Glacial polish on Yosemite Valley Big Walls?

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Klimmer

Mountain climber
Topic Author's Original Post - Apr 9, 2016 - 07:00am PT
There is plenty of evidence of glacial polish all throughout the High Sierra back country, but is there patches of glacial polish anywhere in Yosemite Valley proper? Is there any on Yosemite Valley Big Walls?

Do any of you know and then where?

Now I known of course the Valley was a U shaped glacial carved valley before sediment filled in the bottom of the valley. Just wondering if the glacial polish still exists in the valley somewhere?

Any one know? Thanks.
Flip Flop

climber
Earth Planet, Universe
Apr 9, 2016 - 07:46am PT
Glacial Polish is caused by the plasma blasts of Starfighters during the last local battle in the Space War between the Lizzies and the Greys.
FRUMY

Trad climber
Bishop,CA
Apr 9, 2016 - 07:55am PT
REALLY
Why don't you go and look for yourself
overwatch

climber
Arizona
Apr 9, 2016 - 07:58am PT
Big surprise, Klimmer is being Klimmered (where everything you write is attacked and belittled)
life is a bivouac

Trad climber
Bishop
Apr 9, 2016 - 08:37am PT
Hey, a little known fact... Back when John Muir drove sheep from the Bay area to the foot hills; and subsequently into the Yosemite, those jump bugs would flock from side to side along the Valley's walls eating sweet grasses.
With every passing summer more and more lanolin laden sheepies polished those walls to near mirror like finishes. And there you have it! :)
Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 08:41am PT
Serious question. It's an Earth Science question. C'mon people. Focus. Get out of your ADHD induced hyper focus on making fun of people all the time.

I'm hoping some ST big wall gurus know and would be willing to share the info for the sake of pure science.

There is plenty of the valley being filled with sediment evidence. There are some small terminal moraine evidence in the valley, but is there any remaining patches or areas of glacial polish remaining on any big walls in Yosemite Valley proper?

I would ask John Muir but he's sadly no longer with us. And I'm pretty sure he didn't get onto the vertical big walls above the valley. But he would indeed be a great resource since this was one of his primary scientific studies beating out the geologists. Great story by the way.
WBraun

climber
Apr 9, 2016 - 08:45am PT
Look around and see .....

http://www.xrez.com/yose_proj/yose_deepzoom/new/XRez%20Xtreme%20Pano/index.html
overwatch

climber
Arizona
Apr 9, 2016 - 08:50am PT
What an incredible tool and I don't mean you, sir, thanks for the link
FRUMY

Trad climber
Bishop,CA
Apr 9, 2016 - 08:52am PT
I not making fun of anyone!

Go look for yourself - that's how science is done.

Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 08:55am PT
WB,

Have you bumped into any in all your Valley big wall climbing and rescues?

I'll have to load the software to use the high definition imagery.

Personal experience is gonna trump remote sensing in this regard. I think you could look at patches of glacial polish in Toulomne Meadows in HD imagery and wouldn't be able to tell.
10b4me

Mountain climber
Retired
Apr 9, 2016 - 09:15am PT
https://en.m.wikipedia.org/wiki/Glacial_polish

And since the mass of a glacier tends to be more in the center, as opposed to the periphery...
Also figure in normal exfoliation.
darkmagus

Mountain climber
San Diego, CA
Apr 9, 2016 - 09:21am PT
Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 09:25am PT
This good general article indicates there might be some near Nevada Falls ...

http://www.indiana.edu/~sierra/papers/2012/klapperich.html


"Glacial polish, another visible marker seen on many rock features in Yosemite allows for a better understanding of which glacial period polished a specific areas as well as their possible age. "The deep weathering of the glacier polish found on the steeper slopes of the Nevada Fall area and on the low ridge that extends east from Liberty Gap into Little Yosemite Valley indicates that it is pre–Tioga in age" (Schaffer, 1977). If the Tioga age glacier had made it this far to the polish, the present day polish would have been obliterated or at least smoothed down much more so than is seen today."
gstock

climber
Yosemite Valley
Apr 9, 2016 - 09:39am PT
The most recent glaciation in Yosemite Valley (the Last Glacial Maximum, locally called the "Tioga" glaciation, circa 18,000 years ago) terminated near Bridalveil Fall. In eastern Yosemite Valley the glacier was just below the rim, but it tapered to the terminus such that most of the walls in western Yosemite Valley were only slightly glaciated. Thus there is much more polish on the walls in the eastern portion of the Valley.

Large areas of glacial polish are visible on the walls of Tenaya Canyon around Mirror Lake, on the Glacier Point Apron, and on Middle Brother east of The Folly. There are smaller, easily accessible areas of polish at Church Bowl (Energizer), west side of Swan Slab, top of Manure Pile, and a tiny patch at the base of Pine Line.
Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 09:43am PT
My best guess, hypothesis, is there must be some residual glacial polish on the massive vertical walls of Yosemite Valley somewhere.

Would be neat to find it, image it, map it, GIS it, and share it. Would be a really cool geology-glaciology study, and a great excuse to go climbing.

I suppose it could be expanded to the entire Yosemite National Park proper not just the Valley. Obviously there is great glacial polish in the High Sierra of course.
Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 09:46am PT
Gstock, very cool. Thank you. Where is your resource, personal experience, published study? I see you're in Yosemite Valley. Thank you.
Ed Hartouni

Trad climber
Livermore, CA
Apr 9, 2016 - 09:48am PT
gstock is The Valley Geologist...
he is the co-author of

Geology Underfoot in Yosemite National Park
Klimmer

Mountain climber
Topic Author's Reply - Apr 9, 2016 - 09:52am PT
Ed, thanks.

Gstock, thank you. Very cool.


Edit:

SuperTopo, what an awesome resource of really knowledgeable people that show up from time to time :)

Shalom



I'm definately gonna buy the book ... Thanks for the tip Ed.

http://www.amazon.com/gp/aw/d/0878425683/ref=mp_s_a_1_1?qid=1460221146&sr=8-1&pi=SY200_QL40&keywords=Geology+Underfoot+in+Yosemite+National+Park&dpPl=1&dpID=51UVqOH%2BIYL&ref=plSrch#immersive-view_1460221212034
Spider Savage

Mountain climber
The shaggy fringe of Los Angeles
Apr 9, 2016 - 10:21am PT
Left side of Swan Slab. there is a wide ledge with a couple of short routes going up it. Go round to the top of this ledge and witness beautiful glacial polish on bedrock.

It is my belief that this is the spot where John Muir proved poor old Josiah Whitney was wrong about Valley origins.

It's quite clear.

I've seen other bits here and they're but not this good.

It is a significant site.
scooter

climber
fist clamp
Apr 9, 2016 - 10:38am PT
If you go back near mirror lake on the North side, walk up to the Valley wall. You will find really nice glacial polish there.
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