

    @williamchamberlain2263

    9 ай бұрын

    Long distance trade can take quality materials a long way. _If_ i remember right, the neolithic trade across Europe and Asia Minor moved amber and lapis a long way

  • @muzikhed

    @muzikhed

    9 ай бұрын

    And mountain people used to interchange obsidian and chert etc for shells and the like from coastal tribes.

  • @baneverything5580

    @baneverything5580

    9 ай бұрын

    I`ve found arrowheads here in Louisiana made of stone that we don`t have in the state. I wish I could have studied geology but mental problems basically crippled me in my teens and I never received treatment. But there are no treatments...just dangerous, sedating medications that make things worse and damage the brain and body. I saw an open box deal on a Minelab Vanquish 340 metal detector for only 170 and immediately ordered it. I found about 30 coins in my very trashy yard in about two hours with it. What amazed me about it is how it can accurately identify a quarter right beside a 6 inch rusty nail.

  • @gwynnfarrell1856
    @gwynnfarrell18569 ай бұрын

    The layers of obsidian and pumice are fascinating! I didn't know that the two could be found together like that. Amazing!

  • @YewtBoot

    @YewtBoot

    9 ай бұрын

    Agree. A good example to illustrate the connectedness.

  • @coachhannah2403

    @coachhannah2403

    9 ай бұрын

    Yup! In the SAME ROCK! A creek runs nearby. I knocked a bit of shore into the water by stepping too close to an undercut, and the gravel floated away downstream... 😁 That was at Obsidian Dome near Yosemite.

  • @williamchamberlain2263

    @williamchamberlain2263

    9 ай бұрын

    ​@@coachhannah2403pumice is weird as heck

  • @garypasko5314
    @garypasko53149 ай бұрын

    So in the summer of 1990, I worked for the NPS in Lava Beds NM looking for Bald Eagle barf. The bald eagle was being delisted from the endangered species list and they were creating a management plan. Anyway, on a sunny day, you could look to the south and see Glass Mountain glittering in the sunlight. Really cool!

  • @dave9351

    @dave9351

    9 ай бұрын

    Different Glass Mountain... California is a long way from New Mexico Bald Eagle Barf ????

  • @tomchambers1961

    @tomchambers1961

    9 ай бұрын

    I took that as National Monument Dave.....all fascinating!@@dave9351

  • @jamessmelcer616

    @jamessmelcer616

    9 ай бұрын

    The N M is, National Monument not New Mexico. 🙂

  • @garypasko5314

    @garypasko5314

    9 ай бұрын

    @@dave9351 NM is National Monument. They're actually called castings. Many birds of prey cannot digest certain parts of the things they eat. So they regurgitate, or cast it to the ground. However, nobody ever knew what castings were, but everybody knows what barf is. So just called it barf.

  • @mindysdad3110
    @mindysdad31109 ай бұрын

    Thanks to your classroom videos I was able to ID both rocks!

  • @levibranch7318
    @levibranch73189 ай бұрын

    What are the odds? I am from Utah and have been watching all of your videos enjoying all of them for the last two months. Trying to teach my kids about rocks and where and how they were made while driving Utah and Idaho. (Failing) Funny enough last night we drove to Sacramento though Nevada and up over Reno and Lake Tahoe. While on that drive my 9 year old asked what type all the rockets were we were seeing. My reply was oh man I haven’t watched one of Shawn’s videos of California yet too bad he isn’t in California with us. What are the odds? My 9 yr old daughter struggles with school but Volcanos and Mountains excite her and open a flood gate of hundreds of questions my wife and I try to google or learn from Shawn. Keep it up. Great content.

  • @Anne5440_

    @Anne5440_

    9 ай бұрын

    Get her a children's book on Volcanos. Try the library in your area. Have the librarian help find books in the children's section. Then when she picks her favorite volcano books you will want to buy those. She will want her own copies. In future she may want to get books that are at older reading levels. Of course keep taking her to mountains and watching Shawn's videos. I discovered volcanos at age 5. I'm 75 now and am as passionate about volcanos today as I was at 5 years old. You're doing the right thing to encourage her. Oh also rock and mineral guides might help answering questions.

  • @nanasloves

    @nanasloves

    9 ай бұрын

    Go to craters of the moon! Later in the year when it’s not so dang hot. I loved walking in the lava tunnels.

