Buttress unconformity in Ogden Canyon, Utah: two rock units separated by 1.8 billion years of time!
ฝัง
- เผยแพร่เมื่อ 7 ก.พ. 2025
- Join geology professor Shawn Willsey in Ogden Canyon, Utah as he investigates an interesting type of unconformity called a buttress unconformity where sediments are deposited against a topographic feature. In this case, 1.8 billion year old metamorphic rock is juxtaposed against ~20,000 year old gravel from when the Ogden River fed directly into Lake Bonneville, prior to the Bonneville Flood and during the Pleistocene ice age. This unconformity or contact between these two adjacent rock units represents more time than the Great Unconformity, which is also exposed in the canyon and elsewhere in the Wasatch Mountains.
I love doing these videos and will continue to do so but if you want to provide support or much appreciated gas money, you can send support via Venmo @Shawn-Willsey (be sure to put two L's in last name)
or PayPal: www.paypal.com...
or a good ol' fashioned check to this address:
Shawn Willsey
College of Southern Idaho
315 Falls Avenue
Twin Falls, ID 83303
A trip to Ogden canyon is in order. Remarkable how the light goes on when you point things out. The juxtaposition of an ancient era with evidence of the Lake Bonneville crest is special because the lake and flood events are recent enough to see and walk easily observable surface geology. That brought this video home for me. Thanks again.
I'm always amazed at how clear the geologic formations become as soon as you describe them. You do a great job of explaining everything so that even a total novice can understand. The material in the buttress formation is such a conglomerate that it doesn't seem like it should be very stable, but it is very interesting to look at.
I am a retiree who has spent time reading geology textbooks and watching videos, but it's so much better to see the various formations up close and hear the explanations at the same time. You cover just about the right amount in each video so I can comprehend and retain what I'm learning. Thank you!
You bet. Thanks for the kind words and watching. Look for more soon. Subscribe and share with others.
Which has been proven over and over that it's thousands of years and not millions! You types will do anything to disprove god with zero evidence
@@omar-uu8qo Funny sarcasm. Way to skewer those Creationists
Thank You. My Family is from Provo and Ogden. I have been there when I was a little Girl. Very interesting. Love learning about Our Planet. I Love rocks and geology.
Super interesting historial. The diagram was helpful in that it I was able to picture very clearly how the deposition came to be. Thanks Shawn.
Wow, i didn't know that. I like the way you teach. You leave us wanting more. You also have a way of explaining what's happening through time.
Thanks. It's been so fun to do this as a side project and connect with interested and interesting people.
Really clear explanation. Love these films. 👍
Thanks for watching and learning.
Fascinating geological story. I didn't know about buttress unconformities, so that was so interesting.
Yes, these are a lesser known and discussed type of unconformity.
I haven't seen my birth home in many years. Miss fishing that river with my father.
Very interesting and informative video. I like diagram on paper. You do need huge animation to explain complex concepts. Keep posting such informative videos Shawn 👍🏻
Thanks. Keep watching and share with others who might be interested.
Shoot, I’m your number one fan (self appointed) from Australia Shawn, keep em coming mate.
Australia - now, that would be a great place to have Shawn explain its myriad of geological features!
There's actually a guy doing similar videos about Australia's geology...I learned about him when he commented here one time. His channel is called Out There Learning, you might want to check him out.
@@garyb6219 I like how both of them are down-to-earth guys just happy to share their knowledge...very cool.
Thanks Craig. Consider the Aussie top spot yours. I appreciate you watching these. Would love to visit down under sometime soon. My wife and I have tentative plans to come in a few years during the summer (your winter) so it might just happen!
I use to work for Rocky Mtn Research station there in Odgen during the winter months. Sure wish I had known all this information back then, Thanks Shawn. Very interesting.
Better late than never, right? Glad you enjoyed this.
Great geology explanations, can’t wait for your next videos.
Look for 1-2 per week for the next few weeks.
I love these videos. Little nuggets of geology !
The Weber River was the border of my family ranch where I grew up.
I always like when get the notification from your channel, btw the concept is simple enough, short but cover all point
Love the videos!!
Always learning something new from these videos. Geology is so fascinating.
Had no idea such unique rock combinations existed within easy driving distance from where I grew up!
Ogden Canyon is a geologic mecca. I have several videos from there so be sure to check them out.
Great video as always.
North Ogden resident. You should do a segment on the North Ogden slide to the North of the divide road. Learning tons from your videos!
First time viewer and now a subscriber......excellent description and easy to understand explanation....well done!!
Great news! Welcome aboard and thanks for your kind words. Enjoy the existing videos and look for new ones soon.
I really enjoy your videos and always learn something.
Awesome. Thanks for watching and subscribing. The Earth is a good teacher for all of us.
Excellent work!
Great video! You do a wonderful job explaining & pointing things out. So appreciated!
Thanks so much!
Way cool. You can see basalt buttresses in the Tieton River valleys from lava flows from the Goat Rocks.
So amazing! It's it safe to assume the cobble and conglomerate deposits in the Echo canyon to Croydon areas are also all from the Pleistocene? I've also wondered about the rippled sediment rock layers exposed at the Croydon exit off I84, those look much older than Bonneville era deposits.
Echo Canyon area conglomerate is Cretaceous (about 100 million years old). The ripple marks in the sedimentary rocks in Morgan Canyon around Croydon and Devils Slide are Jurassic and Triassic rocks. I'll be doing a few videos there soon. If you know a good location to access ripple marks or other cool stuff, let me know.
07:35 "the weeds" - um, we call that _life_ . Now those could be invasive species but I suspect most of the plant life around there is native.
Other than that, a very informative video. It's very instructive to see different size clasts and that larger rocks are clearly not river cobbles but rock fall from nearby cliffs.
All that smooth river rock in the conglomerate shows there were lots of river systems and of course a whole heck of a lot of water flowed across the land for a many years during and after the Younger/Dryus event 12k yrs ago
I didn't know that a hard conglomerate could form in such a short period of time.
Depends on cementing material (and other factors). In this case, calcium carbonate, likely derived from limestone units in canyon, forms the main cementing agent that binds particles together. Overall, not enough cementation to seriously consider climbing on, but plenty to form cliffs in canyon.
Sir, 1.8 bln years old rock is a basement for younger rocks, so what is a basement for 1.8 bln years old rock?
In general, these high grade metamorphic and igneous rocks that are 1.8+ billion years old and underlie younger sedimentary and volcanic rocks are considered basement rocks. The basement rocks extend down considerably and grade into rocks of the lower crust. You can get older basement rocks by heading east toward the core or craton of ancient North America. As you head west, the oldest rocks tend to be much younger since that land was accreted or added to the continent much more recently.
Those rocks over the road look dangerous. How often do they get rock falls?
Good question. Not much rock fall at this small outcrop across road, but much more rock fall at the large outcrop I visit in second half of video and also another one near waterfall at mouth of canyon on south side of road.
In my area a lot of rock fall is caused by freeze thaw activity. Does Ogden experience these conditions?
Are you or have you done a video on Adams Canyon?
No, but I could. It's right by some family member's homes. What are you most interested in there?
❤
Ahhh. The Paleopoterozoic and a great unconformity
👍