Echo Canyon, Utah: impressive cliffs of river gravel shed off big mountains in the Cretaceous Period
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- เผยแพร่เมื่อ 10 ก.ย. 2024
- The towering, scenic cliffs of Echo Canyon along I-80 between Park City, UT and Evanston, WY record a fascinating geologic history of towering mountains and fast-flowing rivers. Join geology professor Shawn Willsey as he investigates the Sevier Orogeny, a major mountain building event in western North America during the Cretaceous Period, about 80 million years ago. Learn how these highlands (now eroded) formed and how the high energy streams that drained the mountains shed large loads of sediment eastward.
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
cool. thanks
So good. Really interesting story and drawing. Great images, very good camera you've got.
Thanks.
Too, for dropping the question inflection
after declarative sentencing
Shawn! Were you a marathoner back in the day? You really put in the miles! Thanks for all you do I really enjoy these videos they really expand my geologic knowledge
Ha, good one. I do not enjoy running and only run when chased! As a college professor, I have summers off and our family travels a lot so its easy to add some geology to our exploits. Look for lots more through the summer and even in the fall. Thanks for watching and learning with me.
To the contrary your drawings are very good. A clear depiction of what you describe.
Outstanding, next best thing to being there.
I love a good conglomerate.. so many types in one space
Being from Evanston and driving through that canyon many times, it was interesting to see those conglomerates but also what appeared to be oil seeping from the cliff. Cool video, great to feed my fascination with geology especially around my old stomping grounds!
Thanks Shawn!
Thanks again for your expert explanation of the features in my neck of the woods. You have made my road trips much more entertaining now that I know a little about how this stuff was produced.
other fantastic episode! I love those conglomerates representing ancient streams eroding out of old mountains. your tectonic diagrams are very helpful in putting the outcrop into a larger historical context. Give yourself some art props too, you're a better artist than you give yourself credit for! I'm surprised those climbing anchors hold on that crumbly rock. Nice to see you out there with a fam! Anytime I can get my daughter off technology is a win, lol, ... as I watch your TH-cam video. ❤️
Thanks so much. She loves climbing now as a young adult.
Thanks, the anchor at about 6:32 looks pretty sketchy, especially given the 'shedding off' of the exposed conglomerate rocks.
The bolt and chain you saw is just a ground anchor for belayers. The trail sluffs off here and its just a bit of security.
@@shawnwillsey Sorry, I was referring to an anchor mid slope, above the chain for the belayers. It looks like it is the eroded gravel layer. Oh, love your videos, I learn so much from them.
@@jimjr4432 The single bolt above me (belay area) is the first bolt of the climb for those leading the climb. Given the compacted nature of the rock and the prevalence of quartzite cobbles (quartzite is very hard and resistant), these anchors and bolts would be more than enough to hold body weight or even a climber falling a few feet to tens of feet. Like all climbing hardware, they should be inspected and retorqued periodically.
That’s where I grew up. Spent lots of days looking for the lost bank loot. Robbers held up a Park City bank back around 1900, fled towards Wyoming. When the posse grabbed ‘em near Evanston and strung ‘em up there was no loot. It’s somewhere in that canyon. Cool rocks too.
It's pretty amazing to see, that conglomerate, really looks like the bank of a river or stream that you'd see on a float or fishing trip now. It looks like it would be brittle or crumbly, but if it's holding those sport bolts, it's gotta be holding together well. You are really cranking these videos out. I look forward to the next notification. Great stuff man. And your drawing was just fine 😊
The sketches are my favorite
Conglomerate can be very hard. This conglomerate looks like it would be a pain to climb with how crumbly some parts appear to be.
It was actually very solid. Not quite as compacted as Maple Canyon in central UT.
Hey Shawn, thanks for this great video. My partner and I put up all those routes. Having spent too many hours staring and swearing at those cobbles it was great to see how it all came to be. Check out our new route on Monument Rock, one of the towers to the west. I'd love to understand how those formations survived!
Hey! So Cool. Well done and thank you. I know how much work it is having put up 50+ routes in the Snake River canyon locally. Bolting in and amongst the cobbles would definitely be more challenging so kudos to you and your partner. I'll look for the new route on Monument Rock on Mountain Project. Thanks!
Only been there once. I did Geo video too. Alas. I am a Precambrian guy.
Thank you for sharing these landscapes. They are amazing to see from my more urban reality.
I'm a biologist and musician, not a geologist, and certainly not a cliff climber, but I once wrote a song titled "Geology" that morphs homo sapiens into its ultimate origins, the Earth. I imagined myself as mountain slowly eroding into, eventually, the sea. The first verse goes:
Raised as a mountain tethered to the sky, the only creatures here are the ones that can fly.
Baked by the sun and soaked by the rains, the rock of my soul slowly comes undone.
Water and rock, two powerful forces that have conspired with all of the elements to create life on this beautiful and rare planet.
I guess I should have searched your videos before I asked you about Echo Canyon a while back. Thanks Shawn! I need to get up there and try that climb, how was it?
The rock took some getting used to (mainly mentally) but is super fun to climb.
So they're overlapping alluvial fans?
