Geology of Mount San Jacinto near Idyllwild, CA

Glad to have you studying with me! I have more content in the works and I hope you'll enjoy it. For those that are interested, the best textbook out there is this one: amzn.to/47VNed8. However, it's a little old now (two of the authors have passed away) and if you prefer a newer textbook, I would recommend this one: amzn.to/45UFDcR
For other introductory geology lectures: • Introduction to Geology
This video describes the rocks and geologic environment that created magnificent Mount San Jacinto in Riverside County, California. This video was filmed on location in July, 2021.
Closed captioned.

[@michaels7566]

Excellent! I am a geologist from the East Coast now retired in an over 55 in Orange County, CA. I used to teach Physical Geology as an adjunct and really enjoy your well constructed video lectures as they are a great refresher for my slowly lithifying stagnant brain. Great job!

[@EarthandSpaceSciencesX]

I’ve taught at several places in Southern California, including Long Beach State, UCLA, and Mt. San Jacinto Community College. I miss being in Southern California terribly! Glad to have you joining us!

[@jdove6883]

Go back into the field sir! I am 62 and have been rockhounding since I was 7 years of age. It keeps you sharp.

[@michaels7566]

@@jdove6883 we moved back to PA recently to be with our first grandchild, and as I write this I literally just got back from Seattle where we had our second. Geology is everywhere so there is more than enough to slow down the lithification process.

[@AintNoFossil]

Would love to see more of this type of content.

[@jimw1615]

I lived in Idyllwild for 17 years, starting in 2001. It is an amazing place for its physical beauty and the wonderful people who live there. Like many small mountain communities, it has become "too well liked" with an overabundance of weekend rental properties and loud brash visitors.

[@EarthandSpaceSciencesX]

I agree with that. The type of community up there has changed quite a bit the last 30 years.

[@visionseeker7678]

I'll definitely be checking out your other videos. I've been searching for this type of content

[@EarthandSpaceSciencesX]

Awesome!

[@lindakautzman7388]

THANK YOU

[@susanharris5926]

Thanks for taking the time out to show and explain about this really interesting corner of the continent. I always look forward to your new uploads.

[@2Phast4Rocket]

Thanks for the video. I used to hike up in this mountain. I am surprised this mountain is still growling at the fast rate as explained in the video

[@ajwiepert19]

I can't thank you enough for all these videos you uploaded on KZbin. Hope all is well.

[@EarthandSpaceSciencesX]

You're very welcome!

[@TheDanEdwards]

Beautiful area. I find large xenoliths in the granodiorite here in San Diego County.

[@MasterMalrubius]

Always happy to see a video from your channel appear in my feed.

[@EarthandSpaceSciencesX]

I appreciate that!

[@angelacret]

Thank you Professor. Nice presentation, maybe you can get the camera closer to the rock so we can get a better look. Some of us live far and away from California. It is quite interesting. Please keep teaching your worldwide audience !

[@EarthandSpaceSciencesX]

Yeah, that’s a good idea. I’m still learning how to do this fully online in a way that works.

[@socalpal8416]

Great video. I had to watch it twice to absorb the information. Especially enjoyed the crystalline break down of a granodiorite and your explanation of Xenoliths. Subscribed.

[@EarthandSpaceSciencesX]

Thanks for you kind comment!

[@jannay4884]

Completed my geo course with a highest grade but still on your channel

[@dardar1862]

Excellent! Thanks! I’ve been to Idyllwild, loved it!! The rocks are definitely very special 💜🙏💚

[@SidWray]

Thanks! I was just in that area last weekend and I highly recommend the Aerial Tram outside of Palm Springs for any fellow geology nerds. It’s a bit expensive, especially if you wanted to take a whole family, but I was blown away by the rocks and views at the top (~8500ft) and the texture and mix of colors of the rocks on the way up was incredible.

[@mattsharpe3989]

Glad to see you back at it Paul!

[@kellypawspa]

Rock on! 💎. 💜

[@johnnynephrite6147]

Cool, i love to hike Mt San Jacinto. Do you think its possible to find hornblend nephrite up there? Also love the Smith River. That was a good video too.

[@noneofyourbusines9976]

Is the mountain still rising? One would think the sheerest escarpment in North America would have quite a fault on its steep side. But in regards to the San Jacinto Mtns all that’s ever mentioned is the strike slip faults in the area. Something caused that mountain to jump up two miles above Palm Springs.

[@EarthandSpaceSciencesX]

Indeed, it is still rising. That uplift is being motivated and controlled by several major faults in the San Andreas system, most notably the San Jacinto fault.

[@conniead5206]

Where was that volcano when it was active. Because it is west of the San Andreas it could have been in or much nearer to Mexico then. I like to know where things were when they formed because I have learned that the geography of the planet was vastly different when major events happened. The hot spot under Yellowstone was in Nevada. The only dinosaur fossil found in Washington was on an island that was part of Mexico when the T-Rex died. They usually use images of how the planet looks now rather than what it looked like during an era. Confusing.