  • @Anne5440_

    @Anne5440_

    9 ай бұрын

    @garyb6219 that you. I agree Craters of the Moon, could be a nice vacation.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    I agree with all the replies here. Best advice is to foster her interests and love of learning as best you can while you have this precious window. Once they turn 12, 13, etc. they change and lose or "bury" these interests through the adolescent years. Books, videos, museums, field trips. If you are in southern Idaho sometime, have her stop by and I'll chat with her and show her some fun rock samples. Keep encouraging her to observe the natural world, verbalize or record those observations, and ask questions. Science starts there.

  • @daphnewilson7966

    @daphnewilson7966

    9 ай бұрын

    Sacramento to Reno: main answer: Granite! The great formations in Yosemite: granite, cut by glaciers. Over Donner Pass and down along the Truckee River, a mountain of volcanic cinders apparently being mined (?) and the dramatic rhyolite canyon down to Verdi. God Bless curiosity!

  • @markrothenbuhler6232
    @markrothenbuhler62329 ай бұрын

    No kidding Glass Mountain! It sounds like you are walking on broken glass the whole time. Great video!

  • @jackprier7727
    @jackprier77279 ай бұрын

    Thanks for showing all these igneous relationships basalt, scoria, then gas-glass and ooze-glass. Also, the footsteps sound extra-crunchy.

  • @pattilemonhouse7911

    @pattilemonhouse7911

    12 күн бұрын

    "extra crunchy"🤭

  • @IndridCool54
    @IndridCool549 ай бұрын

    Very cool! And so young. I wonder about indigenous peoples recollections of this. There must be stories. 👍🏼

  • @DMLand

    @DMLand

    9 ай бұрын

    The whole time prof. Willsey as walking around on that mountain of broken glass, I couldn't help but remember Jaime de Angulo's "Indian Tales" (1953) and the "Flint people," described as living "at the foot of Black Glass Mountain … made entirely of black obsidian." Indian Tales tells ancient origin stories of the peoples of the Pacific coast. Although I can't find it in my copy of the book, I seem to remember that the Flint People were described as making the sound we hear throughout this video as they moved and talked.

  • @R.E.A.P
    @R.E.A.P9 ай бұрын

    Newberry volcano is an amazing place to see obsidian. Thanks for another great video.

  • @swirvinbirds1971

    @swirvinbirds1971

    9 ай бұрын

    Before he even mentioned it I was seeing the similarities to Newberry.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Look for the Newberry video in coming weeks.

  • @R.E.A.P

    @R.E.A.P

    9 ай бұрын

    @shawnwillsey Thanks for your reply, can't wait to see it.

  • @hanspeterplanzer1837
    @hanspeterplanzer18379 ай бұрын

    Thank you. From switzerland. 🙂

  • @carriker54
    @carriker549 ай бұрын

    There is a hill @640’ called Glass Mountain in St. Helena (Napa Valley). There is Obsidian but it seems that it also shows trace “rhyolite ash” and “perlite”. Quite an anomaly. This is attributed to the high silica content in the Sonoma Volcanics field. There are several “Glass Mtns.” In California. The one I plan to visit first is near Mono Lake in the Long Valley Caldera (Owen’s Valley). Mono Lake has Tufa’s. Check them out. Thank you for the great video.

  • @kimburke3189
    @kimburke31899 ай бұрын

    I grew up camping at Medicine Lake. It was so cool exploring the glass mountain. we found arrowheads and the imprints of animals caught in the glass flow! we carried some obsidian rocks home to San Jose for my parent's rock garden. That was back in the 1960s. Thanks for reminding me of good times!

  • @skyedog24
    @skyedog249 ай бұрын

    Well I got one out of two I know obsidian well my grandparents were RockHounds you would think I would have guessed pumice as well . The folds were the most amazing part of this video.

  • @briane173

    @briane173

    9 ай бұрын

    Indeed. I'm blown away by the layering of two such different rock types that _form_ so differently. The pasty nature of the flow promotes all the folding, but what's amazing to me is that the two layers are able to hold their composition even while in contact with each other.

  • @jamessmelcer616
    @jamessmelcer6169 ай бұрын

    Glad to see you in my neck of the woods Shawn! I am fourth generation Siskiyou and Modoc county native.( not Indian) In the summer of 1970 I worked on a fire crew at Lava Beds National Monument. In my free time I explored the area extensively, plus I hunted mule deer in this area. It is truly fascinating and beautiful,lots of lava tubes etc. Great post Shawn keep em coming!👍👏❤️😁

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Lots more from your area coming soon. I did several videos at lava beds.