I don't think so. Alluvial fans would be composed of more angular particles. These are more likely energetic rivers and streams but maybe they were alluvial fans.
Did my usual thing again to try to locate on Google Maps where you were standing (at 41.0004892,-111.392246 where it says Bear Hollow). And when you switch into street view on the Echo Canyon Road you can not only see the conglomerate very clearly. There are also some layers of shale (only my uneducated guess from the looks of it), maybe 1 meter thick and tilted at around 20° towards NW underneath that sandstone conglomerate which disappear under the surface when you move towards Echo City.
You gotta love Google Maps. Makes it even more interesting to follow your videos.
Good stuff. My location for this was actually about 80 ft or so above the road at the base of the climbing wall. Yes, there are some sandstone interbeds amongst all the conglomerate that form more layered deposits. Glad you could track me down.
👍
Fascinating stuff. I always have additional questions when I learn something. One is, are the mountains there still rising or shrinking? Also what would water levels be there in the late Cretacious? at about sea level we have today? Its inland now but back then it was a sea coast, or near right?
The Wasatch Mountains to the east are definitely still rising. Each quake along the Wasatch fault pushes the mountains up and the Salt Lake valley down. Here, near Echo Canyon, I am not sure these mountains and highlands are rising still (no active faults in region for most part).
Sea level in Cretaceous was much higher than today, about 250-300 feet higher, so much of the continental margin was inundated. A warmer climate with no polar ice caps combined with faster rates of seafloor spreading in ocean basins is the likely cause of the high seas.
Speaking of rock climbing, it would be amazing to see you in Yosemite valley. Perhaps you would stand in wonder of the place. As many of us have.
I like the subject but that highway background noise is terrible!
I love your videos but the only gripe I have on this, with the drawing is that the Western Interior Seaway WAS the hinterland foreland basin of the Sevier Orogeny-the primary reason the seaway existed at this time was due to gravitational loading of the craton interior by those Sevier mountains and imbricated thrust sheets (combined with high sea levels from lack of ice caps during greenhouse climatic conditions and swollen mid ocean ridges during the Cretaceous Normal Superchron, which had the effect of raising global eustatic sea level and filling that downward-warping flexural hinterland foreland basin, whose filling with sediment itself caused further basin development). Based on your drawing though, it seems that the Echo Canyon conglomerate was deposited in another basin, other than the WIS-so were these braided river gravels deposited in some kind of an intermontane basin within the orogen itself?
Hi Avana. Thanks. Hmm. I'll need to look at some refs on this. I thought there was a forebulge east of the foreland basin and then the Western Interior Seaway east of that. If I was wrong, I apologize. The overall story is still fine in that the high Sevier Mountains shed sediment eastward. Thanks for watching and doing some quality control on these. Doing videos on the fly is easy and freeing, but can lead to errors from time to time. I try to keep the facts straight as best I can.
@@shawnwillsey Thanks for your response-So, it is your understanding that this was deposited in the foredeep in front of the Sevier retro-arc forebulge, and that the WIS existed east of the forebulge, in the back-bulge part of the system? That is definitely a possibility I hadn’t considered.
Edit: so, after reading some literature on this topic, it seems that the Echo Canyon Conglomerate (ECC) was deposited simply as synorogenic, proximal sediments shed into the foredeep of the WIS/Sevier foreland basin, and that it grades into more deep basinal facies farther east. The later psephitic cousins of the ECC, the ~65 Ma Hams Fork Conglomerate and ~55 Ma Wasatch Formation were deposited in synorogenic wedge-top (intermontane) basins as the Sevier thrust system gave way to the Laramide system and thrust faulting propagated eastward. The ECC and WIS both were deposited in the main foredeep of the retro-arc foreland system, that is, west of the fore bulge. The forebulge itself was located all the way east at what is today’s Colorado/Nebraska/Kansas border, and sediments that were deposited east of it into the system’s “back-bulge” include such units as the Pierre Shale and the Niobrara Limestone. So the WIS inundated both the foredeep and back-bulge regions of the Cordilleran/Sevier retroarc foreland basin system.
@@AvanaVana You beat me to looking into this. Thanks for the info and clarification. So my diagram was a bit wrong and in hindsight I could have left the forebulge out to simplify and graded the clastic material in the west to a shallow marine environment in the east. Thanks again for your keen and discerning eye. I have another big drawing coming with a Challis Volcanics video I just did. I hope I didn't make any egregious errors there but if I did, you'll let me know. Thanks again!
@@shawnwillsey Sure no problem, but I don’t want you to get the wrong idea with my comment. There’s nothing egregious about it, it just caught my eye and turned out it was an opportunity to brush up on my Cordilleran foreland basin dynamics and facies knowledge. Looking forward to more of your videos. The Challis and Absaroka episodes remain mysterious to me.
@@AvanaVana All good. We both learned, so mission accomplished. I didn't get into the weeds with my upcoming Challis videos but mainly focused on the story of the cool basal (Smiley Creek) conglomerate, the angular unconformity, the tuffs, and the awesome fossilized sequoia stumps. I'll let Nick wade into the tectonics and such on the crazy Eocene.
Dude your finger
It's a climbing finger.