[@doctorofart]

How does a perfectly igneous smooth grain of sand fall off a rock

[@WilhelmvonFahrvergnugen]

I took the rock type for granite...

[@randolphsloan2263]

Can you explain the polonium halos???

[@rogercotman1314]

Thank you for the outstanding Geology lesson.......................... 418 like .........

[@EarthandSpaceSciencesX]

Thank you!

[@secularsunshine9036]

*Let the Sunshine In.*

[@visionseeker7678]

Awesome content. Camping here soon. Hope the mountain doesn't turn into an active volcano! Lol jk cheers

[@EarthandSpaceSciencesX]

I love camping there. Enjoy that experience! Breathtaking views on the hikes.

[@jsmith2132]

Interesting ... Very well done!

[@EarthandSpaceSciencesX]

Thank you! Cheers!

[@jimw1615]

John Muir compared the Idylllwild area to that he experienced in the cental Sierra Nevada mountains.

[@EarthandSpaceSciencesX]

There are some definite similarities.

[@hikerJohn]

Is it the same rock that's on the north side of the 10 freeway around Big Bear and Mt San Gorgonio? I live in Southern Calif and love learning about the Geology and I also hike these mountains as well as the entire Sierra Nevada Range.

[@EarthandSpaceSciencesX]

Yes, these rocks are very similar to those and are formed at about the same time.

[@dillonburns7531]

Is Joshua tree monzonite granite absent of the kphelspar too??

[@EarthandSpaceSciencesX]

It's been almost 20 years since I've seen those rocks at Joshua Tree. Monzonites are usually quartz-poor (less than 5% of the rock) but have abundant plagioclase and potassium feldspar. I definitely recall the abundant feldspar phenocrysts but my memory is that those are plagioclase dominated (sodium-rich variety) with K-spars occurring in the groundmass, but I could be wrong. It's just been so long ago.

[@oscarmolinaoutdooradventur1648]

❤️❤️❤️❤️❤️❤️❤️❤️

[@gabrielcolvin1531]

Thank you for the knowledge! I just hiked up to Mt. San Jacinto's peak last Saturday. These same rocks sit at the very top of the peak! Amazing!

[@butchmilk2972]

You're welcome that was very interesting how big was a rock you look like what I could see is like a 7 ft square I've been higher so what do you need God bless you good video ✝️✡️🌹🐻💖🐼🦩🐦💚💙

[@paulmatherly8934]

Mudfossil University! Behold😮! How long will you stand behind traditions?

[@jeffbrunswick5511]

I love these videos. Thanks so much for making them.

[@EarthandSpaceSciencesX]

Thanks for watching!

[@ricaneva3896]

I live at the foot of it in hemet Its weather changes fast sometimes the clouds get stuck there when it rains

[@aaronosb7787]

What about finding gold on that mountain is it possible

[@EarthandSpaceSciencesX]

It’s possible. Gold has been found in the area but better gold prospects can be found in the Mojave Desert to the east of there.

[@aaronosb7787]

@EarthandSpaceSciencesX sounds groovy

[@patrickkillilea5225]

Granodiorite! We've got it. Great video. I live down the hill in Hemet. This is a very interesting area for sure. I think you start seeing some K Spar over towards Thomas Mt. and down in the canyons by us. But we do not have typical Granite, I guess. So many stratigraphic units around here it is crazy.

[@EarthandSpaceSciencesX]

Next time I am in town I’ll have to look more closely over at Thomas Mountain!

[@randolphsloan2263]

Town you explain the creation of the igneous rocks .. They contain polonium halos !! They did not come from a volcano !!

[@LardGreystoke]

Big Rock Candy Mountain.

[@cpjv1987]

You lost me at 100million. 😂

[@cumhurbabaoglu2585]

I haven't heard of dark plagioclase. They are characteristically white or gray in colour. Secondly, the type of plagioclase in basalts should be anorthite, not albite.

[@EarthandSpaceSciencesX]

I reviewed your comment and think I know why you misunderstood me here. What I said was: “sometimes plagioclase can be pretty dark like what you would see in a basalt, so these (these being those minerals that I’m looking at in the video) are albitic plagioclases.” The word “albite” comes from the latin “albus” which means “white” so I was attempting to compare the dark-colored plagioclase aka anorthitic plagioclase (which is typically gray) with the albitic ones we see in the video. I tend to blend colloquialisms with more formal terminology in order not to lose people who have a beginner level of familiarity with the topic. Hope this explains things.

[@cumhurbabaoglu2585]

@@EarthandSpaceSciencesX Thanks for the clarification. I see that I have completely misunderstood what you refer to in the video because your intonation in the sentence somehow escaped my notice and I thought you referred to feldspar types in basalt by “albitic”. Now everything is crystal clear.