  • @pattilemonhouse7911
    @pattilemonhouse791112 күн бұрын

    I was looking at that very steep incline, which can be challenging enough, but you're talking at the same time. Geology keeps you fit! 👍

  • @davidk7324
    @davidk73249 ай бұрын

    Remarkable is right. Google videos of taffy pulling machines. I remember seeing them at the Idaho State Fair when I was a kid in the 60s. That's the metaphor that immediately sprung to my mind.

  • @hestheMaster
    @hestheMaster9 ай бұрын

    Coolest looking rocks ever. So much differences in the types making up the layers. Weather changes have played havoc in the cooled rock , cracking everything up, which actually came out of the Earth surface slowly about 950 years ago. Nice to actually see this on video Shawn. There are many small volcanoes that make up the area to the north and yet to see those. Plus the shield volcano that is Medicine Lake. Recommend very sturdy footwear here!

  • @bottomup12
    @bottomup129 ай бұрын

    Nailed the quiz thanks to your rock identification videos. 🤓 What a cool place that was once very hot.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Solid work. Well done.

  • @henrywelch7900
    @henrywelch79009 ай бұрын

    Wife and I went to Newberry earlier this summer, when she sees this video we may be loading the car for another road trip

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Look for a Newberry video in the coming weeks.

  • @LanceHall
    @LanceHall9 ай бұрын

    Cool place.

  • @jerrywills
    @jerrywills8 ай бұрын

    Fantastic! Really enjoy all you do! This one was, for me, terrific!

  • @meredithfrench5258
    @meredithfrench52589 ай бұрын

    What a great location to illustrate both. Wish I was still teaching. Thanks

  • @mickie7873
    @mickie78739 ай бұрын

    Fassninating to see the folds of lava that had been flowing......and the inserts of Obsidian ot lava that had cooled and was exposed during the flow episode. Thank you for sharing on film this site!!

  • @ruthiemay423
    @ruthiemay4239 ай бұрын

    Instead of toothpaste, it reminds me of watching a taffy machine. What a fascinating place. I would be inclined to have a desire to take home a truckload... ❤❤❤

  • @SkepticalRaptor
    @SkepticalRaptor9 ай бұрын

    I thought you were close to me, since I’m not far from Glass Mountain, but my Glass Mountain is in Mono County and is part of the Long Valley Caldera. I didn’t know there was another Glass Mountain in California. Anyway, very interesting volcano.

  • @oscarmedina1303
    @oscarmedina13039 күн бұрын

    Thanks Shawn! Very enjoyable video. Now on my list of places to visit.

  • @lornaperryman489
    @lornaperryman4899 ай бұрын

    What a great lesson. First time I ran into your channel, won't be the last.😊

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Welcome aboard! Enjoy the existing videos. Lots of choices.

  • @GrandmasterBBC
    @GrandmasterBBC9 ай бұрын

    You're in the field video tours are amazing. What an incredible geologic playground.

  • @Arcticfox7
    @Arcticfox7Ай бұрын

    Absolutely fascinating 😮

  • @dontask8979
    @dontask89799 ай бұрын

    The folded layers are awesome

  • @nathanmarchant2175
    @nathanmarchant21759 ай бұрын

    Great footage & comentary! Thank you for sharing your knowledge. I'm from Utah & have some nice pieces of obsidian in my front yard My mother used to take us to Glass Mountain when we would go to Medicine Lake

  • @Rachel.4644
    @Rachel.46449 ай бұрын

    The folds are just crazy....so clearly defined by the obsidian and pumice! Spectacular, Shawn. It looks sharp and tricky.

  • @quantumcat7673
    @quantumcat76739 ай бұрын

    The little test was easy. I'm ready for the final exam.

  • @johnschulte347
    @johnschulte3479 ай бұрын

    Thanks!

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Thanks for your kind donation.

  • @kristinh9140
    @kristinh91409 ай бұрын

    Very cool! Thank you for sharing.

  • @surendersingal2192
    @surendersingal21929 ай бұрын

    Thank you sir for showing this glass mountain. Looked rock for Fence building but there seems more to it glass n floatabioity. Good day jussojuan

  • @ricksanderson4640
    @ricksanderson46409 ай бұрын

    Really interesting location, had no idea about the relationship between obsidian and pumice. Thanks for the work you do, really enjoy it

  • @gi_nattak
    @gi_nattak9 ай бұрын

    When I was very young, back in the early 90s, my family and I stopped by there, as we were on our way to some property we owned or maybe still own out in Modoc. We and a bunch of other people took a bunch of large pieces, even though that was not permitted. We still have them in our front yard to this day!

  • @kisheacox8147
    @kisheacox81479 ай бұрын

    Obsidian. Pumice. Aced it! Woohoo!

  • @muzikhed
    @muzikhed9 ай бұрын

    Truely fantastic. I'd never seen such close contact with Pumise and Obsidian. Amazing folding of those layers of Obsidian. Fascinating. Nice find Shawn !

  • @3xHermes
    @3xHermes2 ай бұрын

    Surreal landscape, sounds like you were walking on Glass.

  • @GasketManzrevenge
    @GasketManzrevenge9 ай бұрын

    A suggestion to those who decide to go.. boots, thicker jeans/shirt, and gloves are a must have when hiking over that pile of glass. It's an awesome place to visit with lots to see. In retrospect, it's time to go back.. been a while. Plenty of lava tubes to explore at the park north of Glass Mtn. Go get your hike on!! (pack a lunch)

  • @angusmorrison9433
    @angusmorrison94339 ай бұрын

    I'd love to have that initial piece of obsidian for my coffee table, and a few good pieces of pumice in my bath!

  • @lawrencet83
    @lawrencet839 ай бұрын

    Are you going to visit Mt. Lassen? I used to camp there and climbed to the peak. It's amazing to hike on a potentially active volcano in California. I live in Houston now where there is no volcanoes, and no earthquakes. Just hot temperatures and hurricanes.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Yes, I visited Lassen on the same trip but unfortunately, was there the day the remnants of Hurricane Hilary hit the area so it was socked in and rainy. I did do two videos though that I will likely post in the coming weeks.

  • @sharonseal9150
    @sharonseal91509 ай бұрын

    Thanks as always for an entertaining and informative geology video - love that you take us to so many places! One question I had on the obsidian - does each flow have a distinct enough chemical signature that it can be used to associate artifacts made from it?

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Yes, trace elements in obsidian can often be traced back to their original source.

  • @michaelnancyamsden7410
    @michaelnancyamsden74109 ай бұрын

    It is amazing to see the pumice so closely intertwined with obsidian. Never would have thunk it. Thanks for svrambling for me.

  • @aubreyleonae4108
    @aubreyleonae41089 ай бұрын

    I was privileged to study three years under a Dartmouth trained geologist in high school, at Henley HS in Klamath . He had a pregnant wife as he began his doctoral dissertation and took a job with USGS, never getting back to his PhD. I majored in geology at OSU, but paused to get married and never made it back. Oye vey. Love your channel so far. Thanks for your work.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Cool story. Thanks for watching. Glad you can get back to your geo roots.

  • @Eyebagdude

    @Eyebagdude

    9 ай бұрын

    I am a Henley graduate

  • @patriciaroysdon9540
    @patriciaroysdon95409 ай бұрын

    Absolutely fascinating!

  • @noel3422
    @noel34222 ай бұрын

    Hello Shawn, been there a few times back in the 90's, back then there was a road where you could drive up to the top in your car, giant chunks of obsidian on top.

  • @rudyrod100
    @rudyrod1009 ай бұрын

    Your videos are bad ass! Thanks.

  • @craighoover1495
    @craighoover14959 ай бұрын

    I will always know pumice when I see it for I used to have to scrub a big flat grill in a commercial kitchen with it at the end of every day. It was remarkably consistent in texture and it would wear away with use. I had never thought until this moment how that it could be that that texture could be so consistent but perhaps in nature there are locations where it is uniform like that and it is mined. Perhaps it is artificially produced?

  • @dudeonbike800
    @dudeonbike8008 ай бұрын

    1) Obsidian 2) Pumice I honestly didn't cheat. I suck at naming rocks. "Rocks for Jocks" class was hard! Wow, wonderful video and geology lesson on the area. Spent early childhood summers at Lassen. So cool to learn more about the area. Thank you.

  • @MrStillracin
    @MrStillracin9 ай бұрын

    Awesome

  • @genier7829
    @genier78299 ай бұрын

    This was great- I visited this place more than 50 years ago as a young girl and have wanted to return some day.

  • @valoriel4464
    @valoriel44649 ай бұрын

    Grt geo-adventure. Thx Prof ✌🏻

  • @juliesiff1
    @juliesiff19 ай бұрын

    Thanks! That was AWESOME 😮❤

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Thanks for your kind donation. Glad you enjoyed this amazing place.

  • @johndefalque5061
    @johndefalque50613 ай бұрын

    I travelled through all of CA except for San Diego, 42 yrs ago. I miss it. Didn't get to see La Brea. Lived in BC for 30 yrs. Now live in Quebec. Want to get a motorcyle and take up camping.

  • @EloiseBarker-py9fh
    @EloiseBarker-py9fh9 ай бұрын

    WOW Damn that is so cool. Thanks for showing all the beauty of geology.

  • @petacarney9848
    @petacarney98489 ай бұрын

    Thank you Shawn - love your videos 😀

  • @AhJodie
    @AhJodie9 ай бұрын

    Fantastic video, thank you!

  • @johnschulte347
    @johnschulte3479 ай бұрын

    Appreciate your work.

  • @JAllenIsaac
    @JAllenIsaac9 ай бұрын

    Fascinating area and great content!

  • @briane173
    @briane1739 ай бұрын

    Wow, Glass Mountain looks even more awesome than Big Obsidian Flow at Newberry! That's worth taking a drive. BTW, Shawn, sorry I couldn't make it last week. One of the questions I was going to ask if we'd been able to meet up at Newberry was about Big Obsidian Flow and Glass Mountain and just about anywhere that forms this amazing obsidian: Since it requires RAPID cooling in order for obsidian to form without mineralizing, can some of that rapid cooling be attributed to the environmental or climate factors in place at the time it erupts? I've noticed that these obsidian flows occur at pretty high elevation, where at times it can get bitter cold or even glaciers are present; do you see any evidence of these pasty flows taking place either under snow or glaciers? Or such low air temps that it impacts rapid cooling of these flows? I can see no evidence of these flows forming as tuyas, but I can see where a cold enough climatic environment might be enough to cool these flows almost like a fast-paced freeze-dry process. Your thoughts?

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    No worries Brian. The air or ambient temperature plays little to no role in cooling of lava. For instance, the colder temps of the mountains or a glacier. For example, if you have felsic magma that is 1,500 F, then it doesn't really matter if its a balmy 80 F at the surface or 20 F and snowing. This 60 degree difference is miniscule compared to the temp of the magma. Volcanoes belch out lava and other stuff and gradually build up a higher topographic structure so it makes sense that many of these flows are at higher elevations.

  • @cw7429
    @cw74299 ай бұрын

    Great Video!

  • @genevryfreeland2054
    @genevryfreeland20549 ай бұрын

    Great job teach!!!

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Thank you! 😃

  • @patrickkillilea5225
    @patrickkillilea52259 ай бұрын

    Awesome! Melted rock is the best. I was out exploring an area with similar geology... Pumice like stuff. All folded up, lots of Migmatite. No Obsidian though.

  • @rosemaryalexeev5319
    @rosemaryalexeev53199 ай бұрын

    This is so, so cool - to see the obsidian and pumice together in this formation! Thank you for this information and video. Now I'm going to watch your other videos...

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Awesome. Welcome aboard and enjoy the other videos.

  • @cwj9202
    @cwj92029 ай бұрын

    Driving along CA Hwy 139 east of Glass Mountain during the winter, many motorists refer to Glass Mtn. as the "Modoc glacier", because all the snow on the thick obsidian mass resembles a glacier.

  • @carolcamp4828
    @carolcamp48289 ай бұрын

    Such a cool vid👍🏼

  • @jayski9410
    @jayski94108 ай бұрын

    I found the sounds of your footsteps hauntingly familiar. I used to live near an old slate quarry in upstate New York and whenever I used to explore there, my footsteps sounded like yours. Very different rocks, I know but the sound is the same. However when it comes to your obsidian and pumice, I wish I could see the grain structure under a microscope. I'll bet some dramatic differences show up at that level just like in metallurgy. You can tell a lot about the quality of steel and the sharpness of edges under magnification.

  • @CANNABISfreedomNOtaxes
    @CANNABISfreedomNOtaxes8 ай бұрын

    Fun fact: if youre driving into Glass Mountain from Medicine Lake and stop at the little parking area, there is a tree with a giant burl on it there. Back in 1997 I tied that tree in a knot on a Shasta College geology field trip.

  • @Gizathecat2
    @Gizathecat29 ай бұрын

    Beautiful way the lava flowe and folded on itself! I’ve been to Newberry in Oregon and the San Francisco Volcanic region in Arizona. Now I want to see the folded pumice and obsidian flows in California! Volcanic landscapes are beautiful! Thank you for the tour!

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    You're very welcome.

  • @gerrycoleman7290
    @gerrycoleman72909 ай бұрын

    You are not too far from some incredible supervolcano caldera features.

  • @astromanian_UK
    @astromanian_UK9 ай бұрын

    Shawn, what an amazing trek... Your video quality is super. I wish we had such a range of volcanic deposits here in the UK. I'm so envious!

  • @hotrodmoma1
    @hotrodmoma19 ай бұрын

    When I was growing up my Dad told a story of a Mountain in California where you could pick lava rock of the side of the mountain. He brought back a good piece of the black lava rock. When he passed on I got it. It is flat on one side and kind of wavy on the other side and black and shinny.

  • @toughenupfluffy7294
    @toughenupfluffy72949 ай бұрын

    The geologic formation of Big Rock Candy Mountain near Sevier would make a fascinating video.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Yes indeed. I'll add that to the list.

  • @markwalker3499
    @markwalker34999 ай бұрын

    I am from northern California and when I was about 14 (1972)we were over at Lassen deer hunting and stopped at Glass Mountain. Back then there was no restriction on picking up a hunk or two of the obsidian. But, the last time I was there in 2010 there was not a whole lot of the glass left and warning signs to leave it alone. It is still an impressive deposit but nothing like it used to be.

  • @tgchism
    @tgchism9 ай бұрын

    Thanks for the video! Really fascinating the geology involved in a lava flow. I've heard of glass mountain but have never made the drive up that way to see it for myself. I may have to venture up that way!

  • @celticmugwump
    @celticmugwump9 ай бұрын

    Thanks

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Thank you for your kind support. Very much appreciated.

  • @davidemmons7154
    @davidemmons71549 ай бұрын

    Tucker Hill is a rhyolite flow dome in Oregon north of Lakeview. The outer shell is perlite then obsidian and then glassy rhyolite. There was an open pit perlite in early 2000s.

  • @lauram9478
    @lauram94789 ай бұрын

  • @chucklearnslithics3751
    @chucklearnslithics37519 ай бұрын

    Boggles the mind. So the lava must have been "dry" to form obsidian, if I recall previous lessons correctly. Is it correct to assume the pumice gas is from materials in the granite, or whatever the source rock is made of, and not water? And how can the banding happen in the same material? Are the obsidian layers "fizzing" away their gas before they roll along?

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Gases in pumice are mainly those trapped in magma/lava. As lava rolls over ground, water vapor can be added from soil or surface water. Gases move through lava although the viscous nature of these flows, inhibit much movement. Layers are mainly from gas-rich (pumice) vs gas-poor (obsidian) segregation as gases coalesce prior to (and a bit after) eruption.

  • @pierreproudhon9008
    @pierreproudhon90088 ай бұрын

    Over here we had a fieldtrip to a little cone in the Mojave desert, there's a ton of cyan colored obsidian (though my classmates think they're more like grey),I did not believe those were obsidian at first!Looks like they can be several different colors.

  • @daphnewilson7966
    @daphnewilson79669 ай бұрын

    Back in the day when nobody thought grabbing a souvenir was a problem, my family took a big chunk away from Glass Mountain. I still regret leaving it behind in my parents' yard: wonder if new owners have a clue....

  • @johnnash5118
    @johnnash51189 ай бұрын

    There’s more to creating obsidian than just rapid cooling of lava; if it were just the cooling process, the whole oceanic floor would be glass. Obsidian is produced from felsic lava (not produced on oceanic floors) rich in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. It is commonly found within the margins of rhyolitic lava flows; these flows have a high content of silica, granting them a high viscosity (low fluidity.) The high viscosity inhibits diffusion of atoms through the lava, which inhibits the first step (nucleation) in the formation of mineral crystals. Together with rapid cooling, this results in a natural glass forming from felsic lava. This is how obsidian is formed.

  • @annettefilt
    @annettefilt9 ай бұрын

    thanks for a great lecture :) Living in Denmark we dont have volcanoes or mountins, so find it very interesting and realy love geology :)))))

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Glad you enjoyed it!

  • @johndefalque5061
    @johndefalque50613 ай бұрын

    Ajusco in Mexico City, is very volcanic. Vallee de Tezontle-one cliff is red and the other is black pumice.

  • @bettyhouk8727
    @bettyhouk87279 ай бұрын

    A few years ago my husband our daughter an I went up to “GLASS MOUNTAIN “ there are/were chunks of OBSIDIAN AS BIG AS A SMALL HOUSE AND BIGGER GLOBS OF GLASS ! It was amazing! Not just a small amount either ! Very interesting and is a mountain of BLACK GLASS !

  • @jamessmelcer616

    @jamessmelcer616

    9 ай бұрын

    From certain angles and distances the flow sparkles in the sun like a flow of diamonds .I grew up in Modoc county seen it thousands of times and I still think it’s one of the coolest things I’ve ever seen.👍😁

  • @JanetClancey
    @JanetClancey3 ай бұрын

    We have nothing like that here in uk it’s amazing!!!

  • @georgesheffield1580
    @georgesheffield15803 ай бұрын

    There are big boulders and outcrops of obsidian in the Jemez caldera . House size boulders .

  • @maurasmith-mitsky762
    @maurasmith-mitsky7627 ай бұрын

    Toothpaste analogy is useful. Thanks.

  • @shawnwillsey

    @shawnwillsey

    7 ай бұрын

    Glad it was helpful!

  • @toad139
    @toad1399 ай бұрын

    We have a cabin at medicine lake and have seen glass mountain many times

  • @frankowsianik168
    @frankowsianik1689 ай бұрын

    This mountain is upscale and shows a lot of glass! 😉

  • @jamesbond007ca4
    @jamesbond007ca49 ай бұрын

    I know EXACTLY where that is. I've been there before & the last time I was there they were mining it!

  • @aubreyleonae4108
    @aubreyleonae41089 ай бұрын

    At the entrance of the current pumice mine there used to be a small cabin where an old man lived in summer as he cut pumice bricks, sold for restaurants use on grills. Incidentally there was a brothel in Tionesta. My dad had to turn his head when they were driving by in his dads Model A Ford.. His dad was a pentacostal preacher from Westfir, OR. I can only imagine that scenario. Lol Nothing remains today of the milltown but Tionesta still has a store as far as I know, with many pictures of that day.

  • @Eyebagdude

    @Eyebagdude

    9 ай бұрын

    My dad was born in West fir

  • @auflubenn
    @auflubenn9 ай бұрын

    I spent some time at MLV looking at geothermal power development (couldn't get a permit). Check out the ice caves, extensional fissures, and phreatic craters in the area. So cool!

  • @mt.sylvania9218
    @mt.sylvania92189 ай бұрын

    Great video and great area, thanks! Medicine Lake and Newbrrry are so different being shield volcanoes, unlike the Cascade stratovolcanoes. Have you read Vic Camps paper “The Case for a Long-Lived and Robust Yellowstone Hotspot” that says seismic tomography shows ‘fingers’ of magma 75km deep reach out from YHS to Newberry and Medicine lake?

  • @baumgartnerwm
    @baumgartnerwm9 ай бұрын

    I've camped there before. Wearing gloves and old shoes is a good idea if you are hiking around in those lava flows. In some places there are larger blocks of obsidian. There is dispersed camping just south of Lava Beds and reserved camping at Medicine lake. A great place to visit, but remote.

  • @outdoorfrenzy
    @outdoorfrenzy9 ай бұрын

    Has anyone been able to get into the pumice and see what kinds of gasses are trapped in there? The folds were absolutely stunning. I loved collecting obsidian as a kid.

  • @shawnwillsey

    @shawnwillsey

    9 ай бұрын

    Gases are released as the lava rises to surface so no gas trapped in the rocks at the surface (maybe at depth).

  • @outdoorfrenzy

    @outdoorfrenzy

    9 ай бұрын

    @@shawnwillsey I would have never guessed that. Thank you for the little lesson. Now I wish I’d taken more than one semester of geology in college.

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